Oregon Pest Identification

The Japanese beetle is just one of many pests that affect Oregon's forests and gardens each year.

To a great extent, Oregon is characterized by its agriculture, horticulture and magnificent forests. Every year that state's farmers, turf experts, gardeners and forestry personnel work diligently to identify the myriads of insect pests. If allowed to gain a foothold, they are capable of doing serious damage to forests and crops alike. Some of these pests belong to invasive species, thereby making their identification of even greater importance.

Threat to Hazelnuts

Approximately 30,000 acres of Oregon's Willamette Valley are dedicated to hazelnut production. Additionally, the region's forests are home to wild hazelnut species. Insect pests that pose a threat to both wild and cultivated hazelnuts include filbertworms, filbert weevils, filbert aphids and hazelnut aphids. The larvae of filbertworms and filbert weevils cause extensive damage by feeding on nut kernels. Aphids feed on both husks and leaves, thereby draining essential nutrients from the latter.

Cereal Leaf Beetle

These insects are identified by their blue-green wing covers, red legs and area of red behind the head. The larvae measure approximately 3/16 to 1/4 inch in length and are identified by their lemon-yellow hue. Both adults and larvae feed on the leaves of winter wheat and spring grains. Although damage to winter crops is usually minimal, these pests cause area farmers to suffer large reductions in oat and barley yields.

Japanese Beetles

Japanese beetles are invasive pests that are identified by their metallic green and copper colored wing covers. These insects lay their eggs in the soil, which upon developing into the larvae stage, feed on the roots of grass in pastures, golf courses and lawns. Larvae also attack the roots of corn, strawberries and tomatoes. Adults feed on the leaves of woody and herbaceous plants, shade trees, roses, corn and a number of other crops.

Mound-building Ants

Harvester and thatch ants are two aggressive insect types that build mounds and feed on vegetable plants. Of greater concern is the growing presence of imported fire ants, which now reside in 11 California counties, according to the Oregon Department of Agriculture. Mound-building fire ants not only cause crop damage, but are more aggressive than their mound-building cousins and are capable of inflicting severe stings, which sometimes require medical attention.

Other Pests

Oregon gardeners are familiar with other types of common pests, which attack their crops in a variety of ways. Some of these nuisances include green aphids, cabbage worms, cucumber beetles, cutworms and flea beetles. Cutworms, for example, kill vegetation by chewing off seedlings at the soil line, feeding on leaves and eating holes in rooting systems. Officials at Oregon State University generally encourage gardeners to use natural means of pest control before turning to pesticides.

References

• Oregon State University: Identification of Invasive and Reemerging Pests on Hazelnuts
• Oregon Department of Agriculture: Cereal Leaf Beetle
• Oregon Department of Agriculture: Japanese Beetle
• Oregon Department of Agriculture: Imported Fire Ant
• Oregon State University: Growing Your Own