GRASSHOPPERS, CRICKETS, CICADAS & KATYDIDS

Order Orthoptera

Crickets, grasshoppers, katydids and locusts as a group of insects can be easily distinguished by strongly defined chewing mouthparts and enlarged hind-legs that have been designed for hopping or jumping.

There are few places throughout Australia where the noise of crickets and grasshoppers is not one of the background choruses of spring and summer nights. Many species in this order can sing by stridulation. For most species rubbing modified portions of the forewings together produces sound. The sound is a “love-‘song” produced by the male to attract a mate.

Crickets are usually nocturnal, though cicadas are more likely to be found during daylight hours. The tree cricket is a predatory insect, others like the mole cricket feed on roots and burrow in the soil.

Grasshoppers can be both nocturnal and active during daylight hours, and are divided into short and long horned groups, with the ‘horns’ referring to the length of antennae. The long-horned grasshoppers have antennae longer than the body. Long-horned grasshoppers are the larger variety, and are almost all plant eaters and very often nocturnal. Most grasshoppers have two pairs of wings Grasshoppers have five compound eyes and can see to the front, to the side, and to the back.

Short-horned grasshoppers, including the locusts, are active during the day. The name locust is given to species that can occur in swarms. This includes the Australian plague locust, which has a black patch at the tip of the hind-wing and some scarlet on the hind-legs.

Most grasshoppers eat plants, but some long-horned grasshoppers also eat dead animals or catch and eat other insects, Grasshopper eggs are mainly laid in the soil, although some do lay eggs on leaves. The eggs lay dormant until it rains, sometimes for years. Once hatched, if conditions are right, the next generation can be produced within a month. Juvenile grasshoppers do not have wings, but develop into adults within 40 to 60 days.

BIOLOGICAL CONTROLS

Beetles, birds, lizards, mice, snakes, and spiders all prey on grasshoppers and are part of nature’s version of green pest control. Birds are possibly the most important natural enemy of this order, particularly the ibis. On the domestic front, chickens relish hoppers and will consume an amazing amount. Almost all larger native birds will grab a grasshopper or cicada when opportunity knocks, including Magpies, Currawongs Kookaburras, and of course Emus.

PHYSICAL AND CULTURAL CONTROLS

Early morning forays into the garden while hoppers are sluggish will result in good hand collected yields. Nets could be used, but not too many would care to be spotted flitting around shortly after dawn with a butterfly net in hand.

Cultivating the soil and leaving autumn and spring and leaving it exposed for a couple of weeks will make finding the recently laid eggs a deal easier for natural predators.

Grasshoppers seem to find the colour yellow irresistible. This can be exploited by using yellow sticky boards and other traps rap grasshoppers.

LEAST TOXIC CHEMICAL CONTROLS

As mentioned elsewhere in our Green web pages Canola oil is known to be a strong grasshopper attractant, and can be utilised to make any grasshopper baits more attractive.

See our Natural Pest Control pages for Chilli and garlic sprays, they are not likely to kill the hoppers, but will make a useful repellent.

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