Q: On my yellow squash leaves there are several rows of very tiny, copper-colored, jewel-like, round things. What are they?
A: They’re squash bug eggs. Unless you want to lose your squash crop, kill ’em now!
The eggs will quickly hatch into tiny squash bugs. Adult squash bugs are a bit more than a half-inch long and a quarter-inch wide. They are dark brown, sometimes mottled with gray or light brown, flat-backed, and they stink when crushed. Both nymph and adult squash bugs suck sap from leaves and stems, simultaneously injecting a toxic substance that causes stem wilt.
You can mash the eggs with a gloved hand to control them organically. As you’ve noticed, they are easy to see. Examine all of the leaves closely.
Carbaryl (click for sources) works very well. Spray as needed but do it in late evening to protect honeybees..
see Squash Bugs
For an organic option, Chris French from Georgia’s Finest Organic Farm in Waverly Hall, GA says “After a few years of losing too much of our squash crop, here is what is most effective for me. First, I am at the farm at daybreak and check all the blooms and lower stems for signs of spotted or stripped cucumber beetles,squash bugs,vine borers etc. Squash bugs love to hide in my over mulched areas and under my plastic on the raised beds. As I find an outbreak I first pull all damaged or dead plants out of the field. I use M-Pede ( insecticidal soap) and Surround WP with Dipel. Also, a sticking agent can be used. A sticking agent is OMRI approved to bind the additives to the plant. Xr-70 is a commercial variety, but there are many others.
Now the rest is just hard work. I spray and target the bugs with the mix. This will not kill them, but it will stop them from being so mobile. I then bring in my crew and we pick all of them if we can. I rotate about 5 Acres so this can be a lot of work. Also remember early and often is the best method.”