Squash Vine Borer
Just a few days earlier, this squash vine looked healthy and fine. What happened? it was attacked by the larva of a moth. She laid her egg at the base of the plant.
The culprit ...
The name of this little pest that was caught chewing up our squash is Squash Vine Borer (Melittia Cucurbitae). It is the larvae of the Sesiid Moth which looks more like a wasp or hornet rather than a moth. The symptom of this pest attacking your plants is that the perfectly healthy vine suddenly starts to wilt.
What she does ...
The moth lays her eggs at the base of the plant and the caterpillars feed on the plant until ready to pupate. The problem is once the caterpillars are inside the plant Pesticides (organic or inorganic) are pretty much ineffective. It's almost easier to capture and kill the moth before it lays eggs. Try hanging yellow sticky paper (fly paper) around the plants to attract and kill them. You can get it at most greenhouse supply places and specialty shops.
In 2008, when the above information was gathered, was the first year that our sharing plot - #19 was planted with the "Three Sisters". in 2011 we again planted the "Three Sisters" and again several of the squash vines were attacked. this time around, we noticed and recognized the signs right away.
What else ...
The base of the vines had a discoloured -brownish appearance, and was mush to the touch. we evicted several of these intruders, and put Diatomaceous earth (organic pesticide) on the base of these plants. It seems that this year, the moths went one step further, and laid eggs into the squash themselves.