It seems unlikely to be SVBs if you've used Sevin. Are you seeing any pale gray insects crawling on your vines and leaves? Are there any tiny reddish-brown egg clusters on the undersides of your leaves? I'm wondering whether you have squash bugs. They will cause a similar pattern of die-off.

On the other hand, maybe the SVBs have become resistant to Sevin. Look at the base of the plant; if you see an area where they might have entered, with some plant material exuding from it, that's what you've got.

I've heard sevin does not work on squash bugs once they are bigger and I've never heard either that seven prevented squash vine borers because they are in the stem of the plant. You might try making a liquid of it and injecting in your stems, but there are people on this board who have said sevin didn't work.

Look for frass at the base of your stems where they could have dug in. Your mulch is working with you, it's flat and they can't build nests underneath it.

Good luck!

I don't think that sevin does anything for SVB, tho it will kill most other insects, including the pollinators.

The only way I know to make sure (find out) what the cause is - is to look or cut open the stems near the soil. Look for frass and/or the borer in the stem. The SVB stops any nutrients from getting 'up' to the rest of the plant.

After further inspection, I didn't find any frass or cut open stems. I did however find a bunch of red/brown eggs and a bunch of small silver/grey bugs.

From riverfarm's post, it looks like I may have squash bugs. Is there a way to defeat these little beasts?

Thanks!

Pyrethrum is supposed to kill them, lye glycerine soap will soften their outside armor, then pyrethrum is supposed to sink in and kill them, a double whammy. I tried bt this year, did nothing, so I'm planting pyrethrum daisies next years, the early bloomer is a pink daisy called pyrthrum plant, the late bloomers are painted daisies and shasta daisies. Painted daisies is the professional flower to collect the pyrethrum oil.

You can attempt an organic way to get rid of them through interplanting them with squash plants, not sure if it works yet, or you can buy the oil on the internet.

The squash bug eggs will be (orangeish) in groups under the leaves. The SVB eggs will be the very same color but (5-6) singles and located along the stem.

You really need to slice open the main stem of the dead plant to find the SVB larvae.

So how do commercial pumpkin growers deal the Squash Bug? It would be impossible for them to search every plant for eggs. There's a pumpkin patch near me approximately the size of Rhode Island, how do they do it?

If the pumpkins are for jack-o-lanterns, not eating, then you could use a systemic insecticide.

Squash bugs prefer yellow summer squash, pumpkin, and winter squash to other cucurbits. You could plant a trap crop of one of those early in the season, treat it with a systemic pesticide, then plant your main crop a little later - just don't eat the product of the trap crop. Then when the bugs come out of dormancy in the spring, the majority of them will find the trap crop because it's larger and tastier, and the systemic pesticide will kill them. You could cover your other cucurbit seedlings with tule covers to help steer the bugs to the trap crop too.

Bayer Advanced (admire, guacho) is a systemic pesticide that stays active for several months and has been used effectively in this manner. It will kill bees too, so I'd suggest stripping flower buds from the trap plants.