Dry Beans XIII-1

Symphylans

Gary L. Hein & Frank B. Peairs

Symphylan infestations are seldom seen in the region, and rarely require specific management actions.

Identification (and life cycle/seasonal history)

Symphylans are fast moving soil insects that resemble centipedes.  They grow up to 3/8 inch long, have long antennae and can have up to 12 pairs of legs.  They spend their whole life in the soil and move up and down depending on soil moisture and temperature.        

Plant Response and Damage

Symphylans feed on decaying vegetation and small root hairs on the plant.  They can severely prune roots and cause dramatic stunting and leaf distortion.  Root damage and resulting leaf distortion may resemble herbicide injury.  Damage usually is very spotty in fields, but it can be very noticeable. 

Management Approaches

Serious symphylan infestations are uncommon, but where they occur they are usually associated with high organic matter or heavily manured situations.  Deep vigorous tillage may reduce symphylan numbers.  Severe infestation may require a planting-time insecticide for partial control, but adequate control would likely require soil fumigation, a cost prohibitive alternative.

Categories: Dry beans, Insects, Symphylans

Date: 04/24/2006