That’s my thought too, except the plants don’t die off quickly, they just “stop” suddenly (from just prior great growth and flowering), and then very slowly (usually) die off from the stem up. If it’s as though the pathogen / parasite / insect doesn’t quite completely destroy the stem, in order to maintain its “housing” until it’s ready to pupate or reproduce, and and “some” nutrients and water get through.
Also see my post above, # 701.
In the future, if I have will to try again, and assuming it is borers, is there anything that wards off the adults laying the eggs? We’ve had so many rains that pesticide would likely just wash off. Some sort of natural repellent plant planted around the squash / melons / cukes?
I know there are products that trees and shrubs can take up to help prevent or kill off borers, but I don’t know about their compatibility with squash, etc., and, they are NOT recommended for veggies (residue in the fruits, etc., I would guess.)
Thanks!
“...is there anything that wards off the adults laying the eggs?”
It’s a fly if some kind that lays her eggs there, so your best defense is a row cover until that phase of that particular fly is over. Same works for anything in the Cruciferous family too, such as broccoli, cabbage, cauliflower, etc. They have the white/yellow Cabbage Moth that uses those plants as a host for their eggs. Hence, the green worms you sometimes have in broccoli. Ick!
You’ll have to see what the life cycle of that bug is, in your growing zone. The culprit is at the other link I sent you. It was an orange-backed fly of some sort. There were other ideas for prevention of Squash Borer there, too.