Name: Sipha maydis
Alias: Hedgehog grain aphid is a relatively new pest to North America. From a distance it looks similar in size and shape to the pear-shaped body of a green pea aphid except it is dark-brown. On closer inspection it has hairs covering its back, giving it the “hedgehog” appearance. Females overwinter and give birth to its “clones” in the spring.
Crimes: Hedgehog grain aphids tend to feed on grain crops such as barley and wheat. This damages the plant and can cause stress and a reduction in yield. Their far more serious crime is the fact that they can transfer diseases such as the barley yellow dwarf virus.
Redeeming Qualities: None known.
Sentence: While more research is still required, it is usually accepted that the hedgehog grain aphid is susceptible to the same control methods we see with any aphid species. Biological controls such as lady beetles and assassin bugs can keep populations in check. The threshold for control is probably smaller than it is for green aphids. If you see more than 20-30 aphids per stem then control is merited. Many insecticides are labeled for use in grains to control aphids, but many of them, such as Stallion or Cobalt Advanced, are also restricted use. Silvanto and imidacloprid are some that are not restricted use and can be used in chemigation. Make sure to always follow the label instructions.