I am growing hops for the first time this year. I planted 3 Chinooks and 3 Willamettes this past spring. The Willamettes are growing really well but have not flowered. The Chinooks are flowering and I may have enough for a couple of batches this fall. My question is, when I went to water them today I noticed several caterpillars on the bines. But, only on the Chinooks. Nothing was on the Willametts. They are 1-1.5" long, and somewhat colorful with spines sticking up. What are they? Are they harmful? What do I do about them? I live in the Kansas City area, if that helps. Steve