Idaho                              Aphid                                                        Flyer

English Grain Aphids

    On the whole the aphid counts are still low. Cereal aphids seem to have taken flight with all the maturing crops. We are seeing a few more English grain aphids in the northern part of the state last week. These counts seem to reflect the maturing grain in the area. The economic thresholds for English grain aphids are 2 per tiller at flowering, 8 per tiller at water stage, and 10 per tiller at milk stage. As with Russian wheat aphid, treatment is probably beneficial after the soft dough stage.

The Asian multi-colored ladybug entering northern Idaho

    Harmonia axyridis, the Asian multi-colored ladybug, was found in Boise during 1994 and has been spreading eastward across southern Idaho for six years now. During June 2000 this species was found in Pullman, Washington. Residents of northern Idaho can anticipate finding this species in their deciduous trees within a few years. If the pattern seen in Boise holds in the north, H. axyridis may prove to be a beneficial addition to our ladybug fauna by controlling tree-dwelling aphids that produce honeydew and cause shaded picnic tables, etc., to become sticky and unpleasant. Watch where you park your cars!

Cereal aphids

    Russian wheat aphids have picked up in Parma, Rockland, and Burley. This is a sign that the wheat in these areas is maturing.  Any late planted grain needs to be surveyed for increasing populations.

                      Funded by the University of Idaho Agricultural Experiment Stations and the Wheat & Barley Commissions.

Samples collected JULY 7, 2000