Please read this - it's important!

There back! Cucumber beetles like the one in this picture. They are damaging, nasty, horrid little things. Getting rid of them is an all-hands-on deck proposal - please check cukes and squash frequently. If they are driven from one plot, they'll just move to the next.

The beetles damage things badly, leaving scars, like the leaves above. 

Using Neem Oil, [organic], hot pepper spray, planting pungent varieties of marigold [French of Mexican] can help. However, the most efficient way to get rid of them is to squash them by hand and clear the eggs off the underside of cuke and squash leaves. The eggs look like the picture above. Don't just scrape them off - scrape them off into a bottle of water and dish soap. They'll still hatch if they are on the ground. It can take some time to get rid of them, but persistence pays off.