Snowy Tree Cricket

The snowy tree cricket is a slender, pale-bodied cricket found across much of North America, well known among naturalists for its evenly spaced, rhythmic chirping song and its close relationship between chirp rate and ambient temperature. It is often called the "thermometer cricket" because counting the number of chirps in a set period and applying a simple formula gives a reasonably accurate estimate of the surrounding air temperature, a phenomenon first popularized in nineteenth-century natural history writing.

Unlike field crickets, which are dark and ground-dwelling, snowy tree crickets are pale, almost translucent green or whitish insects adapted to life among shrubs and tree foliage rather than on the ground. Their coloration provides excellent camouflage against leaves and bark, and their songs, produced primarily on warm summer and early fall evenings, are among the most familiar and soothing background sounds of the season across much of the continent.

• Slender, pale green to whitish-yellow body, appearing almost translucent.
• Long, thread-like antennae, much longer than the body, typical of true crickets.
• Long, membranous wings held flat over the back, used both for flight and for producing sound.
• Males have broader, more rounded forewings adapted for stridulation; females have narrower wings and a visible ovipositor.
• Small dark spots at the base of the antennae, a helpful identification feature in some related tree cricket species.
• Distinguished from other tree crickets primarily by call structure, which is even, rhythmic, and clock-like.

Snowy tree crickets are found across most of the United States and southern Canada, inhabiting shrubs, trees, tall weeds, and garden vegetation. They are most active and most often heard from mid to late summer into early fall, typically singing after dusk and continuing into the night.

Males produce their well-known song by rubbing specialized structures on the forewings together, a behavior called stridulation, to attract females and signal territory. The chirp rate increases with rising temperature and slows as it cools, a relationship precise enough to estimate temperature from counting chirps. Snowy tree crickets feed on soft plant tissue, small insects, and other organic material found on the shrubs and trees they inhabit, and their pale coloration helps them remain camouflaged among foliage during the day while they rest.

Females lay eggs in slits cut into plant stems or twigs during late summer and fall, and the eggs overwinter within the plant tissue. Nymphs hatch in late spring, resembling small wingless versions of adults, and develop through several instars of incomplete metamorphosis over the summer before maturing into winged, singing adults by mid to late summer. There is one generation per year across most of the range.