Scutigerella immaculata
Pest description and crop damage Active, white, fragile, centipede-like arthropod soilborne relatives of insects, 0.25 inch long, with 12 or more pairs of legs. This pest moves vertically in the soil and will cause root damage to new steckling and seedlings once temperatures reach 45 degrees Fahrenheit. They damage sugar beet primarily early in the season by feeding on germinating seed or on small root hairs of steckling beets. Symphylans are in unpredictably spotty infestations and can be scouted for by placing potato baits throughout field to identify hot spots. Treatment may be necessary as in-furrow incorporation in fields with a history of symphylan issues prior to planting seed or steckling transplant.
Management-chemical control
No formal economic thresholds exist for insecticide treatment decisions. No effective "rescue" treatments for symphylans can be applied postemergence in sugar beet seed fields. Only ethoprop, labelled for at-plant application, is registered.