Cuckoo Spit - Froghopper - Frog Hopper. On leaves or stems of plants 

Unsightly but not really a problem. That just about sums up Cuckoo spit or froghopper to give it it's proper name.

Hidden beneath the cocoon of 'spit' is a little young Froghopper - sucking away at the sap. Even if they are seen in large numbers, they rarely do enough damage to get worried about. Because of their protective cuckoo spit coating, they are difficult to treat with insecticides, and not really worth the bother. Simply wash them off with a jet of water!

Spittle bugs, froghoppers or Cuckoo Spit. Little damage but  unsightly - wash off, or if really desperate, spray with jet of Bifenthrin or Provado.

The cuckoo spit 'nest' together with the disturbed Froghopper. Sucks a bit of sap, but not a real problem.