Garden Insects: Grasshoppers

Identification

There are several hundred species of grasshoppers, but only a handful that cause damage to crops and ornamental plants. Many common garden species are 1-2 inches in length and gray, green or brown in color. All grasshoppers have large eyes and large hind legs specially developed for jumping. Adult females dig holes in the soil with their abdomen and lay eggs. One year later, wingless nymphs hatch in the spring. By summer, they have developed into mature winged adults.

Favorite Plants

Some species of grasshoppers are general herbivores and feed only on grass. Others feed on just about any type of wild or cultivated plant available, including the leaves and flowers of plants. One interesting aspect of grasshoppers is that some of the vegetations they eat contain

Chemical

s that are either toxic or taste bad. These

Chemical

s are absorbed into their systems and used as a means of repelling would be predators

Damage

Grasshopper Damage occurs most frequently during dry summers. The potential for Damage increases as the summer progresses and crops start to develop fruit. Adults will be more likely to move into yards and gardens in July and August. Adults can quickly shred plants and either destroy or severely reduce potential yields.

Organic Methods of Control:

Cultural or Mechanical

• Cover seedlings with row covers and valuable plants with metal screens.

• Leave an unmowed grass border around the yard or garden to delay grasshopper movement toward crops and ornamentals.

• Fall plowing can help destroy some eggs.

• Plant a "trap" crop like zinnias around the edge of the garden to attract and hold grasshoppers.

Biological

• Attract grasshopper predators to the garden like birds, lizards, praying mantis, rodents and spiders.

• Apply the beneficial protozoan Nosema locustae to the yard and garden if you live in an area plagued by grasshoppers. This attacks grasshoppers in the nymph stage and may take up to one year to see the full effects.

Chemical

• Spray an insecticidal soap directly on the grasshoppers.