Small Grains Small Grain Insect and Disease Pest Management

lowing IPM procedures for managing grain aphids. Results Ninety-four percent of the 39 field tests comparing preventive versus IPM practices showed that IPM practices were more profitable. Few fields developed threshold aphid populations so insecticide was not applied and yields were not affected. Money was saved and total pesticide usage was reduced. Surveys of untreated fields over the last two growing seasons have shown that an average of only 4% of fields actually develop economic aphid populations. The fields that do develop problems are invariably planted early (mid-October or before) and are usually barley. This information has been extended to farmers in meeting, field tour, teleconference and publication formats. To date, several farmers, some being the most progressive and influential, have adopted IPM practices on their farms and are pleased with the results. Survey of Grain Aphid Infestations A survey was conducted in the 1991-1992 small grain growing season to determine the percentage of fields that developed threshold levels of aphid infestations. Ninety fields, that did not receive preplant insecticide treatment, in 24 counties were scouted for aphids in early December, late January and again in late February. Scouting at different times allowed us to see how aphid populations changed over time. Fields were scouted by going to several areas in each field and determining the number of live aphids per foot of row. Planting dates were also recorded for each field, as well as other information, such as variety and fertility practices, that may have had an impact on aphid populations.