Arum italicum - how to eradicate

shelley_r(7b NC)

I've just learned how invasive this plant can be. I'm trying to help someone get rid of the arum that has spread over 5+ acres of a beautiful woodland garden. The garden is mostly native plants so we really want to get rid of this pest. I've been told that all the experts say you just can't eradicate arum and my short research backs that up. Isn't there anything that works? Please help me with this. Thanks for any suggestions and information.

Shelley

Piedmont NC

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dbarron(z7_Arkansas)

If you're really determined, perhaps the easiest would be a winter (like now) application of roundup to the clumps. You're less likely to hit much else (that's not evergreen) this time of year...and the arum is in full evidence.
It won't be easy..but you said you really wanted to get rid of it.
Alternatively (silly idea maybe), find nurseries in your area that would like to sell arum italicum and invite them in to dig ?
I live out west and don't believe italicum is a rampaging threat here (w/o irrigation). But having seen 5 acres of vinca minor (back farther east), I believe you...

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gord_pa(z4pa)

Sorry I can't help, but from what I read it is tough one.

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fairy_toadmother

i have dug up my plnt corms many times. apparantly a little bud must survive each time because i keep getting sprouts. i had read not to keep the plants in a wet location. well, it was pretty wet, and the corms were pretty mushy, but they keep coming.

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Tomato_Worm59(OK)

Shelley, you are going to have to get a bigger gun. There should be farmers in your area who use some really potent herbicides. Too many weeds are already resistent to Roundup [glyphosate]. You can get other translocating herbicides, but many may be also restricted-use and will take either a professional or a farmer [with an applicators permit] to help your friend with the Arum problem.

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JAYK(8b)

There have only been a few cases of weeds that have become resistant to Roundup, and these are generally in agricultural situations. There is no evidence that such genetic resistance development has taken place in the scenario described in this thread. If there is a lack of efficacy from Roundup on A. italicum, it stems from the natural and inherent ability of this plant to resist its effects. Glyphosate should work, although repeat applications are likely needed, and it should be timed for later in the growing season. 2,4-d products are also reported as effective on this weed.

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nlin0273(z9-10 CA)

Or give some to ppl who want them. My area is dry so they don't go too far.

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shelley_r(7b NC)

Well, I've done some research and that with the comments here leads me to believe that you cannot dig it out successfully. As fairy_toadmother says, you'll always miss a little corm. As for stronger poisons than Roundup, that's out, too. This is an important wildflower garden and I can't take any chances that might accidentally destroy another desirable plant.

I'd appreciate any comments on the best method of applying Roundup. Just spraying it on the leaves doesn't seem to work. We cut the foliage off some of the plants and dipped the cut stems in full-strength Roundup. Haven't had a chance to evaluate that method yet, but I'm inclined to continue with it. Should I get the plants as soon as they emerge or wait until they've got some growth first. Cut them off close to the ground or leave the stem as long as possible. Or just nick the leaves so the Roundup can enter the plant better. Ideas?

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JAYK(8b)

Roundup is a systemic herbicide and should be applied when the plant is moving energy reserves from leaves to the roots. This varies with the plant, but in the case of Arum it appears to be mid growing season and beyond. Once applied to the leaves and stems, do not cut any foliage. Another addition would be to use an extra surfactant in the spray mix to assure good penetration of the herbicide.

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ahughes798(z5 IL)

Put some dish soap and fertiliser into your Round-up. The dish soap is a surfactant, which helps the round up get to the leaves themselves, and the fertiliser will cause the plant to suck up the round up. Do this while the plant is moving energy and food from the leaves to the roots....usually mid-season. April

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fredsbog

I am a CPA (certified pesticide applicator)(possibly certifiable too :~) I have found the best way to use roundup in a situation like this is to wait until the plants are ready to go dormant and are pulling all the nutrients from the leaves back to the corms. then cut the foliage off near the ground and immediately paint on the straight roundup. it is pulled back to the root system killing the plant. This method has worked wonderfully for me in controlling poison ivy, buckthorn, and several other tough to control weeds.

On another note, I'd be happy to pay shipping for a load of corms, A. italicum is rather rare here and deer (piranha deer that is) won't eat it, and it is not a problem plant in this area. Send me an e-mail if you'd care to share.
Fred

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fairy_toadmother

fredsbog- hmmm, how about a reminder in the spring?

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Rosa(4ish CO Rockie)

fredsbog says....'then cut the foliage off near the ground and immediately paint on the straight roundup'

Thats a great technique for woodies like buckthorn or poison ivy and is a method that is labeled and widely accepted. But for non woody plants, cutting right before application does not increase but reduces it no matter what state the plant is in, and is not recommended. Read the label-it specifically states to apply on actively growing plants. It's also a waste of money to not get max application and max translocation.
I am also a certified applicator....

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shelley_r(7b NC)

Rosa, could you explain why cutting the plant near the ground works for woodies, but not for perennials? I'm not doubting you at all nor the Roundup instructions. I'm just curious and trying to learn why plants behave as they do.

Cutting the Arum near the ground and painting with full-strength Roundup is what I'd planned to do. It seems like the open stems would just suck it up.

Thanks in advance for enlightening me.

Shelley

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JAYK(8b)

There are non-woody target plants for cut application that are known to work well. Knotweed is a good example of this.

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Rosa(4ish CO Rockie)

Shelly

It has to do with the arangement of vascular bundles and the tensions they maintain to move water/nutrients, and sugars in the plant.
In grasses and broadleaf forbs these 2 types of vessels are bundled together and move water/nutrients up to the leaves as the other vessels are moving sugars down to the roots. Cutting the leaves at the ground disrupts the flow both ways. Nothing going up also means nothing going down. This is true for Roundup type herbicides known as growth regulators that are moved thru the plants with the sugars and into the roots and storage organs.

In woody vegetation the bundles are seperate and spaced further apart. The ones that transport sugars are on the outside all the way around near the bark. The ones that transport water/nutrients are in the wood, sapwood and heartwood. They work a little more indpendently so to speak. It's why you can tap sugar maples and not disrupt the flow upward or downward. The pressure gradients for upward and downward movement are slightly different
Cutting woody vegetation at the base and applying herbicide still results in the herbicide being sucked into the roots.

While there are some exceptions to this as KAYK mentions I would not recommend that for you or your situation. Companies spend alot of money and time figuring out exactly what works. It's not a guess, its based in science. I would apply as indicated on the label.

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JAYK(8b)

To clarify some things:
Roundup is not a growth regulator type herbicide. It works by affecting amino acid synthesis.
There is no water transport in heartwood.

There are labeled uses for Roundup application to non-woody cut stems, for example, knotweed, as I previously mentioned.

Another well known examples is Arundo donax-
TNC website:"Arundo- Cut-stem treatment requires more time and manpower than foliar spraying and requires careful timing. Cut stems must be treated with concentrated herbicide within one to two minutes in order to ensure tissue uptake."

All this being said, for Arum italicum a late season foliar application of Roundup at the label rates, with enough surfactant to ensure foliar penetration would likely be a good method if glyphosate is the choice.

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Rosa(4ish CO Rockie)

Yes, my mistake, should have said wood and sapwood. Even tho the heartwood is the central core of the xylem it has lost the abliity for transpost due to clogging of the vesels.

And yes Roundup is indeed an amino acid distruptor-sorry, looking at the wrong column.

But, my labels of Roundup do not indicate any instructions for cutting of herbaceous plants before application.

Roundup Pro & Pro Concentrate, Pro Dry...apply to actively growing weeds..allow growth to reccur before treatment
Roudnup WeatherMax...do not treat until weeds have resumed active growth and reached recommended stages
Roundup Original, Original 11, Original Max...reduced control may result when weeds have ben mowed, grazed or cut and have not been allowed to regrow
Roundup UltraDry, Ultra Max, Ultra Max 11...if weeds have been mowed or tilled do not treat until weeds have resumed active growth

What am I missing here??
I'm certainly not debating whether TNC (a great resource btw) has used Roundup in the manner you stated for Arundo. Just whether the product is specifically labeled for such type treatment and can find none! I can't even find any mention of controlling Knotweed on any label..

For novice users, I always recommned following the label first before getting experimental. In most cases this works perfectly well.

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JAYK(8b)

You will find Arundo cut stem treatments detailed in the Roundup Pro label, for one.

Aside from the Arum question, it is important to know that not all weed targets need to be listed on a label to be legal targets for a given herbicide. What matters is that the *site* is legal for an application. No herbicide label lists every weed that it is legal to be applied to.

I concur that novice users, and experienced users for that matter, should adhere to the label directions.

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shelley_r(7b NC)

I really appreciate all the discussion on the application of Roundup. I have learned a lot. I just want to focus back on one thing, though, which is that the anecodotal evidence is that Roundup applied according to the label directions just does not work with Arum. So, wanting to stick with Roundup rather than use anything stronger, what would be my best bet as to application method? Maybe I can report next year on what seemed to work the best.

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Rosa(4ish CO Rockie)

True JAYK, is the site that's important.
Just trying to find something indicating treatment type for either knotweed or Arundo as mentioned. Maybe just blind in the am without much coffee, lol!!

Shelly, take JAYK's advice, a late season foliar application of Roundup at the label rates, with enough surfactant to ensure foliar penetration...

Many failures in weed control imho, stem from: using the wrong product, a premixed product on hard to eradicated weeds (these are just not mixed in strong enought concentrations to do the job on really tough weeds), and improper application whether that be the wrong time of year, wrong biological stage of the plant, wrong temperature for maximum efficacy, etc...
There are instructions on the Roundup label for mixing at various strenghts. Stick to the label and don't EXCEED the highest rate listed, and do not forget the surfactant at the rate recommended. It's good use of you money to use it-they are not all that expensive in the scheme of things.

Do hope all this helps!!

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madamekikia2z(z6b/nc)

Shelly, I'd like to have some of your Arum Italicum. Are you interested to do trading next Spring? If so, e-mail me. Kiki

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fairy_toadmother

fredsbog or anybody---still want those arums? this years removal is getting ready to begin!

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fredsbog

Yes, indeed I do! Send me a private email with your address and I'll send you some money for postage, unless there are trades you're interested in.

Fred

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raygrogan(Iowa and Hawaii)

Shelley

I may be a year late and data short, but here is what we do in Hawaii to kill bananas. To kill diseased ones (from a virus, BBTD) we use straight Roundup and INJECT it into the fleshy banana plants. Mongo syringes can be had from surfboard shops ("resin syringes" which are plastic and safe to carry casually), wallpapering shops ("paste syringes") or horse feed stores (they have lots of sizes). The metal ones are extremely sharp. I dull mine a little with a file.

A week later you can see the huge banana plant fading fast, and it kills all the attached (and assumed infected) siblings.

Thanks for all the good posts - I was looking for whether the Roundup flowed in the center or bark area of woody plants.

Ray

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rookie_gardener79

I have heard people talk about Arum Italicum as being horribly invasive. Someone gave me some as a gift...Should I plant it in my yard or not, I can't decide! It would be in pretty moist soil, and in partial shade.

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fairy_toadmother

well, after digging, i am still trying to rid mine. miss one little tiny piece of corm and you have anothr plant. i am going to need a bobcat and a large dirt sifter just for a 5x10 area!

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shelley_r(7b NC)

Rookie, Arum would thrive in the conditions you describe. I would NOT plant it.

We used a method very similar to what Fred described. We cut the foliage and carefully dipped the stem in full-strength Round-up. Several people thought that the garden had less Arum this year, so I believe that the method worked.

This will be a multi-year project and I might try Ray's suggestion (injecting Round-up) next time.

Shelley

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greenjewels(Z8/9 MsGulfCoast)

I am so glad I found this discussion! I was just looking at a full page picture of this plant and thinking how great it would be to own one. I wonder why the plant magazines always tell us all the good things about a plant but not always all the bad.

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fairy_toadmother

oh! here's one. mine would flower, but never form berries or the marbled/spotty foliage like the catalogs show- only veined

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sam_md

Park Svce link below errs on the side of caution. Wonder why noone from N.Carolina has reported A. italicum as invasive?
Sam

Here is a link that might be useful: Arum italicum invasive distribution

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amcald

I don't recommend planting this species. It has invaded both mine and my neighbors' yards and is so difficult to get rid of. I have taken to digging them up whenever I see them. So if anybody really wants them I have thousands. But get them quick, b/c I'm going to try the injecting-round-up idea.

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ncrescue

This plant is on NC's watch list A. It is not higher up because the invasive list is based on what has escaped to the forests and natural areas. So far it is only a problem in gardens, really a thug here. I got my first piece from the very garden Shelly is trying to help clean up and am trying to kill mine. Just a few years ago we did not realize how invasive it could be! It is a beautiful plant. Too bad it has such bad habits. Keep working hard, Shelley, and I will join you on one of the Friday workdays! Oh, and remember that RoundUp has gotten some bad press at Cullowhee.

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susanlynne48(OKC7a)

Well, here I am sitting in a garden that has just a few of them, and LOVING IT! I have clay soil, dry shade, and lots of tree roots, so maybe that's why they don't get out of bounds for me. I wish they would spread more, but they seem to stay in small clumps.

Most of you must have nice fluffy soil yours are growing in, so that they spread like mad.

BTW - this is not native to North America; it is an exotic species from Southern and Western Europe that has naturalized in gardens here in the U.S.

Susan

If you like them, try growing them in pots, a buried pot, or buried tub of sorts so the tubers don't multiply outside of a confined environment.

I think they're beautiful, and here they are green all winter in my drab, brown landscape.

Susan

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genie_wilde

I have an idea.

These just started springing up in my vegetable patch, and while they're beautiful, I'd rather they stayed away from my tomatoes and basil.
So I'm going to try bringing them in as houseplants. If they survive, that's cool. But given my track record with houseplants, they haven't got much chance! *G*

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genie_wilde

On a serious note, Susan, you may have just helped me solve my dilemma.

First, I have trouble growing anything (but blackberries and wild morning glories and English ivy) on the north side of my house, because it's too shaded, the soil tends to get dry because of the roof overhang, and because the soil is mostly clay. Maybe I can transplant my (volunteer) Gigaro to that side of the house and let it do its thing there.

But I love your idea of putting them in big pots, where you can enjoy their beauty but keep them from strangling the veggies and flowers.

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silent1pa

My bulldog thought that one of my two clumps of arrum italicums was a great place to pee. Now I only have one. Maybe a short term ph adjustment to the locality of these clumps might yeild some effect?

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ahughes798(z5 IL)

Don't plant the stuff, don't give it away. It is causing serious problems in natural areas in some parts of the country. All the advice given on eradicating this weed with Round-Up is good, and should work for you. This is a tough plant to get rid of, good luck!

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joepyeweed(5b IL)

I am concerned that there is a discussion about eradicating an invasive plant and yet people are asking for divisions of it.

DON'T PLANT IT! DON'T TRADE IT! DON'T GROW IT!

The plant may not be listed as invasive where you live right now, it could become listed as more information is collected over time... save yourself the hassle and keep invasive plants out of your landscape, no matter where you live.

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silent1pa

Hmmm I don't know. I myself and sad to see one of my clumps go. Especially since I have had these two clumps for twenty+ years and have enjoyed the "hassle". So if you have no intention of maintaining your gardens properly then by no means should you bother with invasives. If however you actually like to work in your gardens then arrum italicums are really not that hard to control. I'm sorry all but I feel specimen cultivation to be just as important as maintaining natives.

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joepyeweed(5b IL)

Specimen cultivation is NOT the same thing as invasive species cultivation.

There is plenty of a. italicum growing in its native Europe. And this forum is geared toward planting natives, which invariably leads to a discussion about controlling invasives, not propogating them.

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rcrrachel

This plant is the worst ever. DO NOT PLANT IT!!!!!!!!
I have dug it, injected purple round up into the ground, sprayed it with round up, covered it with black plastic for the entire summer and now...... it is growing through the plastic and spreading into my beds.
I asked at Portland Nursery what I could do- and the horticulturalist said VOODOO.
Funny- but true?
I might just have to move to get away from it.
I have worked so hard on my garden and this plant is invading all of my hard work.
What else can I do?
What other chemicals or techniques can I use?
Please help!

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ddelisle_dolphinmsds_com

Hi rcrrachel,

I am in the same boat as you. I bought a house in Woodburn 2 years ago that has most of the backyard covered by Arum Italicum. My thought at the time is that I love to work outside, and I can deal with the stuff. Eesh! what a job!

Last year I sprayed D4 Amine on the Arum and it did kill the foliage, but it returned this year. I have been getting outside nearly every weekend and digging up the corms this year.

I really wish there was an easy way to get rid of this pest. If you find one, please let know:)

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pandora(Z5 OH)

!!! I cannot believe my eyes. I bought some plants from a very very well know nursery in 2003.
The clump has hardly expanded. I even collected the seeds
and planted them at the base of the clump a couple years ago.

How can the nurseries sell it? I really like it. Now I have something to worry about.

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ncrescue

I don't know how, but I wanted to share that recently on a tour of a public garden that is supposed to be "natural," I saw this plant everywhere! Someone must have donated it years ago, and it has spread far and wide to all corners of this park. The green leaves are lovely, yes, but they will never be able to subdue it, must less control it. Does anyone know if it stops other things from growing up through it? I do know that English ivy, as horrible as it is, does allow some things to grow up through it. I don't want ivy, but at least it does not smother everything...just kills trees and pulls the mortar out of the brick walls. That's not a nice plant, either.

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phutchin_mt

When we moved to this house in 1991, there was a little of this stuff. The berries made my daughter's hands itch which first got my attention. I didn't know what it was then. It has since invaded every bed. Here in Portland, the leaves come out in winter, flowers about July followed by the berry stalks in September. I have tried a lot of sprays and stuff. Diluted round up will kill the leaves if saturated, but still it flowers and proliferates. I have never tried using straight round up concentrate. My neighbor has suggested crossbow(?). Awhile back on this site someone from Hawaii suggested injection of round up. Did that work for anyone?
Since it is in theory actively growing now in midwinter, I am going to try cutting the leaves and dipping the stems in concentrate for a few minutes. It was a little hard to follow the earlier discussion by certified pesticide appliers, but I think that was the recommendation. I also thought about applying PREEN around the base of some of it. I think that is a corn based product that inhibits growth.
May as well experiment this year. I'm done trying to dig it out.

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raisa

Here is a little organic trick I use with hard to get rid of flora - - 'boiling hot water'. Just hard boil (not simmer) some water and carefully pour it on the plant you want to get rid of. It works wonders on weeds and grasses that can come up between the cracks of your drive or walkway as well. I know that what you want to do is kill it ..and this trick may not do that..but it will keep it away for a long time. To try to kill it ..add a good bit of regular table salt to the water then bring it to a boil. Most plants hate salt and will die.

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greenhaven(SW MI z6)

Gosh, I am glad I found this before I panted three new arum italicum plants in my garden! I hope someone sees this.....

I am choosing to destroy the plants I have while they are still potted. They are not foliating right now, what is the best way to destroy the corms?

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ahughes798(z5 IL)

Bake 'em in their pots(or not) in a 200 degree oven for an hour..then throw them in the garbage.

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greenhaven(SW MI z6)

Thankis, ahughes! I will do that unless I find out that boiling will do the same thing! ;o) Will it? A lot less energy to boil than bake. Except...I DO have a little toaster oven! Nevermind...I'll you the little oven!

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ontheteam(5a-6 (S.Eastern, MA))

could you nuke em in the microwave? the potted ones? As for the fields they are trying to clear.. good luck!

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eagerdrone(Zone 8)

Wow, this thread is almost 4 years old. I wonder how the original poster has faired on her war against Arum.

I dug up about a 2x8 patch this spring. pulled out numerous sprouted bulbs/corms and many unsprouted. Will repeat as needed next year, year after...

I'm also battling morning glory from the North n'bor, Cherry, English Ivy, Himilayan blackberry from the South n'bor, and forget-me-not (beautiful but they're everywhere), Holly from the West n'bor.

Enjoy!

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greenhaven(SW MI z6)

ontheteam, I nuked my arum a few days ago. Worked very, very well...until they caught fire! :/ Arum is dead for good, but my microwave will forever smell like burnt arum, I'm afraid.

eagerdrone, I battle morning glories, too. My back neighbor used to hang fishing line and let them climb into my pine tree. This was every year (3) the house sat empty. Now they are everywhere and I can hardly get rid of them all.

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ross_j

Arum Lily is a problem for us here in Northland New Zealand.
As a Biosecurity Officer, working for the Regional Council, I often get asked about such plants. We have found Grazon (picloram and 2,4-D)seems to work, or Metsulfuron methyl, although it takes longer.
I'm running some trials thisseason, so should be able to come back with some good information!
By the way, I've never had any lasting result from glyphosate on any of the arum family, no matter how it has been applied
The Aussies have been fighting it's spread for many yeasrs as well.

Here is a link that might be useful: Western Australia Arum Control

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bkwandel_charter_net

This is a great discussion, and the info on how glyphosate (I likely mangled that spelling) works is so valuable I'm going to print it and file it. Thanks to all.
Just for clarification, in which zone does arum italicum start to be a pest? I'm in zone 6, and I want to plant it, but I want to be mindful of this plant's invasive potential. FWIW, here's my two cents on the invasive plant debate: If the plant in question is not known to be a pest in your zone, I don't see any reason not to plant it. Ornamental exotics that behave themselves and are avoided by deer and other critters are always welcome in my garden.

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cfsmisc

I have been trying to eradicate arum italicum for a few years now. Sometimes I thought I was being successful, but I think I am losing. I have regularly used Round-Up and have also dug them and used a torch. I have decided to dig them as soon as I see them now. No arum plant has been allowed to go to seed here for over three years. They do appear in new places seemingly by immaculate conception, so more places to attack--to dig, burn, glyphosate--anything. I am relentless, but so is this plague. I would not give arum to my worst enemy, for I consider it a plague to the planet. The only suitable place to plant this beautiful plant is in concrete or stainless steel--and then not allow it to go to seed. It can reproduce easily underground and by seeds spread by birds, I believe. FAIR WARNING! I believe it is a plague in any zone!

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esh_ga

I got the Plant Delights e-newsletter today and I thought it was odd that it said:

At Open House this winter, I had a couple of folks comment about their arums spreading by runners to other areas of their garden. This is an oft perpetuated garden myth, since arums, like me and my bad knees, have no ability to run. When arums are allowed to set seed, birds can pick up the seed and deposit them anywhere throughout your garden. This is the only way arums can spread. If you get to the point where you have enough arums, simply cut off the flowers or developing seed between the time they flower in early May and the time the seed ripens in July.

I think most people on this thread would disagree with that.

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jprich

I purchased my house south of Portland, Ore., almost two years ago now. I have been using Crossbow (active ingredient: triclopyr + 2,4-D ester) for about a year and a half (once in late spring and once in autumn for anything missed in spring). I just got done applying it again and am ready to get a flamethrower. The arum, along with their patches, seem to be getting smaller but it's migrating into my perennials which makes spraying difficult.

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sophy_pearl_gmail_com

Have just found this thread having googled 'how to kill wild arums'. Having looked at the Wikipedia entry I realise, duh! that I also have several very large spadix in the borders which I have been uprooting, but my Dad asked me to leave one because the birds like it. http://en.wikipedia.org/wiki/Arum_maculatum. When the ground isn't frozen, I'm going to fell the last one and not leave any of the berries around, because it could be the birds spreading the arums after eating the berries. I'm going to keep searching for some sort of alternative way of killing them - there must be something wild lilies hate, eg cigarette ash?!

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JustChalk_hotmail_com

Lord, it did my heart good to see so many others out there that absolutely are beside themselves trying to get rid of this obnoxious weed. My mother-in-law gave me this plant 45 years ago. I wish she had taken it to the grave with her. I live in rural Oregon and it is always wet. I the guy that said he needed a bigger blow torch.

I too have a huge yard, but this is war. Since we spray the roads with weed killers I'm going to pinch a few gallons for the yard. These things are under bushes, snuggeled up to the roses and have traveled with the compost to all corners of the yard. It is a nightmare.

And the nurseries continue to sell it.

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mosswitch

Hmm. Arum Italicum "Pictum" has been in my zone 6 garden for over 20 years and has not spread to more than a couple of places other than where it was originally planted. Clumps continue to get bigger but it doesn't seem to be reseeding anywhere, not even close to the original plants. However, I will keep an eye on it for seedlings in the woods in the future. As of now there are only 4 plants, two of which I actually planted.

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tlfp11_aol_com

I live in Zone 6 in the northeastern US. I had a landscaper plant about 20 corms several years ago but never got more than a few speckled leaves every January. I thought I had purchased inferior corms, or the clay here was too heavy & dry, so I planned to purchase more this year. However, this chain of posts has made me reconsider. But I really like them so may roll over and try Susanlynne's suggestion and plant them in pots. I'll keep you posted. BTW, I wonder how the originator of this thread from 2003 made out.

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ncrescue

The garden where the original poster worked is STILL having volunteers dig out these plants! I have to say we have made some progress, but look how many years it has been...and how many volunteers help out there. The soil in the garden is so good and soft that these plants just send down their roots so deeply that it is hard to get them out. We keep trying.

I have some of these arums that I am trying to get rid of. Got them via the original garden but with other plants. They were lurking in the soil that I took home.

And the saga continues.

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Poohshunney_comcast_net

I too have invasive italicum arum and believe me you don't want this stuff, I live in Oregon and bulbs flourish here I also have grape hyacinths that are just about as invasive and these bulb type plants are like the energizer bunny they keep producing and producing. Turn your soil over and you'll see the bulbs all over the place. It is very frustrating. I am going to try the Round up because the stems of the Italicum arum go down a ways in the soil and it is difficult to remove the bulb and if you use a shovel and cut it, you just have two new arums to deal with later. I think I may have contracted this Italicum Arum disease from a local soil company that composts soil from peoples

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fusa

Has anyone tried a flame weeder on their Arum? I just bought a flame weeder, and so far am impressed with how quickly the weeds die. I thoroughly water the area I am working in, to avoid fires, and I keep my hose handy...

Another idea, dig up what you can, cover with several layers of newspaper and then mulch over that.

Just some ideas, I don't own the plant and have never experienced it.

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Katheryn2

Watch out for local soil companies that turn other peoples yard debris into mulch and compost, I think that the bits and pieces of the bulbs left over in their yard debris are what start these invasive plants in our gardens and yards. I didn't have this problem until I bought the local compost for my garden. Also check out the article in this months April/May 2011 edition of Mother Earth news about "Killer Compost".

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dena_eft(7)

Well... this is a scarey post. I traded for this on the Aroid forum some years back,and have just noticed that my "Arums" are getting out of control. Excuse me, I need to go dig. :) Arum

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cfsmisc

Since I last wrote in 2009--before I had arum italicum on the run--I was frustrated. I have found a product that will kill it. It is Speedzone. Google this to find local sources. I have almost no arum emerging from the soil. 3 days ago I saw another leaf emerging, so I sprayed some premixed Speedzone (which I now have on hand always). Today the that leaf is bowing toward the ground and will die. Success again! Nothing I have tried in the past, including digging (which seems to spread these invasive plants), burning, Roundup, etc., has worked. Speedzone does!

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StevenDouglas

Hey thanks for the great tip on the speedzone, I will have to try that out. I have been battling this stuff for at least 2 years in my garden and I just cant seem to get rid of it!

Great Kindle Fire Coupons 2012 Get a great deal on the Kindle Fire. You can get coupons and other great deals at Damngreatdeals.com

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rizzir(z7b TN)

We bought a house last March that is infected with Arum. Since we have a 16-month-old who loves to put things in his mouth, I have decided it must all go - all parts of the plant are poisonous, and the berries are particularly enticing.

I have noticed something about the lifeway of the plant that may be useful to know. It appears that the "mature" plant does not give off many of the pea-sized corms at the plant base, but instead has "nobby knees" that could become new plants - in other words, they are part of the plant base and don't easily split off if you gently remove the adult plant. It is the JUVENILE plants that are actively corming. They are shallow-rooted in comparison to the adult, and growing in a group. If you disturb a group of juveniles, you will see corms of all sizes (some quite small) go rolling everywhere. My strategy is to gently loosen a clump of juveniles and throw out the clump in one piece. Then, hunker down and pick through the loose dirt - you'll get the majority of them. Be aware that not every corm is round. I've noticed that the plants that are so young they are "single-leaf" do not have corms at all, so you can move a bit faster when working them.

I have seen arum corms attempting to grow from over two feet down in the soil. It is incredibly tenacious. While I do not like chemicals, I may start carefully using Speedzone here and there.

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growershower(Z7, MD)

@ JAYK: do you work for Monsanto?

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Jabali

I'm surprised no one has mentioned Casoron in this six-year old thread. This pre-emergent is safe around shrubs (except hydrangea and a few others with green stems to ground level).

If your bed includes perennials or bulbs it unfortunately will kill them as well. It works by killing emerging stems, so will work well with this arum. Apply to dry soils and let rain or light irrigation activate it. Do so just before the arum sprouts in your area. Do not use in very light sandy soils.

Let me emphasize that this chemical should only be used with established woody plants to kill grasses, bulbs and broadleafed weeds. It should not be used in perennial or bulb beds or anywhere these or seeds will be planted for a year or more.

growershower: Speedzone is not made by Monsanto, so what is your point? You could spend a few seconds on a web search rather than showing everyone you are acting on assumptions.

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bioman7

I have what appears to be Arrow Arum, which came up after installing a drip system (it likes wetness). I erradicated it very simply. Using about a 1 1/2 to 2" piece of pipe foam, I then inserted a 1" strip of paper towel, folded and put inside the foam (which can be pulled open). After pricking a few holes with a safety pin or small nail into the plant about 2-3 inches above the ground, I sprayed the towel inside with ortho groundclear, then wrapped the foam around the base of the plant, just above the ground. I fastened it tightly with heavy plant wire. It appeared to kill not only the primary plant, but its offshoots also. I don't know if it works for all Arum species, but give it a try.

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Persephone.3363

Hi, I'm also trying to eradicate this plant for a client who has it coming up everywhere in his quarter acre block. We have found that digging only stimulates the growth.
Have referred it to a local grower, who has advised me to first slash it, then apply double strength Roundup (available from Agricultural suppliers) to new growth and repeat every 9 days. They said it only needs three hours of dry weather to be effective. Hope this works & hope it helps you too!

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jprich

I went out a bought SpeedZone at Coastal. It isn't any more effective than anything else I've tried: crossbow, roundup etc.

AND in the past week I've been to both Al's Garden Center in Sherwood and Dennis' 7 Dees on Powell and both have Arum Italicum for sale. Al's said they would notify the buyer and Dennis' 7 Dees worker said people still buy it (as if that's a legitimate excuse). I proceeded to ask her how to eradicate it and she said you had to make sure you don't ever disturb the soil (till it) and dig it up which begs the question: why are you selling it?

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Jim6810

I think a key to eradicating arum is being methodical and persistent. As bad an invasive as this plant is (I HATE IT) and as indestructible as it appears, I have to remember it's a plant -- and has plant needs. One of its needs is foliage to feed the tubers and roots. Whether you use an herbicide or manually pull or cut the leaves(I find them easier to pull), if you consistently repeat it each time new leaves appear you'll eventually drain the tubers of food and energy.
I first started seeing it in my yard a few years ago and eventually traced it to seed from the neighbor's yard. I applied a broadleaf herbicide during active growth on maybe 3 or 4 occasions -- I was allowed to spray the neighbor's clumps as well. I use a 1-liter hand-held pump sprayer and get down close to the leaves so I can control the spray drift better. A couple times I did also dig them up (I use a good spading fork -- easier than a spade or shovel) and I spent several meditative hours separating bulblets from soil. As thorough as I thought I'd been, there were still some the next year. That's when I decided to just pull up and/or spray the leaves and stalks on a regular basis. That's worked pretty well.
Across the street is a woodland that's also been contaminated with arum -- that's going to be the next project. But for now I pull flower stalks when I see them (they're bright white and are easy to spot), and I check later for seed clusters in case I missed any flowers. I pull the stalks and make sure they go to the landfill and not to the city yard debris compost. I agree with the people who say that's one reason there seems to be more invasives spreading. I'm a landscape gardener, and during the past 15-20 years that city-wide yard debris composting has been going on I've seen a marked increase in invasives and plant pathogens in the landscape. I'm convinced it's from the yard debris that's brought from all over the region, composted (it doesn't get completely composted) and used for mulch. But that's another topic...
Good luck to everyone!

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dbarron(z7_Arkansas)

It is a tough plant...compounded with the problem that Roundup is most effective during periods of fast plant growth, when temps are around 70+ F. Unfortunately, Arum italicum is usually dormant then :)

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LeeLeeMc

Oh my goodness I am so happy to have found this thread! I bought a house in Portland last fall. This winter has revealed that the backyard is literally covered with Arum. I am not exaggerating - the only place the stuff isn't growing is the concrete patio. For the time being I have covered the entire yard with many layers of burlap but I'm ready to try a nuclear strategy.

Does anyone here have suggestions for dealing with a *huge* infested area? Dealing with each plant individually isn't realistic. SOS! And thanks!

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tomrigid

LeeLeeMc, having spent summers ripping away at Willamette Valley Arum infestations, I'd recommend this:

https://www.youtube.com/watch?v=aCbfMkh940Q

I wish I was joking. The idea that anybody in North America could still be growing this stuff, it blows my mind. And how can people still find it attractive? Is poison ivy attractive? Is the soft twilight glow of radioactive waste attractive? We have to let our pain and hate inform our perspective. I hate Arum and it pains me, and my brain now thinks it's hideous. I find this both appropriate and convenient.

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greyim(8-9)

I wonder what outcomes people have had on control of this?
We have been working on a patch (hand dig and hoe) for several years and still they come up :-0
More recent advice has been to treat with eg. Brushoff (metsulphuron) and wetter, 1g to 15 lit. with a weed wiper or paint brush trying to avoid runoff because this may affect 'good' plants

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LeeLeeMc

Update on backyard arum infestation in Portland, OR:

1) Speedzone does, in fact, kill it, but it only really worked for me in the spring while the growth was still "fresh". I only tested this on the leaves so I don't know if it is effective on flower or seed stalks. I haven't gone through a full year yet so waiting til next spring to see if this herbicide reached the corms. It will definitely kill everything else too; smells like toxic petrochemical hell. I recommend a mask and eye protection.

2) For areas you don't want exposed to disgusting chemicals, mechanical suppression seems to be doing the job. As I posted before, I've got everything completely smothered in burlap (near veggie beds). It's working fairly well to control the arum...now we wait each other out. Vigilance!

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twalton

Digging them up only spreads them. We have it in a contained area between the sidewalk and house. Twice I dug out the dirt at least a foot down and replaced it with new dirt, put down cardboard, landscape fabric, newspapers - they still came back. This last time I put down fabric and heavy river rocks. They were gone all summer but started sprouting on the edges this spring. I have sprayed the leaves with this formula in one gallon of water: 1.5 ounce each of Glyphosate (full strength Roundup) and a chickweed/clover killer (Bonide), one scoop of Miracle Grow and some dishwashing soap. Do not do this if it's windy out or the temperature is over 80F (it will kill other plants). I have done this twice in a week and the leaves look like they're chewed on. I may add more soap to make it stick better. Put a bucket with the end cut out over it before spraying if you have plants next to it.

If you have a small clump you can try digging it, but dig way down and the dirt will need to be bagged or thrown on a burning pile. I would mark the area to see if it comes back next year.

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marmarwheweb

Another Portland, Oregon infestation here. I've been lurking in this thread and really appreciate reading other people's stories, especially updates on progress. I, too, asked for advice at Portland Nursery and basically got an eye-roll and "it sucks to be you" from their horticulturalist - this is much more helpful. I've (half) joked with neighbors that we need an Arum Support Group - for now, this is it for me! (along with neighbors).

Our story: We moved into our house in July/August 2013. Knew nothing about arum but a friend spotted it right away and warned us. We collected and threw away the berries but otherwise ignored it, being busy and not realizing just how bad it was until the following spring. Then we dug out a bunch of patches, throwing away the dirt (which filled our trash can and is SO heavy!), and patiently sifting for corms.

This spring, we're trying smothering in some parts, and I've been pulling up the greens. I just can't face digging it up yet, and like Jim6810, I hope it's still a plant, after all! My husband thinks it's better this year where we dug it last year and he promised to find me photos - I'll share if he does.

Right now I'm eying a large patch in a raspberry patch. The raspberries aren't well placed, so it won't be a tragedy if it all has to come out but it's such a large patch it makes me tired just looking at it ... ugh.

I may try Speedzone, especially where it's growing up in the lawn. And I promise to update! I sure do hope Houzz keeps this forum alive.

Stay strong, fellow Arum fighters!

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gracelouise9

I'm yet another arum italicum sufferer in Portland, Oregon. My infestation was slowly spreading & not too extensive until I invited a neighbor whose gardening ambitions outstripped her space to put some vegetable beds in my backyard. She started by rototilling, which transformed a some scattered clumps of AI into a widespread mess with big areas that are very dense (just as it is in her own rototilled back yard.

Do not rototill arum italicum!

We've both dug hard & long to try to make progress against it.

I think I've gained some ground in the areas of lighter infestation -- doing mop up work this year & likely next year also, expecting that if I'm persistent, I'll clear them eventually.

My neighbor worked very hard to try to dig it all out in the heaviest infestation areas last spring, but it looks just as bad this spring. She's is moving away, so I'm taking control of that area again now.


My plan (encouraged by a post above): going to stop letting it photosynthesize by keeping the main areas covered with cardboard & heavy mulch for the next 2-3 years while I work to gradually eliminate it the lighter infestation areas by yearly digging. After that, I'll revisit the worst areas & hope they will be diminished enough that I can dig it out from them too.

(It's odd, but I found I sort of enjoyed going after it this year. Hard work but good exercise. You could get really fit eradicating AI. Each deep cluster of corms seems like a little trophy.)

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ncrescue

Good luck in your project. The original poster was working in a garden in which I sometimes help, and I know that after 15 years we have made progress using multiple methods. Such a pretty plant and such a headache!

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joni2717

I have been battling arum italicum for years and have found that no matter what I do, it comes back stronger. It LOVES chemicals, like roundup and stronger ones, so DON'T use these. Recently I think I have had some success. I have a test patch with a little fence around it, so we shall see what happens over the next few years before we claim success. What I did is cut it level to the ground, and pour white vinegar into each open stem. It was a warm day, and it appeared to shrivel the stems. About a week later there was new growth coming, so I figured it was a failure. The new growth was actually some very sickly looking flowers. I then cut the flowers off and poured some agricultural strength vinegar down those open wounds. This has been about 3 weeks now and it looks gone. There are a few little ones coming up in the patch that I probably missed the first time with the vinegar, so I will get those in the next few days. I will keep you all posted. Meanwhile, please don't use the nasty chemicals. They don't work and it isn't worth it to your health or the environment. I am very sorry I ever even tried them.

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jenz

Do NOT plant this time-consuming invader! I have been dealing with this horrible invasive pest for years and finally feel as though I am winning. Haven't tried the vinegar method but I totally agree with Joni2717's comment about chemicals and herbicides - they don't work on arum italicum. I have a large garden and this invader has penetrated almost every bed BUT after intensive and very patient efforts over the past two years (!) I am seeing real results. My method consists of just digging it out with a garden fork and using my trusty garden sieve into which I put the plant with a large lump of dirt attached. I have now dug out large areas - driving the fork deep into the soil and getting my hand under the master corm with its little bulbs attached. Over the last two years this has massively reduced the number of plants in my garden and I am now in the happy state of being able to go around the garden each day with my arum italicum antennae at full alert and spot each new baby. The baby plants only have a single bulb so once it's out - it's OUT! Anything bigger than a baby is the problem because once they reach adolescence these plants have at least one other bulb attached. By the time they are adult plants they can have any number of bulbs attached to to the original corm and of varying sizes too with little teeny white bulbs underneath the corm and bigger brownish ones all around it. These bulbs pop off really easily hence the fork and the sieve and the determined removal of baby plants now that I've finally managed to remove so many plants and bulbs from my garden!

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marmarwheweb

Every story of success - even partial success - brings great me great joy and strengthens my heart for this battle. Thank you for sharing this!


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marmarwheweb

For Portland, Oregon area sufferers (and others) - I thought the map on this page from the Center for Invasive Species showing arum italicum was interesting and helps me understand why there are several of us commenting on this page from Portland: http://www.invasiveplantatlas.org/subject.html?sub=13931

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tcarasco1

thank you for the map (it's a little frightening). After spraying them this spring I haven't seen them back all summer (I posted above as twalton). We are trying to create a natural area in the back of our yard, but there are a few large clumps growing back there. We will probably use the river rocks again over heavy landscape fabric to create the look of a dry creekbed. Then it's merely a matter of pulling out any that try to peek out of the edges. You have to remain vigilant in the rainy season. The one nice thing about this hot, dry summer is I haven't seen hide nor hair of them. Once the rains begin they'll probably return.

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Michael Sherrell

Botanists -- how long will the bulb survive without a leaf getting sunlight?

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Michael Sherrell

2-4D at double strength, with a couple oz. dish soap/gal, possible multiple applications. Alternately: cover the ground with newspaper for a year or two.

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ncrescue

This post was started in 2004. I volunteer at the site that was the subject for the original post. I hate to tell you all, but after many years of trying ALL of the above things, we still find some of these plants. Thus, in answer to how long, one could say a life time struggle. However, digging them out if you avoid breaking off a piece is about the best of all things we have tried. And yes, we have eliminated most but not all in the two ac. site in over a decade.

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marmarwheweb

Thank you, ncrescue, for that update! It's starting to sprout up all over in our backyard in Portland. Feels so exhausting! One thing we did find interesting was by putting down two layers of landscape fabric and then bark in an infested area that seemed too big to dig, it does at least make it easier to spot the arum as it sprouts since nothing else makes it through, and we've been lopping off the top leaves as they come up. But it sounds like we'll need to commit to a lot more digging. I've been telling my husband we need to treat it like late-stage cancer - we may never cure it but if we can have good quality of life thinking of it as a chronic disease, that may not be too bad.

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brigittegraham48

Hello from UK. I have read all your really helpful comments about eradicating arum italicum. As it seems weed killers are not very successful, would upsetting the Ph of the soil they are growing in might kill it? I am not a horticulturalist, but I understand you can kill off stinging nettles by slightly adjusting the Ph to the alkaline side of neutral.

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ncrescue

This was not tried, Brigitte, as most of the plants in the area need/like acidic soil, so we would not be able to change the Ph as that property leans toward sweet soil as it is. But progress has been made over the decade plus, so there is hope!

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wisconsitom(Zone 4/5)

Such jiggering with soil pH (not PH, not Ph, not ph) is sure to fail. You simply can't make a big enough difference to matter, plus the buffering capacity of many soil types will have it right back to square one before you know it. Nettles controlled in this fashion? Well, I needed a good laugh!

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Michael Sherrell

I believe about 15 years ago I covered an area about 10 yard x 10 yards with newspapers and stopped an outbreak.

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ncrescue

On small areas it probably would help. The original property mentioned in this topic was over two ac. I have used cardboard and newspaper to kill things as well as solarizing via plastic and Mr. Sun.

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Michael Sherrell

We have a gopher infestation around here and I'm thinking they spread the stuff by eating it and not digesting it all. Sigh.

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ncrescue

Never considered gophers as being the source of plant problems. Made me chuckle. Thanks for the amusement!!

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Michael Sherrell

Yeah, well, when you see a line a yard long of little things with a big one at one end, it's suspicious.

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marmarwheweb

For those of you who are like me obsessively googling resources on eradicating arum (it's the season for it here in Portland OR!) - this article from 2014 from the Washington State Noxious Weed Control Board was interesting: http://www.nwcb.wa.gov/pdf/Arum_italicum_draft_written_findings.pdf

I was also interested in what our friend from Australia discussed above. The link wasn't good anymore, but I did find this:

https://www.agric.wa.gov.au/declared-plants/arum-lily-declared-pest

and this - which says it may need updating [ Paraquat?!]

https://www.agric.wa.gov.au/herbicides/arum-lily-control


In our case, we are noting that it's spreading in some areas but the leaves are younger and smaller where we took out the big older clumps. This year we're documenting where it is in our yard more closely and specifically.

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hardwarequeen

Wow, I read up on Paraquat. It actually reduces the corms as well. But it's nasty stuff and may only be applied by licensed applicators. Hmmm, going to look into that.

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hardwarequeen

Hubby and I bought a lovely English Cottage style house set on .4 acres in suburban Portland, OR two years ago. I noticed a few plants and thought they were quirky, like the house. If I could only go back in time. Last year, I dug and torched. This year, they came back with a vengeance, covering half of the backyard, popping up in the lawn and the vegetable garden, and spreading to the neighbor's yard. Hubby has talked with the Integrated Weed Management Coordinator at the Oregon Dept. of Agriculture, Noxious Weed Control. She has a colleague who has had some success with Capstone. However, that's for agricultural use only. Said colleague recommended Bonide Poison Ivy and Brush Killer BK-32. I haven't found it around here, but it is available online. She also recommended SpeedZone. I'm off to Home Depot to get some, and I'm ordering the BK-32. If this doesn't work, we're just gonna have to sell the house.

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Michael Sherrell

Try a 2-4D mix at double strength, with some dish soap to break through the leaf surface; maybe multiple applications. Also, I have experimented with simply plucking the leaves as they sprout -- so far my two experiments have succeeded after 3-4 pluckings.

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marmarwheweb

A neighbor mentioned that he'd heard arum was spread by ants. This is intriguing to me since we haven't let any go to seed for a couple year and yet it spreads to new areas - often in little "paths" (and we don't have gophers). Anyway, I found this article but I'm not science literate enough to understand it all. It looks like the process they discuss applies to the fruit, not the corms.

https://www.researchgate.net/profile/Xim_Cerda/publication/235770680_Dispersal_of_non-myrmecochorous_plants_by_a_%27%27keystone_disperser%27%27_ant_in_a_Mediterranean_habitat_reveals_asymmetric_interdependence/links/09e4151365a7c3e289000000.pdf?inViewer=0&pdfJsDownload=0&origin=publication_detail

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wisconsitom(Zone 4/5)

Marm, I didn't have time to read that link just now, but the absence of seed production in such a plant has very little bearing on its spread. The spread of such plants is due to their rhizomatous root systems. Basically, rhizomes are underground horizontal stems. Plants with rhizomes are capable of colonizing lots of new ground via this structure. Flowering and subsequent seeding have nothing to do with it.

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ncrescue

UPDATE! Just visited the site that started all of these posts, and I am happy to report that most of the BAD plants are gone. However, we still find a few sprigs here and there. Remember, this is now a garden managed by many volunteers, and it has been 12 years since Shelly first posted. So, the answer is many different ways to try to eradicate, but it takes constant efforts and multiple years.

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radiantpoppy(7)

Well... here I sit with four bulbs that I bought for $5. Silly me. I was looking for the proper planting depth but you all have convinced me not to grow them. Thanks for helping me head this plant off at the pass.

I appreciate it :)

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ncrescue

People still plant them, and I guess they might be OK in pots. Of course, I have wasted more $$ than that on plants that I killed by accident, so don't beat yourself up about your purchase.

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marmarwheweb

NCRescue - that is so exciting!!! 12 years is a long time, but it's not forever and we're three years in now. Congrats on your hard work paying off, and thank you for holding up hope for the rest of us.

Wisconsinitom - the significance of the seeds is related to the article you didn't have a chance to look at and what it says about ants as a vector. I'm very familiar with those darned rhizomes! But sometimes they spread in ways that seem impossible without the help of something and ants was one possibility posed, but the article only references them eating the berries. Hope that clarifies a bit!

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wisconsitom(Zone 4/5)

Radiant, roughly speaking, where are you? This makes a difference in how this plant behaves. Here in Wisconsin, for example, it can be grown safely. That is, its spread is controllable.

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dbarron(z7_Arkansas)

I have actually seen much worse spreaders (aka japanese anything (wisteria,honeysuckle, kudzu for example))....here in Arkansas.

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ncrescue

Vines are particularly bad, but invasive properties vary according to geographical sites, and even within those broad areas, there can be differences of wet/dry, acidic/neutral, etc., that will affect just how invasive plants can be. I think this particular species, since it really shows up in the late winter here, gets overlooked in many gardens until it is rampant, thus a big problem.

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tcarasco1

In March I bought some heavy landscape fabric from a greenhouse supply plus some U-shaped metal stakes. Overlapped 2 long stretches of fabric and staked them down well over the infestation area. Covered it in heavy drainage rock (it helps to have teenagers with money incentive for this). It is now September and haven't seen any yet. If any peek out I have some Speedzone on hand which worked in a couple small clumps in another area. Had to buy it online as I couldn't find it locally.




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ncrescue

Good job! And the kitty watcher is great, too.

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tcarasco1

thanks! That area was a mess back there, covered in ivy, blackberries and arum. Had some nephews over for a couple weekends and got it all cleared. The ivy has stayed away mostly, but I think I'll need to spray the blackberry shoots this fall. Digging them up is not working. I have had no arum problems since I covered them, but I will update later on in the spring. I forgot to mention I put Casoron down first before the landscape fabric. Figured it wouldn't hurt, but it's probably not necessary if you're trying to avoid chemicals.

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wisconsitom(Zone 4/5)

Personally, that "landscape fabric" is a mistake. I see the organic mulch material about to be spread over the top of it. That stuff decomposes, dust and soil blows in, weed seeds blow in, and before you know it, you've got weeds anyway, plus an icky unnatural layer between the crucial very top layer where all the organic matter is and all the life, and the deeper soil layers. Air and water movement is disrupted by that stuff. Not recommended by modern landscape protocols, plus, the presence of that impervious layer means none of the good stuff from the decomposition of that mulch is a wasted opportunity.

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louise453

Hi All, I just wanted to report that after years of trying various products and also just digging them up (which never really works as there is just about always a few bulbs left behind, even with sieving) I have had some luck on quite a large test patch in my 1/2 acre garden. I used a simple Round-up wipe-on Gel, available from any hardware store. First I applied it as directed to the top-side of the leaves - after waiting three weeks this seemed to have no impact whatsoever. Next I tried wiping it on the underside of the leaves, they seemed a little yellow and sickly after two weeks, so I repeated the application on a two-metre square section of my initial four-metre square test patch. Interestingly, the areas that weren't treated twice seemed to recover, but ALL the arums in the patch that got wiped twice died! It's been over two months and they haven't returned in that patch, also, as it is a wipe-on gel, the other wanted plants are unaffected. I'm now rolling out a campaign to treat the rest of the section. So, in summary, wipe the underside of the leaves, repeat the treatment after two weeks. Let me know how you get on.

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ncrescue

Congratulations! I never heard of a wipe on gel but will check on it to help get rid of monkey grass/loriope that has invaded everywhere. I dig lots of it, but sometimes there is just too much. Thanks for sharing your "report."

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louise453

This is the stuff I used: https://www.youtube.com/watch?v=P2QKI6bX0nw. However, note it didn't work on the top-side of the leaves (which are quite waxy), and it required a couple of applications - it is easy for a home gardener to use though (as opposed to sprays which require mixing and are hard to target).

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ncrescue

Wow! I will certainly look for it!! Thanks again.

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pontyrogof(8b)

I have successfully eradicated arundo donax, yellow nutsedge, cogon grass, phyllostachys aurea, etc from their toughest footholds on where I do not want them, each over a three year span, about the same amount of time the herbicides take.

But, rather than killing off good organisms, I introduce more by doing one thing: burying the weeds at least a foot deep under slow to degrade trimming chips from utility trucks, and sometimes even deeper with 3 by 3 by 3 foot brush piles. I do this a small section at a time manually to give the microbiomes time to adjust.

After the first year the top layer of the bad roots slide out with a potato fork. The second year the mulch loosens the soil deeper, so the middle layer of bad roots slide out with my potato fork. You can extemporize my third year results.

Maybe this method works for the alum. Pine straw has worked as has gallons of used coffee grounds on various tough rhizome plants for me where I cannot drag chips. Bales of straw plopped unopened on top of the newly cut weed patches can work. Then the straw is already there for future good gardens.

I respect the idea of altering ph in some situations. My goal with mulch is to cause weeds to grow SPINDLY with roots too deep to hang on with, easy to pull. What I do not pull by hand I cultivate with a three pronged rake and mulch some more. My surrounding desired native plants flourish from the improved soil.

I do this in kudzu and air potato land. Once I began to see the benefits of mulch, the possibilities became seemingly endless.

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jfadmz

Here in Dallas, this plant spreads far and wide. Seedlings come up over 100 feet from the closest seed source, so more than just ants must spread it. If I had it to do over again, I would never have planted it. But I did, and it really is pretty. Mine are "Marmoratum." They have variegated foliage in winter and spring, 8-12" white spathes in late spring about the time the leaves begin to die, and Arisaema-like masses of red-orange seeds in summer. I don't like that it comes up all over, and I try to pull the seed clusters while they're still green, although I inevitably miss some. All in all, though, in this climate it doesn't seem to actually crowd out anything else, and it grows happily in deep, dark shade through the dead of winter. I try to uproot any new seedlings, but the variegation doesn't appear until they get to about 4-6" high, so they're easy to miss, and by the time they become conspicuous, pulling or digging them only seems to induce them to multiply. I have other weed problems that are far worse: Asian jasmine, white ash, privets, hackberry, yaupon, pecans, oaks, Bermuda grass, Zoysia grass, blackberries, poison ivy, snailseed, wild grapes, Callery pears, Mexican plums, wild germander to name only some. Again, I wouldn't have planted it if I had known how it spreads, but the genie's already out of the bottle, and I have worse weeds to contend with. Of course I don't live in Portland; it sounds as if it's a plague there.

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Luisa Holder

Hi, I live in Britain, and am trying to find a way to get rid of this myself too.

It seems strange, that although this plant is so invasive, that people continue to suggest sharing it? I'm unclear how it spreads, but last year I only had one or two specimens and this year I have hundreds. I am so sad, as its taken a lot of hard work to get my garden to the point it is now. I feel like its all going to be undone by this poisonous species. I hope you find an answer.

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marmarwheweb

At some point I realized that Jim6810 and I not only live in the same town (Portland), we are old friends! He is the one who first pointed it out to me in the yard of our then-new house. Anyway, his latest theory (and I find it convincing) is that worms are one way it is spreading. This makes sense to me because of the patterns of the paths it makes in the lawn (keep in mind that we haven't let it go to flower and seed for four years now). I didn't have much luck with Speedzone. Digging has had an impact in some areas, including almost completely eradicating in some smaller areas. Our next step is going to be to divide the worst area into four parts and try different approaches in each: heavy mulching and manual removal of what comes up; mulch + spraying what comes up with glyphosate; no mulch and spraying what comes up with glyphosate; cut & paint the ends with glyphosate. The most worrisome trend is the bits spreading through the lawn. This year they are tiny leaves and we're plucking them as they come up. Anyway - that's our spring update!

Edited to add link to article on earthworms as weed spreaders: http://wssa.net/2008/08/underground-gardening-by-earthworms/

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susanfelts39

Here in TN the spread over 57 acres is frightening! After much reading, I have begun what will be a 3-4 year project to eradicate Arum. It is most obvious in winter. I am spraying SpeedZone with a sticker spreader and making sure the undersides get sprayed. Since this is a huge area, it takes weekly walks with a 1 gal sprayer to spray and re-spray patches that have developed over about a ten year period. We have lived here for 30 years. Gardening is my life. I just started this process a month ago and I see progress, but I also see new leaves sprouting from the clumps. It grows from bulbs. Do not dig, the bulbs break off and regrow. It is December now. I expect to patrol and respray through the next two months. After that, my regularly gardening cycle will demand my efforts. If I continue this program starting next November, I expect a real improvement. This plant, though pretty, is a true minis.

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ncrescue

You will have to do it multiple times. This thread started many years ago,and the original garden still has some...but it is finally under control.


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susanfelts39

Yes, This is Not the first time I have sprayed the evil stuff. I cannot believe it is still being sold, and on Amazon no less. I wrote in and told them what I think of it! I am a master gardener and hope to get the word out further. It shows up so much better this time a year.

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ncrescue

I am now volunteering at a different garden from the original poster, and guess what, Italian arum is one of the worst offenders. I feel as if I am starting all over again! There is also lesser Celandine Ficaria verna, which was mistakenly planted as marsh marigold. I cannot tell you which is worse, but getting these two under control will be another decade plus project.

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Fresh air please!

Wow, unbelievable discussion about Arum. This stuff is a bummer but is it possible to lighten up a bit? It’s not evil and it doesn’t belong in your microwave! I’ve got it and it’s annoying, but to me it’s actually satisfying to just dig up. Get your spade and get a workout. Have a water bottle nearby, smoke a little somethin’ and make it disappear for the season. Gotta dig deep but the roots show themselves bright and easy to follow. I fill up wheelbarrows and load them with other yard debris to take to the local forest recycler. Please consider using your physical ability and muscle over Round Up! It’s cheaper, better for you and it doesn’t support a totally lame corporation. Round up is the easy way out and it doesn’t even work for just about everyone here. I won’t buy it.

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jfadmz

I agree with you. I just dug up about a bushel basket of it today, but I don’t hate it. It really is pretty, and it grows in deep, dark shade that not much else will tolerate. The white-variegated leaves really brighten dark areas in December, January, and February. After what I dug up today, I’m going to let the ones I missed alone, let them bloom, and I’ll try removing the red berries later in the year to keep them from propagating further.

I planted mine 20 years ago and they are thriving and providing seed for volunteers at at least 12 neighboring houses—I feel bad for that, but the genie’s out of the bottle now. All in all, it’s very moderately invasive here in Dallas, but it’s not the same sort of menace that Japanese honeysuckle and privets are.

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ejoyce2008

I too live in Portland and just learned about this plant and yes I have a lot of it. I decided to dig deep and sift the soil over two grades of screening. I found lots and lots of corms. Here is my question: If I have sifted out most of the larger corms, will the little ones still sprout or will they just die a natural death because they are no longer being fed by the leafy plant? Any thoughts?

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gardengal48 (PNW Z8/9)

Yes, the little corms will sprout just fine all on their own :-)) This plant IS a listed invasive in many areas of the country and especially here in the PNW. There is a 2 acre patch of it that has colonized Lopez Island in the San Juans!!

Control is difficult. Digging just serves to spread the corms around unless you are extremely thorough in sifting them out. And it is not very receptive to herbicides - the leaves have a very waxy cuticle much like English ivy that resists herbicide penetration. And herbicides seem to have little effect on killing off the corms or tubers anyway. Treated plants will often resprout rather rapidly :-)

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ejoyce2008

Damn those little buggers.


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marmarwheweb
Has anyone tried metsulfuron?
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gardengal48 (PNW Z8/9)

I wouldn't be comfortable using any herbicide that has a nearly 2 year residual effect in the soil.

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Audrey Doggett


I am in the process of carefully digging a bunch of these horrible weeds up - I now call them "devil weeds". I'm digging deeper than I hope the many tubers for each leaf, it seems, live and taking every tuber I can sift out and throwing it in a black trash bag and then into the household garbage. Some of the tubers I've found are as small as the seeds on a blackberry so it takes a lot of time and patience. I'm hoping this is going to work!

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Albert Ross

Thanks to everyone who has posted on this thread over the last 14 (count 'em) years.

We moved into a 4000 sq m garden here in the central west of NSW earlier this year and as I have explored the garden I keep finding clumps of this horrible weed.

So far I have found that AI laughs at Roundup (at least when it is applied to the tops of leaves) and that digging it up and sifting out the tubers and rootlets is quite therapeutic. I am going to try the suggestions here until I find one that works for me and will report back.

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dbarron(z7_Arkansas)

I have a theory, that maybe it's not really Roundup resistant, just that Roundup is most effective when plants are in active growth and Roundup is ineffective when temperatures are cooler.

Since the arum grow in late fall through winter, and add in glossy run off leaves, you have a situation where Roundup doesn't work well. Just an idle thought, in effect yeah Roundup doesn't do the job here ;)

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Albert Ross

I was at a Christmas in July lunch today and one of the guests was keen gardener (age 92). She recommended cutting the leaves off the stems and painting the top of the stumps with mineral turpentine(mineral spirits in North America)which she suggested would kill the bulbs. Any thoughts? Turps is a possibly a bit toxic to other living things, such as frogs which is one reason I am not keen on Roundup etc.


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Probably Not

Has anyone managed complete eradication of a few relatively contained large patches? I have around five clumps in my yard, and after reading this whole thread, I'm irrationally terrified that it's going to take over my entire property/make my future gardening a nightmare...I'm in zone 9b, and have let it hang out in my garden undisturbed for around 3 years. It doesn't seem to have spread far and wide like some others have reported, but it's definitely spreading in the shade of the trees it's under, and I'm extremely nervous that it'll contaminate and colonize my other acre, which is damp and shady. I've dug up a couple patches, and definitely missed some of the corms -- they really do explode when you dig them up! Does anyone have any positivity/advice for me at this stage? ncrescue, did you manage to eliminate the early infestation on your own property? I must admit, I'm panicking a little over here, lol! I can't seem to find any reports in which someone successfully 100% eliminated this plant, and I've looked very hard...it's extremely disheartening! I'm worried that it's going to spread and affect my neighbors, or that if I someday move out, the next person won't be able to keep on top of it. It's just soul-crushing, especially since it only recently appeared in this area. Worse, I have chickens, and they love to scratch at the disturbed soil and presumably throw the corms everywhere...eek!!!

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joni2717

I have sort of given up. It is everywhere. I try to cut it down to the ground at least, and I cut off the red seed pods or whatever they are and throw in garbage to keep birds and squirrels from spreading, but other than that, I almost think leaving it alone is the best thing, as any digging or spraying seems to make it stronger. Once in awhile I'll burn a patch with the weed burner, but nothing makes it go away permanently. Take a deep breath and admit defeat, I think:) Sorry I can't be encouraging!

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Probably Not

Ah, good to know...thank you for your candor, joni2717! I'll adjust my expectations and aim for minimization rather than eradication. I guess that since it appeared it my garden in the first place, it would probably reappear even if I DID eradicate it! It's currently confined to a 5' by 5' region, so I do have some hope that I can reduce/contain it still, especially since I'm on the edge of its preferred climate, zonewise...we'll see! I'm going to dig up all the plants I see and pick out the corms as much as possible, just to see if it weakens the clumps at all, especially since others have reported some success. I'm not sure why I was so disturbed by its presence...I guess it's the fact that it's new, and I don't know the extent to which it might spread, unlike other existing invasive plants on my property. However, it's not like invasive plants on my property are new...I guess that to some extent, invasive plants and weeds are an inevitability in the garden, and I'll just have to add pulling Arum leaves to my list of spring chores. At least this one happens to be pretty! :) I've certainly let it set seed for the last time, lol. I'll check back in months/years to report on my results, and I encourage others to do the same...it's nice to know what you're up against, even if it can be stressful to hear at first! And to everyone else who's struggling with this plant: I know that it can be horribly frustrating not to have complete control over the species in your yard (I could really do without the star yellow thistle, personally!), but I'm sure that your gardens are beautiful anyway. You're all doing great! :)

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