Squash Bugs and Squash Vine Borers - What I Learned This Year
 

Each year I learn a little more with having a garden. This is my 3rd year.

The first year I knew nothing about the squash bugs and the SVB'ers.

Last year I thought the squash bug eggs I was seeing were the SVB eggs and that the squash bugs I was seeing were stink bugs. I did know about the SVB worm that would eat from the inside out and was able to pull out quite a few with my trusty crochet hook (one of the tiniest ones made)

So this year, I learned a lot. I learned that it's not good to plant your squash near where you put mulch. And the landscape timbers that are holding the mulch in place, well, the squash bugs love hiding in the mulch and under the timbers.

I have a carport and then a hill. This past year I put double ground mulch near at the top of the hill and the landscape timbers. Right below that I planted my winter squash crop (previous years I've had melons in this area).

I started seeing eggs in May. I quickly started removing them with lint tape. It's been a day in and day out process and struggle. After a while, when you have so many squash plants, and they start running, it's a bit hard to try to find where the SB's are laying there eggs if they aren't doing it on the top. But I'm vigilant, though I don't get them all. I've found eggs on blades of grass and even underneath the timers. I turn over the timbers and collect the little buggers in an old water bottle, or something of the like.

I've learned, if you see a mass of eggs, there is most likely another mass somewhere really close by. I've gotten good at finding the nymphs that have survived my lint tape removal and getting those off in mass, or just plain squishing them when I see them. I've gotten a lot less squeamish with catching bugs by hand and killing the nymphs this year!

It also seems that when you water on a hot day, they come out in droves. One day I did that and I must of easily caught 50 of them in one shot.


The SVB, there's not much I can do, they are too fast and too many. They are still out there laying their eggs. This is late for them compared to last year. I have pulled out a good 50 worms from my plants. About 6 a succumbed to their death from the borer, unfortunately.

I've tried to stay away from pesticides. The only thing I've used on occasion is insecticidal soap.

I can't even imagine what it would be like for next year if I didn't do what I've been doing with removing the eggs, and the SB when I see them. I've removed thousands of eggs, and hundreds of SB's. I have the winter squash crop on the hill but I have 4 raised beds of squash that are down in my actual garden. Those too have to be watched, but they've taken second fiddle to the ones on the hill.

Just thought I'd share my experience. Not a fun one. If I didn't love winter squash so much, I'd of given up. I usually plant squashes that are unusual. Next year I will be even more selective of what I grow. No more zuchinni and I will not try delicata again - 3rd year and no luck. Only summer squash I will probably grow is patty pan. I will grow some winter squash as summer - they seem to do very well doing that.

This was also a year for me about trying to effectively deal with SVB. I had a Patio Star plants in two, 14" planters. I inspected the stems consistently at least every other day, and still got SVB on one plant, even though I never found any eggs. ??? On the other plant, I coated the bottom ~4" of the stem with "Tangle-Trap" sticky coating. I reapplied once. I mainly wanted to see if it damaged the plant, and I could see no issues with that. No SVB on that one, but may or may not have had problems with that plant anyway. Not really an endorsement, and try at your own risk, but seemed to work good for me. I will coat all lants next year. I still found that my "good" plant (with no SVB) ran stopped producing about mid-July. That may be par for that variety in a container. But anyway, I got two to three more weeks of production than I usually do. BTW, I'm a fan of Patio Star for containers. Next year, I'll have another plant ready to go about the first of July.
-GG

[QUOTE=Greatgardens;587570]I inspected the stems consistently at least every other day, and still got SVB on one plant, even though I never found any eggs. ???[/QUOTE]

They can get sneaky and lay eggs on a leaf. They also sometimes lay eggs right under the soil line where they're hard to see. I inspect plants and pick off eggs by hand, but I also spray spinosad or Bt around the base--really drench every surface on the base of the vines and let some drip down into the soil right around the base to make sure the vines are covered just under the soil line. That seems to do the trick. I did get a borer further upstream in one plant in the hollow stem of a leaf higher up than I would normally spray. Saw one wilted leaf on an otherwise healthy plant, checked it, and saw the tiny bore hole. I injected concentrated spinosad into the hole just in case the borer was making its way down to the main vine. Seemed to do the trick.

Great! I'll keep that in mind for next year.

Edit: I wonder if it would be possible to breed a zucchini-type plant with solid stems? Probably the stuff of genetic engineering which would turn a lot of folks off. But seems like that would take care of the borer issue.

-GG

I also have terrible SVB issues. You have been very vigilant but the onslaught is relentless. :no:

Tromboncino is a solid stem [I]C. moschata [/I]that can be used as a summer squash/zucchini type when young or a winter squash if left to mature. Also a great conversation starter when grown to full length!

I've tried wrapping stems in aluminum foil, but not the tanglefoot or spinosad treatments. All great ideas, along with getting bush style plants started under row cover.

Keep sharing your experiences, and good luck next year! :)

[QUOTE=eldemila;583388]Each year I learn a little more with having a garden. This is my 3rd year.

The first year I knew nothing about the squash bugs and the SVB'ers.

Last year I thought the squash bug eggs I was seeing were the SVB eggs and that the squash bugs I was seeing were stink bugs. I did know about the SVB worm that would eat from the inside out and was able to pull out quite a few with my trusty crochet hook (one of the tiniest ones made)

So this year, I learned a lot. I learned that it's not good to plant your squash near where you put mulch. And the landscape timbers that are holding the mulch in place, well, the squash bugs love hiding in the mulch and under the timbers.

I have a carport and then a hill. This past year I put double ground mulch near at the top of the hill and the landscape timbers. Right below that I planted my winter squash crop (previous years I've had melons in this area).

I started seeing eggs in May. I quickly started removing them with lint tape. It's been a day in and day out process and struggle. After a while, when you have so many squash plants, and they start running, it's a bit hard to try to find where the SB's are laying there eggs if they aren't doing it on the top. But I'm vigilant, though I don't get them all. I've found eggs on blades of grass and even underneath the timers. I turn over the timbers and collect the little buggers in an old water bottle, or something of the like.

I've learned, if you see a mass of eggs, there is most likely another mass somewhere really close by. I've gotten good at finding the nymphs that have survived my lint tape removal and getting those off in mass, or just plain squishing them when I see them. I've gotten a lot less squeamish with catching bugs by hand and killing the nymphs this year!

It also seems that when you water on a hot day, they come out in droves. One day I did that and I must of easily caught 50 of them in one shot.


The SVB, there's not much I can do, they are too fast and too many. They are still out there laying their eggs. This is late for them compared to last year. I have pulled out a good 50 worms from my plants. About 6 a succumbed to their death from the borer, unfortunately.

I've tried to stay away from pesticides. The only thing I've used on occasion is insecticidal soap.

I can't even imagine what it would be like for next year if I didn't do what I've been doing with removing the eggs, and the SB when I see them. I've removed thousands of eggs, and hundreds of SB's. I have the winter squash crop on the hill but I have 4 raised beds of squash that are down in my actual garden. Those too have to be watched, but they've taken second fiddle to the ones on the hill.

Just thought I'd share my experience. Not a fun one. If I didn't love winter squash so much, I'd of given up. I usually plant squashes that are unusual. Next year I will be even more selective of what I grow. No more zuchinni and I will not try delicata again - 3rd year and no luck. Only summer squash I will probably grow is patty pan. I will grow some winter squash as summer - they seem to do very well doing that.[/QUOTE]

I admire your diligence! I have decided that I do not love zucchini/squash enough to battle these devils. My first plantings were destroyed by them, despite my efforts at removing them. I thought I was so smart this year, I had the backups ready and planted them first week of July in new soil. Applied DE to the stems and all was well in the beginning. Then the wilting began :cry: . I just pulled them and here is what I found :twisted:

In all 4 plants. Maybe it is my growing conditions, timing, or some other error on my part but I am finished with squash. I will be quite content purchasing mine from produce stand. The SVB's have won the battle:))

Jillian

[QUOTE=jillian;587887]Applied DE to the stems and all was well in the beginning. Then the wilting began :cry: . I just pulled them and here is what I found :twisted:

In all 4 plants. Maybe it is my growing conditions, timing, or some other error on my part but I am finished with squash. I will be quite content purchasing mine from produce stand. The SVB's have won the battle:))[/QUOTE]

FWIW, DE isn't really for soft-bodied insects. It works on hard-shelled insects because it abrades their exoskeletons and removes the waxy coating that protects them, then they desiccate. It doesn't always work well on soft, flexible-skinned pests like caterpillars and grubs.

And for people who don't like to use pesticides because of possible harm to non-pest organisms--DE is actually more broad-spectrum than Bt. DE will harm anything that has an exoskeleton, which means most pollinators and predatory insects. But Bt is very specific. BtK harms only moth and butterfly larvae, i.e., caterpillars, including the squash borer caterpillar. (BtI harms only the larvae of long flies like mosquitoes, blackflies, etc.). So it's actually less of a "pesticide" than DE and, unlike DE, it will actually work on borers [I]if you spray the plants at the right time[/I]. The caterpillar has to eat the Bt for it to work--it's not a contact pesticide--and Bt doesn't kill its targets immediately. So Bt has to be on the vine when the borer starts boring into it so that the borer actually eats the Bt. It won't prevent the borer from boring, but it will hopefully kill the borer before it can eat through a lot of the vine and do enough damage to hurt the plant. If your timing is off, though, and the Bt has worn off or gotten washed off when the borer hatches and starts eating into the vine, it won't work.

In my experience, you should apply it at a higher concentration than the bottle indicates to the bases of the vines every few days once you start seeing eggs and reapply immediately if it rains. If you have a lot of plants, you won't get them all, as there will still be windows of opportunity for borers to get in if they hatch right after the Bt was washed off by rain or if you missed a spot or something. But it should help more than DE.

I've actually been wondering whether it might work to spray the Bt, then coat with vaseline or something on top after it dries to protect it from wearing off/washing off so quickly. But I have no idea whether that would inactivate the bacterium or what.

Spinosad is somewhat more broad-spectrum than Bt, so I use it sparingly. I think only at the bases of squash plants is a good use for it, since it doesn't come into contact with pollinators at all and covers a limited area on the plant.

I have asked this same question on another thread but will ask again here: does anyone know if Met52 is effective against squash bugs? Also, could someone explain the difference between squash bugs and 'squash vine borers' as that is a new one to me.

[QUOTE=creeker;587912]I have asked this same question on another thread but will ask again here: does anyone know if Met52 is effective against squash bugs? Also, could someone explain the difference between squash bugs and 'squash vine borers' as that is a new one to me.[/QUOTE]

I can't answer re: Met52 as I'm not very familiar with it. My impression is that it's not as thoroughly tested as some other biopesticides, and whether or not it harms beneficials is up in the air.

The difference between squash bugs and SVBs:

[url=http://www.extension.umn.edu/garden/insects/find/squash-bugs/]Squash bugs[/url] are true bugs that suck sap out of leaves and sometimes fruit.

[url=http://www.extension.umn.edu/garden/insects/find/squash-vine-borers/]Squash vine borers[/url] are the caterpillars of a red and black moth. They bore into the stems of squash plants and kill the vine by eating the inside of the stem. You often can't tell they're there until your squash plants wilt catastrophically overnight at which point, there's usually not much you can do to save them.

Thanks much Gorbelly. Its squash bugs that drive me nuts. I had 30 squash plants in a row that yielded great in June and part of July this year. I thought I had lucked out til those buggers hit and wiped my plants out in about 3 weeks. Nothing I tried would stop them. Think I'l try tromboncino (spelling?) next year.

[QUOTE=creeker;587948]Think I'l try tromboncino (spelling?) next year.[/QUOTE]

Just a heads up: tromboncino vines are BIG. Like 25 feet long big. So make sure you plan the space accordingly. I actually grow one of mine up a trellis against the garage wall. The vines took over the trellis and are now colonizing a good 8 foot stretch of the railing on the garage roof. I have another one on a trellis in a bed, which was a huge mistake. I've had to cut it back several times just because I simply don't have the space for it to run free. I was so miffed at having to cut the vines that I steamed the leaves and ate them as [url=https://en.wikipedia.org/wiki/Ssam]ssam[/url] to make myself feel better about the waste.

Some people have reported low production with their tromboncino. I ordered [url=http://www.growitalian.com/products/Zuchetta-Tromba-d27Albenga.html]Franchi seed[/url], and my vines are pretty darn productive as long as I water them very generously and feed them a lot. Unlike the hybrid vining ball squash I grew in past years, these really protest if you let them get hungry or thirsty and will sulk and drop their female buds unless you stay on top of watering and feeding. But if you're diligent, they produce well.

OK,thanks for the advice, they sound real interesting. I may have to plant them on the back forty so they have plenty of room. Ron

My tromboncino "only" grew to 8 ft, but they were vigorous.

I have seen them trained over a hoop cattle panel trellis so the fruits hang straight down - I think little kids would find that magical (too :lol: )!

[QUOTE=creeker;587966]OK,thanks for the advice, they sound real interesting. I may have to plant them on the back forty so they have plenty of room. Ron[/QUOTE]

If you let them run on the ground, they should be pretty bulletproof where borers are concerned. They root aggressively at every node, so it would be really hard for even the notorious SVB to kill the plants. And as a bonus, you'll get them curling in that interesting french horn shape.

Trellising them gives up some of that resistance (and also may be why mine are so sensitive to not being watered and fed constantly, since all the nutrition and water is coming from one main root system and traveling 20+ feet), but I have to because of limited space, and taking the extra steps to protect the vines from borers isn't too much of a burden with my small number of plants and the fact that we only get 1 generation of borers here.

I don't think they have any special resistance against squash bugs--I've just heard that squash bugs just don't like them as much as other kinds of squash.

[QUOTE=PhilaGardener;587967]My tromboncino "only" grew to 8 ft, but they were vigorous. [/quote]

What a lot of people sell as zuchetta rampicante or tromboncino is probably lots of slightly different varieties from different regions and original seed sources.

[QUOTE=PhilaGardener;587967]I have seen them trained over a hoop cattle panel trellis so the fruits hang straight down - I think little kids would find that magical (too :lol: )![/QUOTE]

Ha! They get a lot of exclamations when I give them away. People seem to enjoy their weirdness.

What you think is the squash vine borer isn't. You are picking off Squash bug eggs, they will lay eggs on and under leaves in little clusters of brownish red color. The adult of the svb looks like a wasp/moth. The svb has a different lifecycle from the squash bug.

See the pictures of them in this link:

[url]http://www.extension.umn.edu/garden/insects/find/squash-vine-borers/[/url] this is really full of great information!!!

What helps is to plant your squash plants later in the season by a month or more. That way the adults (red looking moth/wasp that when it flies is noisy) that lay the eggs will be all done.

Or you can use row covers if you start the plants as soon as your soil warms up in the spring.

It also seems that when you water on a hot day, they come out in droves. One day I did that and I must of easily caught 50 of them in one shot.

What you wrote:
"The SVB, there's not much I can do, they are too fast and too many. They are still out there laying their eggs. This is late for them compared to last year. I have pulled out a good 50 worms from my plants. About 6 a succumbed to their death from the borer, unfortunately."

My question, what is it that you are saying are too fast? a bug or a worm? When do you "see" the SVB? It isn't the SVB that lays the eggs. I think you are still seeing something other than SVB which is the larva (worm) which doesn't lay eggs, but grows inside the stem of the plant.

Here is a link that shows infant white and black adult squash bugs that do move fast in a video:
[url]http://extension.umd.edu/growit/insects/squash-bug[/url]

Good luck with your zucchini growing next year.


zeroma

I have fought the SVB for years and tried all of the remedies like foil around the stem to no avail. Here is what works for me.

I purchase Thuricide which is a bt solution made by Bonide.

I dilute it as recommended on the bottle and use a syringe with an 18 gauge needle to inject it into the squash stems about 6 inches above the soil level.

Since the stems are hollow, the solution runs down the inside and coats them and any SVB caterpillars that are present. You can wait until you see signs of caterpillar poop (frass) but I usually inject after the plant starts to flower because I KNOW that those sneaky SVB moths will have laid eggs when I wasn't looking.

I also plant a second crop at about this time so that when/if the first crop dies, then I will have more producing.

This has worked well for me over the last 2-3 years and I have had plenty of zucchini which I really like.

Eldemila, your experience with vine borers and squash bugs this is exactly the same as mine. Too many and too fast. You definitely know what you are looking at and you definitely know what to do.:yes:

Zeroma, squash vine borers most definitely lay eggs! And anywhere along the vine, in singles, sometimes pairs, usually at the stem base but I have seen them laid near the end of a leaf stem. And the squash vine borers fly during the daylight hours even though they are moths. And yes, they are fast. They do not fly in a straight line but more of a zigzag.:x

[QUOTE=Nattybo!;588425]Eldemila, your experience with vine borers and squash bugs this is exactly the same as mine. Too many and too fast. You definitely know what you are looking at and you definitely know what to do.:yes:

Zeroma, squash vine borers most definitely lay eggs! And anywhere along the vine, in singles, sometimes pairs, usually at the stem base but I have seen them laid near the end of a leaf stem. And the squash vine borers fly during the daylight hours even though they are moths. And yes, they are fast. They do not fly in a straight line but more of a zigzag.:x[/QUOTE]

Yes Nattybo, I guess what I think of as the squash vine borer is the 'worm'/larva part of the life cycle and the adult that does the egg laying is the moth.

The adult moth does lay eggs along the stem of the plants. If I said it wrong, sorry, I was trying to explain but guess I didn't say what I thought I wanted to. Distracted with the dog poking his nose on the keyboard at the time wanting to go outside...didn't mean anything offensive. :oops:

[QUOTE=brownrexx;588412]I have fought the SVB for years and tried all of the remedies like foil around the stem to no avail. Here is what works for me.

I purchase Thuricide which is a bt solution made by Bonide.

I dilute it as recommended on the bottle and use a syringe with an 18 gauge needle to inject it into the squash stems about 6 inches above the soil level.

Since the stems are hollow, the solution runs down the inside and coats them and any SVB caterpillars that are present. You can wait until you see signs of caterpillar poop (frass) but I usually inject after the plant starts to flower because I KNOW that those sneaky SVB moths will have laid eggs when I wasn't looking.

I also plant a second crop at about this time so that when/if the first crop dies, then I will have more producing.

This has worked well for me over the last 2-3 years and I have had plenty of zucchini which I really like.[/QUOTE]

I'm just curious if you use good crop rotation with your method also? I like this method you describe.

[QUOTE=zeroma;588320]What you think is the squash vine borer isn't. You are picking off Squash bug eggs, they will lay eggs on and under leaves in little clusters of brownish red color. The adult of the svb looks like a wasp/moth. The svb has a different lifecycle from the squash bug.[/quote]

It's possible to pick off SVB eggs. They're quite visible down by the base of the plant, but they don't get laid in clusters. However, they can lay the stray egg further up or on a leaf or down just under the soil line, and you only need to miss one to lose a plant.

[QUOTE=zeroma;588320]What you wrote:
"The SVB, there's not much I can do, they are too fast and too many. They are still out there laying their eggs. This is late for them compared to last year. I have pulled out a good 50 worms from my plants. About 6 a succumbed to their death from the borer, unfortunately."

My question, what is it that you are saying are too fast? a bug or a worm? When do you "see" the SVB? It isn't the SVB that lays the eggs. I think you are still seeing something other than SVB which is the larva (worm) which doesn't lay eggs, but grows inside the stem of the plant.[/QUOTE]

My understanding was that "too fast" meant the speed at which the borer takes the plant down. They really do seem to kill plants overnight. One day, the plant looks fine. The next day, everything is wilting, and even doing SVB "surgery" only has a small chance of saving the plant. It seems like the borer just reaches a critical size one day and kills the plant overnight as opposed to in a way that gives you warning symptoms in time to do something.

[QUOTE=zeroma;588710]I'm just curious if you use good crop rotation with your method also? I like this method you describe.[/QUOTE]

I do rotate my crops but it really doesn't help for preventing the SVB. They can fly for up to 2 miles and my garden is not THAT big!


As for taking down a plant quickly -it's not really as quick as you think. The SVB takes several weeks from egg to large, plant killing larva. It just seems like the plant dies quickly because we don't notice that it is infected until the damage is already done and it is ready to die. The plant survives with the larva inside for several weeks. From the SVB's point of view, the plant has to survive long enough for the larvae to grow to a mature size so that they can pupate.

[QUOTE=brownrexx;588746]I do rotate my crops but it really doesn't help for preventing the SVB. They can fly for up to 2 miles and my garden is not THAT big![/quote]

I think crop rotation is really just the issue when you want to use a row cover strategy, right? Because if you don't rotate, you risk having moths hatching from pupae in the soil and mating and laying eggs anyway despite the trouble you've gone through to cover and hand-pollinate your squash.

[QUOTE=brownrexx;588746]As for taking down a plant quickly -it's not really as quick as you think. The SVB takes several weeks from egg to large, plant killing larva. It just seems like the plant dies quickly because we don't notice that it is infected until the damage is already done and it is ready to die. The plant survives with the larva inside for several weeks. From the SVB's point of view, the plant has to survive long enough for the larvae to grow to a mature size so that they can pupate.[/QUOTE]

Right. But from our point of view, it's easy to miss tiny bore holes, and it seems like the plant is a goner overnight. Even diligent and experienced gardeners experience the heartbreak of walking out one morning and realizing that the borers killed one of the plants that looked 100% fine the day before. It's not like a pest that takes down plants by defoliation.

[QUOTE=gorbelly;588750]I think crop rotation is really just the issue when you want to use a row cover strategy, right? Because if you don't rotate, you risk having moths hatching from pupae in the soil and mating and laying eggs anyway despite the trouble you've gone through to cover and hand-pollinate your squash.



Right. But from our point of view, it's easy to miss tiny bore holes, and it seems like the plant is a goner overnight. Even diligent and experienced gardeners experience the heartbreak of walking out one morning and realizing that the borers killed one of the plants that looked 100% fine the day before. It's not like a pest that takes down plants by defoliation.[/QUOTE]


This is true but I roto till once a year in the Fall which hopefully exposes the pupae to bird predation and death from the cold in the winter months. I tried row covers one year and still got SVB so now I use the bt as a preventative and it seems to work better for me. I also had trouble with row covers because the zucchini plants got so big that they created gaps in the covers and that is probably how the moths got inside and infected them. I had grown a parthenogenic variety that does not require insect pollination so I did not open the row covers to hand pollinate.




Yes, it definitely seems like an overnight event to us but according to PA State entomologists the larvae feed for 4 weeks before killing the plant. This is probably why I have good luck with injecting the bt into the stems before I even see any damage. if you wait until you see the damage, then it will probably be too late. I know that they will infect my plants so I inject the bt as a preventative. It is the only way I feel confident that I will have zucchini.

[URL]http://ento.psu.edu/extension/factsheets/squash-vine-borer[/URL]

[QUOTE=brownrexx;588851]Yes, it definitely seems like an overnight event to us but according to PA State entomologists the larvae feed for 4 weeks before killing the plant. This is probably why I have good luck with injecting the bt into the stems before I even see any damage. if you wait until you see the damage, then it will probably be too late. I know that they will infect my plants so I inject the bt as a preventative. It is the only way I feel confident that I will have zucchini.

[URL]http://ento.psu.edu/extension/factsheets/squash-vine-borer[/URL][/QUOTE]

Some people refuse to use Bt or don't know about it. All I meant was that, for many people, their experience of squash vine borers is that they seem to kill plants overnight. I'm not disputing that the SVB [i]actually[/i] takes a long time to kill the plant. If one is not aware of preventative methods that actually work (a lot of the "home remedy" methods don't), then the plant dies very quickly from the moment one notices symptoms, and that's just how I personally interpreted eldemila's original statement about how SVBs are "too fast".

I think your advice to inject Bt preventively is great. I'm not disputing that, either. A lot of advice sources say it doesn't work, but they generally are talking about injecting it after symptoms are noticed already, at which point, the damage is usually too extensive, and the plant is a goner no matter what 9 times out of 10. I've had luck with injecting Bt and spinosad at the first sign of a bore hole, but I don't grow more than 3 or 4 squash plants. I think checking over vines that carefully could be hard for people who grow a lot of squash. So your advice to inject it before borer activity is seen is a really good idea, especially for people who live in places where there are multiple generations of the SVB.

I interpreted the "too fast" as the SVB moths are too fast to catch. I have often seen one on a plant and I try to grab it to no avail. It's like trying to swat a fly with your hand.

Using bt is the only way I would ever get any squash. I have never tried spinosad but it's good to know that it works too. I only grow 4-5 summer squash plants.

browrexx...since you have this method under good understanding, how about you ask a facebook blog about it. It is "the garden professors" on facebook.

[url]https://www.facebook.com/groups/GardenProfessors/?hc_ref=NEWSFEED[/url]

They will dig up only science based - peer reviewed papers and give their reply. I don't want to take your idea and post there because I'm sure I'd get something wrong in my way of saying what you already understand. I love asking them for their help because you get science not myths.

z

Please feel free to ask them if injections of bt into the squash stem are effective. I am not a big Facebook user.

There are lots of reliable postings online that say it does work. Here is one of them, but there are many more and I have seen firsthand that it does work in my garden. bt kills caterpillars and larvae so it is natural to assume that coating the interior stem tissue with bt will kill the SVB larvae that are eating it. I have also heard that spinosad injections will work but I have not tried them.

[URL]http://articles.extension.org/pages/65684/biology-and-management-of-squash-vine-borer-in-organic-farming-systems[/URL]

Here is an excerpt if you do not want to read the entire thing.

[B]Stem injections of [I]Bacillus thuringiensis[/I] (Bt) are frequently recommended for squash vine borer management, especially for organic gardeners. Trials in South Carolina compared spray application and stem injection of commercial formulations of Bt with a conventional insecticide and an untreated control (Canhilal and Carner, 2007). The injection and spray application methods produced similar results, and the Bt treatments provided control similar to that of the conventional insecticide.
[/B]
I am an organic gardener so I prefer this to application of conventional pesticides. Since the results are similar, why add pesticides to your plants?

I have been keeping them off my plants for years with a rather simple technique. I use a small bulb duster and dust the lower stem with a good coating of Sevin up to where the blossoms are. I do not dust blossoms or anything above open blossom area and have had no problem with SVB starting higher up the plant but I don't doubt they can. Every time there is a heavy rain and the Seving is washed off I just walk down the row and dust the stems of course as the season goes along the dusting has to go further up each time. I eventually get sick of squash and just let them go or pull them up but I haven't last any plants to SVBs in years using this technique. The only problem would be a long rainy spell but that hasn't happened so bad that I couldn't keep the Sevin on them but I could see it happening and if it does I might try the BT injections.

Bill

I get hit with SVB every year, but have yet to loose a zucchini plant to them. I only grow two that are both bush varieties (vs vining), so only one very short main stem.

The minute I see SVB frass, I go digging into the stem with a pair of sharp pointed garden scissors until I find them and then chop them up. It's amazing how healthy and productive the plants are even after I've hacked the heck out of the stem to the point where it's barely half attached!

This year I have eight plants and only two have been attacked and both are still producing.

I do not use chemical insecticides but I thought that once a week dusting sounded like a lot of Sevin to apply so I looked up the Sevin label and for squash it says that the maximum number of applications is 6.