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sweetmagnoliame

Aphids on Plum Tree

sweetmagnoliame
16 years ago

I apologize if this is a duplicate, several times over! Almost overnight I discovered an infestation of aphids on a plum tree. The local garden store recommended a spray formulated for fruit trees as a first step. If that doesn't work, they recommended a systemic insecticide placed at the base of the tree for 12 months of control. The caveat to the systemic recommendation was that the fruit would be poisonous. Adjacent pear and apple trees are not yet affected, but that's apparently likely. I'm reluctant to spray because of vegetables near the trees. Suggestions?

Comments (25)

  • digit
    16 years ago

    A systemic insecticide for a fruit tree? for aphids? Wow!

    Aphids aren't tough, Sweetmagnoliame. Insecticidal soap will kill them. It is my first choice for aphids.

    Insecticidal soap is rather expensive and if you'd like to try a lower cost alternative - I've used 3 tablespoons of Palmolive Green dish soap for every gallon of water as an aphid spray. It worked very well and didn't cause damage to the leaves.

    With either, spray late in the day. You can rinse the tree the following morning with clean water. You should probably spray the other nearby trees.

    Dad's plum tree gets aphids every year. He has used soap spray with a hose end sprayer. The type of sprayer he has was made for trees.

    digitS'

    Here is a link that might be useful: For trees up to 25 ft. tall.

  • bpgreen
    16 years ago

    I'm not sure how well it would work on something like a tree, but soap makes a pretty fair insecticide. There are even some soaps that are sold for that purpose. I think almost any soap will work, though.

    If I remember correctly it works by interfering with their ability to breathe.

    Here is a link that might be useful: Article on insecticidal soap.

  • bpgreen
    16 years ago

    I need to start checking to see if somebody else gave the same advice I'm planning to give before I hit submit.

  • digit
    16 years ago

    Not necessarily, BPGreen - I'm reassured that others may 2nd my comments and so may the original poster. Further, the link you sent offers appropriate cautions - Phytoxicity, for instance. And, "do not use extra strength, grease-cutting, or anti-bacterial soap."

    Also the recipe: "one teaspoon of liquid soap such as mild Dove®, Pure Ivory Soap®, or Dr. Bonners® or pure castille soap, per quart of water." This makes me wonder whether 3 tablespoons is too much. That's just over double what the author is suggesting.

    Here's what Loyola U says about treating spider mites on hibiscus: "Use Palmolive or Dawn or Sunlight soap at one to two tbs. per gallon to smother the insects on the plants. If you need to use more than 2 tbsp/gal, remember to later rinse off the plant. Spray twice a week until bugs are gone." I think Sweetmagnoliame would be well advised to rinse the tree before it is hit with strong sunlight.

    digitS'

  • cnetter
    16 years ago

    In the mean time, you can wash the aphids of with just a strong jet of water. While this won't keep them away forever, but it's a pretty good control. Aphids are fragile and break easily. I learned about this way back in the DRS days and it worked good enough for my roses.

  • david52 Zone 6
    16 years ago

    Do you have the kind that make the leaves curl up? I get those on plum and peach.

    If you can remember, a spray of dormant oil in the early spring before they flower / leaf out will really help with over all numbers.

    I just sprayed mine with insecticidal soap, I mix up a 2 gallons of the stuff and spray all the fruit trees as well as some of the vegetables, the fruit for aphids and the veggies for flea beetles, this time of year.

    I am already seeing 2" grass hoppers. Yikes.

  • lilacs_of_may
    16 years ago

    I have the dreaded black aphids on my cherry tree. I released several hundred lady bugs around the cherry tree, my peach tree, and a couple dozen around my veggie patch last night. Tonight, I saw maybe half a dozen. They had a smorgasbord of aphids! Why did they fly away?

    Let me know how the soap thing works out.

  • Beeone
    16 years ago

    Not to be technical, but I don't think the soap smothers the aphids, it dissolves their "waxy" covering, causing them to dessicate and die. Never used it but I would expect it to work since an aphid is probably a waxy shell holding in 90% water.

    Other things that work well include malathion and many of the other common insecticides for yard & garden, although if you can soap or wash them off, you shouldn't have the impact on the beneficials that insecticides do and a good crop of lady bug larvae will do an amazing job of cleaning up the aphids.

  • digit
    16 years ago

    Yeah, it's those "monstrous" looking larva of the cute little lady bug that stays put, Beeone .

    Tender aphids can bring most any plant to its knees but it doesn't take much to blast aphids to Kingdom Come. (Of course, I'd be in trouble too if someone covered me with shampoo and set me outside, in say 20% humidity, to enjoy 8 or 12 hours of naked exposure.

    Protect your garden.

    digitS'
    Consarn it! I ain't givin' up without a fight!

  • jan_barber61_yahoo_com
    12 years ago

    I have the same problem this year on my plum tree,its loaded with aphids.The leafs are curled up and a mess.The tree is next to some of my veggies to,no fruit on my tree this year came,last year i had so much fruit on it the family really enjoyed them.Help!!

  • david52 Zone 6
    12 years ago

    I have severe aphid problems on both plum and cherry trees as well, and the way it works, the aphids get well established before the predators get going, the end result is stunted growth for the tree that year. Just big, curly, yucky blobs of sap and leaves at each growing tip.

    So I'm working on timing an initial spray to keep the aphids in check until the predators get going. I imagine its temp related, but in practice, its a question of looking at the plants as the leaves come out, then spraying them when you first see aphids.

    You can use soapy water or something like malathion.

  • rosietheriveter_hotmail_com
    12 years ago

    After reading soulutions on this topic, I pondered for a bit...while looking at my power washer...the light bulb went on.... I blasted them off, it did no damage to the tree, or leaves as I put it on a not so harsh spray setting. I'll check in the morning again to see if any more appear.

  • dllfb
    11 years ago

    My aphid problem started on my italian plum tree last summer. I'm so disgusted I'm ready to chop it down. I gave it the dormant oil in late March and since that time
    I have had to spray malathon three times for aphids already, in 3 months. And I give it a good soaking! Is this normal? My cherry trees and apple tree located near it are just fine (touch wood.) Just this blasted tree. Any other suggestions???

  • david52 Zone 6
    11 years ago

    I have had that same problem, a single plum tree and two cherry trees, and this year, I sprayed just after the trees flowered and the new leaf buds were just starting.

    Made all the difference in the world. Now, the predator population is high enough to keep the aphids in check.

    I did have to re-spray the plum about a month later in early June, but thats it.

  • bob_in_colorado
    11 years ago

    Another alternative is a product called Pyola. It safe up to the day of harvest and kills insects in every stage of life. Larval and beyond.

    Chrysanthemum extract and canola oil. Mix with water and spray.

    http://www.gardensalive.com/product.asp?pn=8101

    I've used it. It's very good.

  • albert_135   39.17°N 119.76°W 4695ft.
    10 years ago

    How does one spray the curled bunches of leaves with the black infestation?

    The strongest spray does seem to remove them all. Does one spray daily? In the morning or evening? If one sprays with soap will those not removed be hindered from spreading?

  • david52 Zone 6
    10 years ago

    For those curled blobs with the black aphids, the only way I've found to deal with it is snip the whole mess off, then when the tree starts up with new growth, start to spray it.

    I use a pesticide called 'Eight" - see label at the link

    In the future, read up in this thread to see when to first spray them. Those curly balled up aphids are a serious pest and will stunt the tree growth.

    Here is a link that might be useful: .pdf of the label

  • highalttransplant
    10 years ago

    I never got around to spraying the trees this spring, and I am paying for it now. The peach tree has the curled up deformed leaves. Even though I can't see any aphids on them, it sure looks like they have been there. I saw a ladybug on there yesterday, so I guess nature is trying to balance things out, but you're right, David, it's definitely going to set the tree back this season. Oh, plus, not a single peach on there.

    The leaves on the apple trees look okay, but I know they will have their own set of problems later in the season. Last year, the birds pecked holes in every single apple, and the wasps moved in to finish the job!

    I'm starting to think that fruit trees aren't worth the effort ...

  • david52 Zone 6
    10 years ago

    I have over a dozen fruit trees, and last year they all bore fruit. It was sorta over-whelming. But we managed to freeze, can and dehydrate all of it.

    I think the best were the apples - everything I have, with the exception of Pink Lady, are varieties that you can't find in stores. Just fantastic tastes. I need to figure out a way to store them for months fresh - I know it can be done.

    This year, we had a brief warm up, things flowered, then it got cold again, then warm again and many of them flowered, not as prolifically, again. So I'm going to get a small crop this year as well.

    No peaches. We only get those once every 5 years. And apricots, well, my tree is 15 years old and I've had 15 apricots.

  • ad3333
    10 years ago

    I have several strawberry trees (arbutus unedo) in San Diego that recently were infested with aphids and the dreaded sooty mold. Being new to gardening, I was looking for an alternative to harsh pesticides. After researching here, I tried a mild pesticidal soap using a hose end sprayer (the kind that automatically mixes the dilution of a mild liquid soap like Palmolive or Ivory at about 3 tablespoons per gallon) as a spray bottle wouldn't have reached the top of these 15-foot trees.

    I was skeptical at first but was very pleased that this actually worked. I applied early in the morning and then rinsed thoroughly in the evening; I have read that spraying during the middle of the day can cause sunburn on the leaves. I felt like I was giving my trees a bubble bath but sure enough, this actually worked and the hose end sprayer made the application very easy.

    Reading that eggs will remain and hatch within a week, I did notice a few tiny aphids a week later and re-applied. It sounds like it is important to treat 2-3 times, about 1 week apart, to kill off hatching eggs and avoiding another infestation.

    So far so good, the flowers on the tree have returned and new leaves have emerged. I will use this easy and mild treatment every time moving forward.

    Thought I would share my experience...

  • digit
    10 years ago

    Very Good to Know. After reading this, I went back into the kitchen to share my first Pantano Romanesco tomato with DW.

    As I'm washing the cutting board, I realize that I'm using Palmolive Green dishsoap . . .

    Six and a half years . . . do you realize that kids came home from the 1st grade yesterday who weren't even born when I suggested that, Boris Yeltsin had just died, and Rupert Murdoch had just purchased Dow Jones & the Wall Street Journal? (Nothing much changed around here. ;o)

    Steve

  • amester
    10 years ago

    Just wanted to point out that there's a difference between the regular soft-bodied aphids and woolly aphids - which do you have? If they're woolly, the spray of water will get rid of them in the short term. But woollies will have a host plant to overwinter on and show right back up on your trees in the spring. I kept blasting and NEEM-ing my apple tree to pieces until I realized that an old, ragged rosebush was hosting them - I dug it up, tossed it, and haven't seen a woolly in two years. Had I not wanted to toss the rose, I'd have probably gone the Eight route. I'm as organic as they come, hate chemicals of every kind but they were horrible.
    Best of luck!

  • ad3333
    10 years ago

    I'm pretty sure they're soft-bodied, the house and trees are all brand new. So far so good after the second dish soap bubble bath, I haven't seen a single aphid and the strawberry trees are flowering just two weeks post-treatment. I'm still shocked the diswashing soap diluted with water worked as well as it did in killing aphids - I also read somewhere to be sure only mild is used, which is why I chose Palmolive and Ivory - no degreasers like Dawn or others.

  • dm_kelly
    10 years ago

    This was an interesting thread read. I never had aphids until last year. My plan of attack was to rip out the veggies (they LOVE my brussels sprouts), use insecticide which I'm opposed to, and trim the infected leaves off of the fruit trees which was very time intensive and made for an ugly tree. I like the blasting them with soap water option because my small infestation from last year only got bigger this year.

  • ad3333
    10 years ago

    Just a quick update - I've had to re-treat after a month or so but the aphid population is far less and it's so easy to re-treat. I've also caught the recent influx before they could cause damage as I have learned to have an eye for them now. They are born pregnant (literally!) and reproduce within a week. I suppose it's all about catching them early and keeping the population low, whether using pesticides or soap. I definitely like the idea of not using pesticides for this insect, the soap definitely works. And with the hose-end sprayer that blends the proper dilution of soap and water, it only takes a few minutes. Glad I found this thread!