Summer singers

In August’s heat and humidity, my gardening activity is down to watering my container plants and occasionally deadheading. 

Growing vegetables on the deck

For someone choosing flowers to accommodate bugs, I don’t know enough about the insects, their lives and habits. This seems like a good time to learn about a few. I started with the singers of the late summer chorus that fills the air from this month into fall. 

    I learned that most of what we’re hearing is crickets, katydids, and cicadas. I picture a cricket as a chunky black insect shaped like a grasshopper. Those are the field crickets. 

Field cricket, genus Gryllus

In addition to their chirps, the background trill or hum we’re hearing at night comes from tree crickets, which look quite different.

Snowy tree cricket, Oecanthus fultoni

    As you might guess, it’s the male crickets that make the noise. They have three kinds of songs, a loud one for attracting females, a softer one for wooing a potential mate once she’s nearby, and an aggressive one for warning off other males. 

     Crickets and katydids make their sounds not with their mouths but with their wings in a process called stridulation. They rub one wing across a rough patch on the other, similar to running a finger down the teeth of a comb. The shape of the wings amplifies the sound. Females are looking for larger mates, and the male crickets can improve their chances by moving their wings faster, which makes them sound larger.

    It’s true you can gauge the temperature by timing chirps of the snowy tree cricket. The number of chirps counted in 14 seconds plus 40 equals the ambient temperature. I find it sad to hear slowing chirps in late fall as the last crickets get too cold to sing.

    Katydids get their common name from their song, which some listeners think sounds like “Katy did, Katy didn’t.” They make a buzz, “zip” or “zeep” sound. They look like large green grasshoppers with long antennae. They have ears at the joints of their long front legs.

Common true katydid, Pterophylla camellifolia-photo Lang Elliott

     

     Crickets and katydids don’t harm our plants. They eat small bits of plant material without doing noticeable damage. They may function as beneficials, eating insect eggs, larvae, or small insects such as aphids or scale insects (I’ll be glad to share as many of those as they want!).

    The most dramatic of the singing insect trio is the cicada, which makes a distinctive crescendo “zee-oo-zee-oo” lasting 15 to 30 seconds. These songs can be as loud as 120 decibels, painful for human ears. The males sing for mates by puffing out their abdomens and bending flexible ribs on parts called tymbals. Adults suck sap from woody plants, but without doing much harm.

Annual cicada, Neogtibecen linne

    This is the insect that drops its nymphs to the ground, where they burrow under and feed on root sap. Annual cicadas emerge the next spring. Periodic cicadas emerge together on 13- or 17-year cycles.

17-year cicada, genus Magicicada

    These interesting insects add to the late summer ambience without doing anything gardeners need to worry about. Nice to know.