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captainspeedy

svb - sb: how to clear the soil?

captainspeedy
15 years ago

Last year, we were hit with the SVB and the squash bug in our zuchini and spaghetti squash. They hit zuchini the year before that, too.

How do I ensure they're eliminated from the soil before planting this year? Is there a pesticide I can mix into the soil now which won't kill the seedlings two months from now?

I want to make sure I have the best fighting chance against the buggers this year!

Comments (18)

  • jean001
    15 years ago

    They're not in the soil

    Read this
    http://www.ca.uky.edu/entomology/entfacts/ef314.asp

    Here is a link that might be useful: SVB

  • jwstell42
    15 years ago

    Umm, I just read the article you linked Jean and it specifically mentions that it is in the soil :)

    "This insect overwinters as a full grown larva or a pupa one to two inches below the soil surface. If it has not already done so, the larva pupates in the spring. Adult moths begin to emerge about the time the plants begin to run, and moth flight continues through mid August. "

    Sorry I don't have an answer for your captain, just wanted to point out the inaccuracy of the above post.

  • glib
    15 years ago

    I think Jean meant "garden soil". They are in the garden, but they will also fly in from a nearby fencerow. By far the best way to clear a garden soil of all pupae, slugs, and earwigs (together with some worms and roly-poly) is chickens before and after the growing season.

  • wayne_5 zone 6a Central Indiana
    15 years ago

    SVB.......grin and bear it?! LOL
    I plan to spray some Surround clay this year to see if that helps on some of them.

  • Belgianpup
    15 years ago

    Maybe this info from ATTRA will help (see link below).

    Sue

    Here is a link that might be useful: ATTRA - organic SVB & SB control

  • knittlin
    15 years ago

    I've been researching this and have decided to try covering with lightweight floating row cover until female blooms show up, then uncovering for the rest of the season. What I understand is this won't stop the SVBs completely, but will keep the adult moth from laying eggs until the plants are mature enough to withstand a borer attack.

    The botanist at work (organic-only nursery) was listening in when I was telling a customer this, and he said it's what he does. He added that by that time, the plants are large enough to handle slitting open the stalk to remove the borer (something else he does that I will try as well).

  • sunnibel7 Md 7
    15 years ago

    For what it's worth, I have gone slit the vine to get rid of the borers with an 80% success rate. (The failure was due to being unable to find the borer in the stem.) Surprisingly, slitting the stem, then mounding some nice compost or other "fluffy" soil over the cut stem, followed by a little extra water for a week doesn't kill the plant. And once I get rid of the first set of borers I don't seem to get any more in a season. If you know about when they show up each year (I keep a journal)keep an eye on the stems for that little tell-tale sawdust they leave behind around that time. Not only is this method organic, but you don't need to spend any money at all!

  • knittlin
    15 years ago

    That's what Neil the botanist said to do as well, Sunnibel ~ mound dirt over the cut.

    80% success rate? Guess manual removal really does work! :)

  • yardenman
    15 years ago

    I would scratch up the soil to uncover the pests for 2 weeks, cover the area with clear plastic for 6 weeks to solarize/sterilize it, then repeat.

    Anything you can do to disrupt a pest's lifecycle will seriously reduce it, if not eliminate it.

    Then rotate your crops and put floating row covers on them to prevent new infestation.

  • Katxena
    15 years ago

    sunnibel7, when you say they are small, how small do you mean? I just want to know what I should be looking for, because I had trouble with them last year too.

  • sunnibel7 Md 7
    15 years ago

    Katxena- Well, I'm not too sure how small they are at their smallest, but the ones I've found really close to the little hole are about as long as a grain of rice (but skinny like the hole), maybe a little smaller. The big ones are like... um, more than twice as long and really fat. They were pretty easy to spot because they were white with a black gut and the only thing in there that was wriggling around. They also leave a trail of sawdust behind them inside the stem, which I also cleared out. I think you could use a q-tip if you don't want to touch them. They are pretty yucky looking! Good luck!

  • digdirt2
    15 years ago

    Just to clarify a point on SVB that Jean referred to, quite correctly, but may have been misunderstood.

    It is not the pupae in the soil that do the damage. At least not directly. ;) They hatch into moths, the moths, days later lay eggs on the base of the stems and it is the larvae that hatch from those eggs that bore into the plants and do all the damage.

    Now granted, tilling to kill the few pupae in the soil may be somewhat beneficial, but this does not mean you won't still have problems with SVB. The moths can fly in from anywhere, even miles away, lay the eggs and 6-10 days later is when your problems begin.

    This is why the most effective control measures are directed at protecting the crop rather than treating the soil Pesticides aren't very effective at killing soil pupae. Instead, one can either plant trap crops of hubbard squash away from the garden, time-plant to avoid the moth cycle and hatch dates which works well in some parts of the country, or cover the plants so the moths can't lay eggs. Primary controls are NOT directed at soil treatment.

    Secondary controls after the larvae hatch such as slitting the stem to remove the bore, stem wrapping, burying the stems, etc. can also be of great help in saving the crop.

    Squash bugs are a different matter entirely. There is no soil treatment for them although again tilling is beneficial. The adults overwinter in cucurbit fields under crop debris, clods of soil, or stones but adults also are found in nearby wood piles or buildings. But again they can fly in from far and wide.

    They lay eggs - easy to spot orange ones - on the under sides of the leaves. Egg patrol, finger squishing of the eggs prior to hatching, various pesticides on the adults and nymphs, and even dust buster vacuum cleaners are effective controls. ;) But covering with Reemay or any of the other insect barriers is especially effective but hand pollination is then needed - easy to do - but required.

    Hope this helps.

    Dave

  • swjonthebay
    15 years ago

    The *dreaded* SVB has been a garden nemesis of mine for the past several years to the point I wasn't going to even plant squash this year because of them! And I've wondered (out loud even here maybe?) how much good row covers would provide if the larvae were already present in the soil where the squash were to be grown. Wouldn't that trap the emerging moth in there with your beautiful squash plants?!?!?

    But, oh happy day! I found this today...an organic SVB pest control. No having to lay off planting squash for a year to "clear" the soil of larvae :)

    Fingers crossed hoping this works!

    Here is a link that might be useful: Monterey Spray

  • bella_trix
    15 years ago

    I have some pictures that might help if you are trying to split the vines for SVB.

    The cup is about 2" across. SVB can be smaller and it is better if you get them out when they are small. I made a small long-wise split and then fished around inside the vine with a small hooked wire.
    a{{gwi:28590}}

    Be on the look out for frass. It's a sign that the evil critters are in the vine.
    {{gwi:28591}}

    I was somewhat successful with a combination of splitting the vines, injecting with BT (Bacillus thuringeinsis - it's organic) and injecting with beneficial nematodes. I posted this a while ago, but this was my method:

    "I tried spraying the plants down with BT, but I think I discovered the borers too late. It might have helped with later infestations, but I don't know. I used Thuricide mixed 4T to a gallon. Wear goggles when you spray it! It irritates the eyes.

    I also injected BT directly into the infected vines. I mixed it at 1 teaspoon BT to 1 cup water and injected 1ml at each spot. I used an 18g needle and 3ml syringe. They are available from any farm and ranch/livestock catalog or feed store. I also tried injecting predatory nematodes into the zucchini vines. I mixed it up as instructed, transferred to the sharp needle (the one it comes with is useless) and injected .5 to 1 ml per spot. THIS IS IMPORTANT: wear safety glasses/goggles when injecting. The squash vines will clog the needle occasionally and, when that happens, the needle comes away from the syringe and the bt or nematodes shoot back directly into your face. It is not any fun flushing your eyes out for 20 minutes and then frantically searching the internet to find out if the nematodes are about to eat your eyes (they won't, there have been accidents at the facilities that grow the nematodes and everyone is fine). Also, do not dispose of the needles directly into the trash. Drug stores sell containers for used needles (for insulin needles).

    Something worked, but I don't know if the nematodes or BT did the job. It definitely saved my African and Delica winter squash. Unfortunately, some of my squash were too far gone to recover.

    I'm going to try it again next year and attempt row covers for the time period when I had problems."

    As a side note: a the end of last year I decided to dig through my squash beds and pick out all the SVB cocoons. I found SVB-sized rocks, SVB-sized pieces of wood, SVB-sized chunks of clay, a million interesting bugs, but not one SVB cocoon. And I REALLY searched. My only guess is that the nematodes either really did get all the SVB in the vines or they went down into the soil and ate the cocooned SVB.

    Hope this helps and happy SVB destruction,
    Bellatrix

  • glib
    15 years ago

    Aha. Sunnibel tells me something I did not know. I have used the "fish around with a hook" technique and I only got maybe 30% success. Reason: if you go blind, and you can not see the entry point, you have a low chance of getting it. I was making slits barely big enough to get the hook in. But making a long slit on the visible side of the vine, and opening it up for inspection, should result in a much bigger probability of seeing the larva.

  • knittlin
    15 years ago

    Thanks for the further instructions, Sunnibel. And the pictures were excellent, Bellatrix. I appreciate all the new information, ya'll. :)

  • sunnibel7 Md 7
    15 years ago

    You're quite welcome! I have so many things I look up in the forums that it's a pleasure to have an anwser for others every once in a blue moon! And I want to say thanks for the pictures too. Those guys are about as big as I've seen them. And you can clearly seen in the second picture the "sawdust" I was talking about. Wonderful photos!

    As for catching them earlier, I know that mine show up in early July, so I start looking at the stems every morning from June 26 onward. I bet the injection of Bt would work great, especially if you were monitoring the stems so you got it in right away.

    Happy Squashing!