Description

The order Orthoptera includes crickets and katydids, which can be treated the same in organic gardening. Their most defining feature is their very strong hind legs which make it possible for them to jump away. They are usually green, brown or grey in colour. The nymphs are miniature versions of the adults, but wingless. They live on the ground usually in burrows in the soil or in crevices in logs and under leaf litter.

Adult size: 10 mm- 15 cm

Out and about

During the warmer months. There are many thousands of species worldwide occupying virtually every type of habitat except very cold regions.

Reproduction and Life cycle

The life cycle of grasshoppers consists of three stages: egg, nymph and adult. The female lays up to 150 eggs in clusters protected in a pod made of secretions that she produces, in or on the soil during summer or autumn where they stay until the next spring. The nymphs go through 5 stages, becoming more like the adult with each moult, over five to six weeks. The life cycle is about two months from egg to adult.

To deter

- Keeping weeds down and not allowing grass to grow will discourage the female from laying eggs - Grasshoppers do not like to lay their eggs in tilled ground, so they may not be so prevalent in cultivated areas

To control

They are much slower in the morning and evening which makes it possible to catch or cover them with a spray. Flour spray -Make up a runny mix of flour and water and spray on the on the grasshoppers if you can or smear over the leaves of the plants they are targeting. They will get covered and slow down enabling them to be caught, especially by birds. Water trap-Bury a yellow bucket in the ground up to its rim. Fill with water and add 10% molasses. Canola oil can be added as an attractant, which will also create a film that will deter bees. - Grasshoppers are attracted to yellow, so try commercial sticky strip traps - Neem spray may be effective on small grasshoppers - Pyrethrum spray as a knockdown - Chilli and garlic spray as a deterrent - Diatomeous earth may also be effective on young nymphs as they have an exoskeleton which they shed as they moult through the growing stages. They are wingless in these early stages.

Plants to repel

Plants to attract

Predators

Birds / Hoverflies / Robber fly / Praying mantis / Assassin bug / Parasitoid wasp / Paper wasp / Tachinid flies There are also predatory grasshoppers. A tree cricket (Paragryllacris combusta) has spiny front legs that they use to capture their prey. A katydid (Chlorobalius leucoviridis) which imitates 20 odd cricket species in order to lure them.

Why they are a Pest

Grasshoppers, crickets, katydids and locusts are all leaf chewers. In some species they can reach plague numbers, forming swarms and decimating entire crops. They are known as locusts when this happens. Grasshoppers are a major food source for other insects and birds.