|What is the Katydid doing?|
Just take, for example, the questions evoked by finding the above insect on your 'Prairie Harvest' rose, as I did recently. The knowledgeable gardeners among you may identify it as some sort of Katydid, or, if you're from the British Isles, a Bushcricket. But is it friend or foe? Predator or flower glutton? If I leave it there, on the rose, will it consume the rose and then make lots of little katydids to devour the rest of my roses? Alternatively, if I leave it there, on the rose, will it reward me by consuming the first scouts of the Japanese Beetles that I expect will reach my garden shortly? From my contacts with Katydids in childhood, I think they're harmless to myself and perhaps to plants, but I simply don't know enough.
And quick simple research, it seems, even in these days of instant information, isn't enough to do anything more than cloud the issue. To answer the question I've posed, I think one would need to be an entomologist with a lifetime spent specifically in research regarding this insect family. Even then there might not be a definitive answer. Katydids are in the family Tettigoniidae, which contains more than 6400 species. They are closely related to crickets, and the diet of some of them includes leaves, flowers, bark and seeds, but many speces are exclusively predatory on insects or snails. Some are considered pests by commercial crop growers according to one source, but that source doesn't mention which crops are affected. You can find lots of information about the wierd oral sex practices of the Katydids, but there is little written about their effects on garden plants. Is this yet another example of human voyeurism distracting us from the real issues at hand? It does me little good, and only leaves me feeling inadequate, to know that the Tuberous Bushcricket (Platycleis affinis) has the largest testicles in proportion to body mass (14%) of any recorded animal.
Which leaves me with what to do about my little friend here? I don't know. If it was on another rose than my beloved 'Prairie Harvest', for instance if it was on 'Sally Holmes' or perhaps on 'Knockout', I might worry about it less. I suppose as long as I find only one or two Katydids, I'll turn the other flower bud and allow them a chance to prove themselves. A few thousand Katydids would, however, overwhelm my good nature in the way that one Hun is seen as an interesting visitor, while a few thousand Huns is a marauding horde. Perhaps alongside that thought lies the answer; a properly maintained organic garden should display a balance: a little of this, and a little of that, but never too many of a hungry-looking contingent of Huns.