Florida Gardening: green caterpillar, 3 by jaylunsford

jaylunsford wrote:
First off, I am a noob gardener, I live on the water up in Navarre, FL and all of my gardening takes place in cedar containers or raised metal beds.
I recently (couple weeks ago) transplanted some new zucchini squash into a cedar plantar, and I am now seeing these small green caterpillars in the soil and attached to the back of some of the leaves. Can anyone tell me what they are from the pics?
Are these worrisome? If so, what do I do to get rid of them.
Also, I have these small, what appear to be white mushrooms now popping up in the same bed. I have not had any problems with any of my other planters yet, so wnated to get some advice. Thanks in advance.