Wondering where all the noise comes from? Vernal pools. This is what they look like – ponds of stable water in the woods. This one is right next to a park hiking path. The occasional rings on the surface of the water are frogs, perhaps wood frogs. The tweeting sounds are spring peepers. Those sounds will be joined soon by calls of the upland chorus frog, which sound like running your finger over the tines of a comb. | Fairfax County Park Authority