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agkistrodon

Invasives forum?

agkistrodon
10 years ago

Hello. Just wondering if there is a forum on gw that deals w/plant "pests" or invasive plant species. I see there is one for critters but I wish there were somewhere you could go for tips on how to control Japanese stiltgrass, bittersweet, trees of heaven, pauwlonia etc etc. Is there a forum that you can recommend to me for this?

Thank-you!

Comments (24)

  • Lynda Waldrep
    10 years ago

    Here is a good link. This comes in a nice book, free if the publication is still in print, from the US Forest Service. There is also a national list, but this one has more photos to help ID. I noticed that the stilt grass is called Nepalese browntop in this book.

    Hope this helps.

    Here is a link that might be useful: Nonnative Invasive Plants of Southern Forests

  • wisconsitom
    10 years ago

    Adidas, the 'Native Plants' forum deals with such issues. I think you may know that already, but if not, check it out. We do frequently get into such discussions.

    +oM

  • agkistrodon
    Original Author
    10 years ago

    Thank-you both NC and Wiscon!

    The guide to nonnative invasives is a great resource....I'm almost scared to read it as I might find out how many more invasives I have on my little patch :(

    I have on occasion posed questions on both the native and woodlands forums w/regard to invasives but what I'm really looking for is a forum that deals w/techniques that others have used...what works, what doesn't...something I can scroll through...I feel awkward posting many questions about the control of Japanese stiltgrass on a woodland board...the questions I asked on another forum have largely gone unanswered prob because they are "off-topic" for that forum? I don't know. I don't think it's too far fetched to have an invasive plant control forum so I thought there might be something I missed.

    Anyway, thanks your input!

  • Lynda Waldrep
    10 years ago

    Pre-emergents on stilt grass have worked for me, but I hate to use chemicals, and you have to apply every winter for several years. It is an annual grass, as I guess you know.

    Some people recommend burning in the spring after it has emerged. Hand weeding during the summer is the best. Keeping it cut with a weed eater helps, but this plant has hidden seeds lower down, so you only reduce the number of seeds that will scatter to come up next year.

    Since it is a grass, there are chemicals to kill monocots that will not harm most dicots. Oh, the seeds can float on water, and that is why you see so much of this weed around wet areas...and then it spreads. Yuck!

    The link has methods that they use in the forests to control the invasives.

  • agkistrodon
    Original Author
    10 years ago

    Thank-you so much for your help! I stupidly thought that this stuff was hay gone to seed when I saw it. We bought the property 2 yrs ago and I was not sure what the previous owners had done. I cleared, by hand, tons of bittersweet and Wineberry bramble (Rubus phoenicolasius) and disturbed the soil in the process. So, as you can imagine I had a rolling meadow of stiltgrass which the deer rolled around in and any other living thing was crushed under it. I actually found a single putty root orchid...this place was once all forested.

    My plan is to try going a non chemical route...I read that somewhere...I think in PA...but not sure....another technique was used w/success. They left the stiltgrass in place and mulched on top of it. The idea was to cut light to potentially germinating seeds AND apparently stiltgrass doesn't do well when it germinates in rotting substrate. The stiltgrass from the previous yr covered by cardboard and/or leaves woodchips apparently worked well to reduce the stiltgrass coverage....of course I know NOTHING is 100% and for anything to work outside you need to keep at it but I just wanted to know if anyone else had gone this route as it is labor intensive and I just want to make sure my efforts aren't in vain or making the situation worse! Any thoughts?

    Thank-you for reading!

  • wisconsitom
    10 years ago

    Adi, I concur with you-a subforum devoted exclusively to dealing with unwanted, non-native, and/or invasive species would have a place here.

    Another resource worth checking out is your state's DNR or whatever its appelation in your state. Here in WI, they've done a decent job of producing web pages full of just such info.

    +oM

  • kchd
    10 years ago

    We were able to successfully petition GW for a milkweed forum. They agreed after some well thought out points were made. It took a few months to get it launched, but that's ok.

    I suggest you contact gwTamara to make the request and see if you can also garner some support from other GWers.

    Katie

  • Naturedeva
    10 years ago

    There is only one non chemical (somewhat) effective way to deal with stilt grass, and that is to whack it as it begins flowering (but before it forms seeds), which is usually early to mid September. Cutting it any earlier in the growing season will give it an incentive to quickly grow back and go directly to flower and seed.

    In September, start whacking the more mature plants first, which are generally the ones growing in full sun, as these plants will seed up sooner than the plants in less than optimal growing conditions. Cut as low as possible.

    Prepare to do this forever, with increasing levels of success.

    Plant tall and thick-mat native grasses, such as bluestems, in its place in the sunny areas.

  • agkistrodon
    Original Author
    10 years ago

    Thank-you for your input but I *think* the stiltgrass here flowers/goes to seed before Sept. I am away from home much of the summer and return in Sept. By that time the grass has grown, flowered and gone to seed AND has been trampled down by deer. This is my main problem...I'm not here to get it before it goes to seed so that's why I wanted to try being pro active by smothering the bad areas w/dead grass/cardboard and thick mulch. I'd read that this method was somewhat successful but I can't seem to find anyone else to confirm this!

  • K
    10 years ago

    Adidas,

    I just came across this great website today for the Early Detection and Distribution Mapping System (EDDMapS) out of the University of Georgia: http://www.eddmaps.org

    Finally, a way anyone can help! I am giving that link for all the information. What is specific to your question that you can find by clicking on the "species information" tab is here:

    http://www.invasiveplantatlas.org/subject.html?sub=3051

    Fascinating! Apparently this plant may have been introduced because it was used as a packing material for china.

    That page gives a thorough description and more links for management. The couple that I looked at say that for both mechanical and chemical control, you should wait until late in the season when the plants are blooming but not yet seeding. Then mow close to the ground or spray. If you mow too early, they will bloom lower down on the stems, and spraying too soon also "may allow a second cohort of plants to produce seeds"...

    This doesn't solve your problem, though, since you come back after seeds have set. Could you possibly hire a responsible teenager to watch for the flowering and then mow it to the ground for you?

    Kat

    Here is a link that might be useful: EDDMapS

  • K
    10 years ago

    Oh, Naturedeva, I just noticed your reply! Sorry for the repeat!

    Kat

  • agkistrodon
    Original Author
    10 years ago

    Kat,

    Thanks for your help but I live in the middle of nowhere so there really is no one who can help. The other problem w/mowing is that much of the area w/the stiltgrass can't be mown! We live on a sort of rock outcrop and there are rocks sticking out of the ground everywhere...apparently they had to blast the area to lay the foundations and the boulders are just all over! What I have tried to do is leave last yr's stiltgrass in situ and I am slowly covering that thickly with mulch. It takes a long time because I dig up the rocks that I can lift w/a spade, cover the soil w/mulch and relay the stone on top. I guess it can't hurt and maybe I'll get back after the summer this yr and find not a trace of stiltgrass (ha ha ha :)

    P.S. Just goes to show you how invasive this stuff is if it really came from packing material. I mean how many people take packing material out and throw it outside? How did it become SO widespread?!

  • Lynda Waldrep
    10 years ago

    Don't forget that those seeds float, so you cannot even drown them!

    BTW, other invasives have come from packing materials. I think it only takes a few "strands" to float into the air to start these problems.

    I hope this cold winter will reduce some of the invasive plants from the warmer climes.

  • JillyWillyCT
    10 years ago

    @adidas...boy, do I "feel your pain!". We are at war with japanese stilt grass, too! I posted a report from the Fall on GW (http://forums.gardenweb.com/forums/load/woodland/msg081935228788.html?12) Good link from my state coop ext in that string with info on This noxious weed.

    I am girding my loins and getting ready to try the vinegar route this Spring suggested by Esh. This year, I will stay ahead of it...as best I can. It is staggering how quickly this stuff multiplied. I suspect we did everything wrong one year and now will pay for it for years to come.

    Let's report back on our progress. I wish I could have found good info once I figured out what we were dealing with. Maybe we can help others new to this problem!

  • agkistrodon
    Original Author
    10 years ago

    Thank-you NC and Jilly for your input! I don't think the vinegar would work well for me...the problem is so spread out here I would need gallons and I worry about collateral damage.

    I think there has to be an easier way...I mean this isn't bittersweet or grapevine w/roots stretching around the globe and back...it's very shallow rooting and the seeds are tiny. So, though I can't eliminate it completely due to its seeds' "airbourne" nature it seems that one could try to control it by burying the seeds deeply and if soil must be disturbed it could then be quickly covered again w/cardboard, mulch, leaves etc. I've noticed that around here where the spicebushes and pawpaws are growing in groups or patches the leaves from the previous Fall seem to have done a good job of slowing the stiltgrass' progression!

    I find it difficult to try many of the methods that others have tried because of the landscape here. Could you describe the landscapes that you are dealing with? Is the stiltgrass covering landscaped areas? Woodland? Do you leave autumn leaves in place? Do you mulch?

    I even tried collecting leaves from another invasive, Paulownia tomentosa, and covering the stiltgrass with it to smother it....these leaves mat together well!

    Please report back on your progress! I'll probably resort to vinegar/cornmeal or something worse if I don't see an improvement this year...just hoping to avoid it...hope springs eternal :)

  • K
    10 years ago

    Adidas, what state are you in? If you could contain it, I would be tempted to try the burning as ncrescue mentioned. My dad used to do that every couple of years to keep stickers (sandspurs) out of our yard when I was a kid (near the beach). It worked well.

    I would support any effort to get a forum on invasives.

    Kat

  • agkistrodon
    Original Author
    10 years ago

    Kat,

    I'm up near the Appalachian trail in Northern VA....close to Mt. Weather. I don't think I'd feel comfortable burning...it's usually quite windy up here and I couldn't contain it! But boy, I'd LOVE to burn the Trees of Heaven, bittersweet. stiltgrass....this place has got to be the poster child for invasives....anything you can think of...it ended up here!

  • K
    10 years ago

    Adidas, it sounds like you are doing the best you can with the mulching/smothering. I'll be interested to hear how it looks next spring.

    I'm wondering how long the seeds remain viable if they are under the mulch. I suppose you'll have to be careful to just make slits if you plant any new plants in order not to stir up the dormant seeds.

  • Naturedeva
    9 years ago

    Right now at the end of April in northern Bucks County, PA, I see thousands of tiny stiltgrass seedlings poking through the tree leave litter. These seedlings have just two small round leaves when they first sprout, unlike their mature lance-like leaves. They already used a lot of energy trying to poke through the litter and have long, thin fragile stems.

    What I'm trying this spring is to rake over these seedlings, breaking their stems, and then raking the tree leave litter back over any ones that maybe didn't get broken adequately..
    I know I'm risking exposing other seeds by raking, but I think I'm killing a large percentage of viable seedlings with this method. I'll be monitoring and will report back.

    The heavy snow and ice of the long winter has flattened the tree leave litter into a solid flat mat in some areas and I think that this might be a natural defense as I don't see the seedlings being able to poke through (yet) where the tree leaf mat is thick with big leaves like oak leaves. I'm leaving these areas alone.

  • K
    9 years ago

    I recently checked out a book from the library called "A Management Guide for Invasive Plants in Southern Forests" by Miller, Manning and Enloe.

    This book adds to the information everyone has contributed. Apparently, "hidden seeds within leaf sheaves are produced in early summer." Also, prescribed burning can promote spread of existing infestations.

    Minimize disturbance within miles to prevent spread.

    They give a few chemical treatments, but they also recommend hand pulling (repeated) to maintain control and not damage large amounts of other plants.

    Seeds remain viable in the soil up to 3 years.

  • offplumb
    9 years ago

    I am late coming to this party, but thought I would share this link - it's a good one

    "Illustrated, easy-to-read fact sheets on invasive alien plants with native ranges, plant descriptions, ecological threats, U.S. distributions & habitats, background of introductions, plant reproduction & dispersal, management approaches, alternative native plants, and other useful information."

    Here is a link that might be useful: pca - least wanted alien invaders

  • agkistrodon
    Original Author
    9 years ago

    Naturedeva,

    You and I are using similar methods (by the way we lived in Bucks County before we moved to northern VA :) but this is really the first season I've tried anything so I don't have too much to go on. What I did was to apply a layer of cardboard and/or leaves from the invasive pawlonia and then applied a VERY thick layer of shredded mulch on top. The area is quite large so this was extremely labor intensive as my husband is not big on helping outdoors! The areas where I used cardboard I see no stiltgrass but where I was a bit thin on mulch the seedlings are visible and I'm pulling those. I left the miles and miles of stiltgrass that grew last summer in situ because removing it just caused more seed spreading. I have the feeling that the stiltgrass presence will be strong again this year but maybe after a couple of yrs of "cardboarding" and mulching the stiltgrass will lessen its hold. The good thing about mulching and cardboard is that the cohosh (blue and black), violets and bloodroot that live in this area have had no trouble at all breaking through the cardboard and mulch....I worried about using chemicals for the collateral damage it might have caused.

  • agkistrodon
    Original Author
    9 years ago

    Kat: I wonder how you can minimize disturbance for miles? I'm going to have to tell my deer herds to take a different route from now on :)! Funny, well actually not funny...when you're the one spending hrs weeding... but I find even hand pulling disturbs carefully piled mulch and even natives, like meadow rue or cohosh, poking up out of the cardboard and mulch create great spaces of exposed dirt and BANG the stiltgrass pops right up!

  • agkistrodon
    Original Author
    9 years ago

    Bubble: Thank-you for the link! I have a thistle problem too and I find it is interesting that both thistle and stiltgrass potentially change the chemistry of the soil and affect other plants growing near them. I haven't actually noticed this with stiltgrass but the stiltgrass definitely gets tall and dense enough to block light to other plants around them including tree and shrub seedlings. I also noted in the fact sheet that an understory can limit the progress of the stiltgrass and I agree w/this...I have a very nice understory of spicebush ( Lindera benzoin) and the stiltgrass doesn't seem to have moved into areas where the spicebushes are closely spaced. I am going to add some Calycathus and viburnums to this understory in the hope that it might discourage the stiltgrass (a little!)