Leg-Scraping Locusts Make Music, Tell Temperature This short-legged shield-backed katydid has to undergo one more molt before its wings will be developed. There is a grasshopper that has been frequenting our small front yard in recent days that brings back boyhood memories. Some grasshoppers are called locusts, a name generally given to species that is quite mysteriously capable of changing its habits, form, traveling in swarms and destroying valuable crops. The species we have been observing is the Carolina locust. I’m sure it’s the same one of our boyhood when, during summer vacation from school, not many days went by that we didn’t have a make-up ball game on some vacant lot where these insects appeared to always be on hand. The locust I speak of is a strong flier and, while in flight, its second pair of wings, that are black with a pale yellow border, make it surprisingly resemble a butterfly. This large insect produces a very fast purring or beating sound, then a fluttering or somewhat rattling noise made only when in flight. Naturally, with energy to burn some days, we’d chase them down, catch and finally squeeze them until they "spit tobacco juice" – tobacco juice my eye! Gosh did that stuff ever smell! Boys will be boys! The color of widespread Carolina locusts can range from gray to rusty-brown and will easily blend in with the dry fields and grasses of their habitat. They belong to the large order of insects, Orthoptera, and are characterized by membranous, folded hind wings covered by leathery narrow fore wings. Included in this order are locusts, cockroaches, katydids, cicadas, crickets and grasshoppers. All in this group have two pairs of wings. The Carolina locust’s fore wings are, true to the order, leathery, long and narrow and are not used for flying. Orthoptera means straight wings and refers to these rigid fore wings which provide the broad, membranous hind wings with protection. The Carolina locust’s colorful hind wings contain many radiating veins that allow the entire wing to be folded flat, fanlike, hidden beneath the fore wing when the insect is not in flight. Another locust we’ve been seeing occasionally is the red-legged locust. Its hind tibia, the upper leg containing the herringbone-like packets of muscles used for jumping, are bright red with black spines. It is quite an attractive insect that inhabits fields, vacant lots in cities and suburbs, and open woods. Its food consists of, for example, native grasses, introduced weeds, alfalfa and soybeans. Like other grasshoppers and locusts, the female red-legged locust thrusts several egg masses, each containing around 20 eggs, into the soft soil where they will overwinter. Nymphs, like miniature adult grasshoppers lacking wings and genitalia, appear in spring and, after several molts, finally develop wings and become adults by mid-summer. The similar Rocky Mountain grasshoppers reached plague proportions in the West before 1900 but now are probably extinct. The "Grasshopper Glacier" near Cooke, Montana, contains millions of embedded Rocky Mountain grasshoppers presumably from swarms that settled and froze on the glacier many years ago. Grasshoppers are divided into two groups. The long-horned (antennae) include, among others, the katydids, the greenish meadow grasshoppers and the cricket-like shield-backed grasshoppers that I’ve been occasionally seeing in our front yard. Long-horned grasshoppers are characterized by antennae longer than the body and by ears (tympana) set in the front legs. The males do their singing, or stridulating, by rubbing a scraper on the base of one front wing against a file-like ridge on the underside of the other front wing. A monument in Salt Lake City pays tribute to the flocks of California gulls that destroyed hordes of Mormon crickets, a species of long-horned grasshopper, that were eating the crops of the early Mormons. Those in the short-horned group, including the locusts, have antennae shorter than the body and their ears are situated in the abdominal wall. The males "sing" by rubbing a row of stubby comb-like teeth on the inside of the hind leg against a hardened edge on the front wing. Other members of the interesting Orthoptera order of insects, the crickets, have been fiddling around in the tree-tops on recent warm evenings. In fact the higher the temperature the more rapidly and higher in pitch the males "fiddle," considerably like the locusts. Their vibration frequency can range from 4900 to about 17,000 which is higher than most people can hear. One amazing cricket, the snowy tree cricket which also inhabits this region, is frequently referred to as the thermometer cricket and also the most beautiful of all insect singers. Its accuracy has been scientifically proven. Count the chirps in 15 seconds, add 40 and you should have the degrees of Fahrenheit temperature! How well we remember the day in the garden watching a female robin catch one grasshopper after another, presumably for her nestlings in a nearby spruce tree. Hooray for the vegetables, three cheers for the robin, and, well, tough luck you jumpers in the garden! This column appeared in the Door County Advocate on 08/30/2003. © Copyright 2003 Roy Lukes. All rights reserved.