Q: Some of my friends say the loud chorus of chirping sounds at night is tree frogs and others say it is cicadas. Do you know?
A: I think you were hearing annual cicadas and katydids singing in the treetops.. There are several cicadas in the genus Tibicen rasping away in the trees now.
You probably were hearing a mix of Tibicen pruinosus, Tibicen linnei, Tibicen tibicen and Tibicen canucularis. Both katydids and cicadas make sound by rapidly flexing or rubbing parts of their bodies.
Listen to them at
Cicada(scroll down to the Tibicen species)