Here is another picture of the grub damage.

The dreaded Squash Vine Borer strikes again. We refer to it as SVB, or @#%&*. It's a tough one to deal with, but if you put it in the Search Bar you'll find a bunch of info. I'm not growing squash this year because of it.

Do a search on this board and google for "squash vine borer" and "SVB". You will find multiple posts on this pest. It attacks squash, zucchini, pumpkins and sometimes cucumbers. I had it last year and am battling it this year. The short version - a moth lays dozens of eggs on the plant in multiple places. It aims for the base of the plant, but you can find them anywhere. They are brownish red and the size of a pinhead. The egg hatches and the borer works its way into the plant. It feeds on the main vine, gets to be about an inch or so long, exits the plant and then burrows into the soil to form a cocoon. It then reemerges as a moth and the cycle continues. In the south there can be multiple generations. In the north it is usually limited to one generation.

You can try burying the stem where you have removed the borers and mound dirt over it. It may form new roots and the plant could eventually recover, but I didn't have luck with this method. The plant was too stressed and never produced more female flowers.

I'm sorry - this is a difficult one to control. The only real way to eliminate it next year is to plant in a bed where you haven't had squash or zucchini before and grow under row cover. There are lots of other things people have tried, but with mixed results.

This post was edited by lam13 on Sun, Jun 23, 13 at 13:00

The embryonic fruit is right behind the flower bud. The male flower is on a stem.

Depending on where you are, you may have time to start a new crop of zuks that will be safe from the borer.

Your notion that the grubs are in your soil getting ready for next year is all too true. If the vines die, pull them and put them in the trash, not compost.

You will also want to carefully inspect your plants for additional eggs and remove them before they hatch. Last year I had my first generation in June. I buried the vines and thought I was in the clear. They reappeared in the first week of July. That was when I gave up and pulled all the plants. :(

Here is a picture of an egg. You can see the moth was able to lay the egg through the tulle row cover I tried. Next year I'm going to try growing solid stem varieties. They are supposed to be somewhat resistant.

I haven't ever had to deal with SVB's -- powdery mildew usually does in my cucurbits. But, I've read of people injecting(with a hypodermic) BT or Spinosad into the vine to control them. Booth products are OMRI listed and I'm sure the LABEL "police" are going to jump on this post(the same people that were hall monitors in grade school).

It's up to you if you want to use the product as mentioned above.

Good luck.

Kevin

Rpost78, welcome to squash frustration. I call this thing he-who-should-not-be-named. I inspected my plants daily and sighted my first egg on June 10 down here on the Texas Gulf Coast. I understand we have two generations down here but I don't know if you do in the central part of the state. I spot-spray eggs as I see them, checking every evening, trying to reduce their numbers; every other evening I spray the main vines heavily with Bt and a little spreader sticker till they are dripping on the theory that keeping it available as much as possible will mean they will ingest some when they start eating into the vine; every weekend I inject the vines every three inches with Bt solution as the final blow since I doubt I caught all the eggs in the preceding week. Some people scrape them off but my fine motor skills aren't that good so I resorted to the spray. In other years I would have lost my plants by now but they are still looking pretty good (of course, now that I've said that, they'll probably die this week...).

Do we get them here in the West Coast area? I've never really seen this problem.
I think I would rather buy them than go with the squirrelwhisperer route! Is it really worth all that spraying to have squash that is very inexpensive? Just my 2 cents. Nancy

Nancyjane: Not sure. I read about them every summer, but it's usually from people in other parts of the country.

I spray BT all summer long because of cabbage loopers and hornworms and since I only have a few cucurbits going usually, I give them a spray also. And since BT doesn't harm beneficials one bit, it can't hurt.

Kevin

I tried the Injecting the stem with BT method a few weeks ago, and it seems to have stopped the SVBs I had dead in their tracks. I haven't reapplied every week, but I am keeping a close look out for new eggs and the frass the SVB leaves behind. I'll probably inject again next weekend just to be safe.

I'd be surprised if there aren't any SVBs left in the vines you haven't cut into. Keep a look out for additional frass and if you see any you'll want to get at the @#%&* fast.

Nancyjane-I totally agree with the question of whether all that effort is worth it. At this point I'm doing it mainly to satisfy my curiosity about whether it could work, and also trying to discover if the eggs will stop appearing, which will give me a handle on the timing of moth generations where I live, something I have surprisingly been unable to ferret out on the internet. Summer squash were an afterthought this year, I had extra containers and soil and just figured I'd throw some seeds in. I never imagined they'd get so big and healthy looking, but once that happened, I felt like I was on the hook to do what I could to keep them going. I picked the soap and Bt because they looked the least toxic. I can't imagine what commercial growers put on their squash crops to keep this thing from bankrupting them. Probably something I don't really want to know.

I will definitely look into purchasing BT. (Now that I know what it is;)) I will be checking for eggs today. I had looked previously, but wasn't quite sure what they looked like!

Last year, I was able to grow a bunch of veggies and never once used any type of pesticide. This year I have new soil and different (bigger) raised beds, but the moths must have caught on. I suppose they could have come here with the plants I bought from Home Depot. I didn't start from seeds with my zucchini and squash. Got a bit of a late start this year!

I realize I am jinxing myself, but this year I planted Seminole pumpkin (winter squash) and tatume squash (summer or winter)--and both seem to be resistant to SVB so far!
In the past, I was able to get a squash harvest by cutting out the borer and burying the damaged stem with lots of topsoil and compost.

IM13 I can't believe she was able to lay eggs through your tulle, I am trying that method for the first time this year and was feeling this may be the best combatant effort yet but your discouraging me lol. I am out frequently but haven't even seen the moth yet but she is due.

RPost78,
Yes definitely you might have brought them with you from Home Depot. I have seen the actual SVB moth flying around at the nursery in my neighborhood Home Depot.

Rich_manure: I know!!! I thought I really figured it out with the tulle netting. However, I think I had it too tight against the leaves. If I had it to do over again, I would get a larger piece (I think you can get it 108" wide) and float it higher using poles or sticks to keep it above the leaves. This was my setup about a month ago:

I just skewered one!

{{gwi:67744}}

This year I am growing Romanesco Zucchini which is supposed to be more resistant. The stems seem to be a bit thicker skinned. Still this one got through. It's not on the main branch and if I lose that one part, I will be ok. I am going to try the injectable BT since I'm also growing Butternut Squash and I don't want those to get ruined.