A. This is an aphid, specifically the potato aphid (Macrosiphum eupohorbiae); the winged form is shown in the photo on the left and immatures and wingless adults on the right. Like many aphids, this species can be either green or various shades of red and pink. While aphids as a group are present and abundant throughout most of the season, this species of aphid is most often found on potato in early spring right after crop emergence. It is controlled by plantingtime neonicotinoid insecticides, but for fields without such treatments this aphid can establish and potentially transmit virus.
B. This is the tuberworm; the adult male is pictured on the left (caught in a pheromone trap) and the mature larva on the right. Tuberworm is most important in the weeks immediately before harvest. This insect is present throughout the season, feeding on the foliage, but builds up to large populations late in the season when it invades the tubers and can cause major losses.
C. Here is the beet leafhopper; a close-up of the darker spring form is on the left, and a specimen on a potato leaf is pictured on the right. It is most important in the spring. This insect transmits the phytoplasma that causes purple top disease in the Columbia Basin, and plants infected early in the season are damaged much more severely than those infected later.
