In 2001 Erratic weather patterns in 2000 make root maggot population predictions for 2001 somewhat difficult. In general root maggot populations were lower in all Minnesota counties in 2000. In North Dakota root maggot populations were lower south of Grand Forks. Adult fly survey counts by American Crystal Sugar Company agriculturists and NDSU scientists determined numbers to be moderate in southern Walsh County and along the Red River in Pembina and Walsh counties. Fly counts in northern Walsh County and Pembina County were at near all time record high levels in some townships, figure 1.
Early planting promotes large root systems that better tolerate insect damage.
Rotary hoe or harrowing before eggs hatch reduces survival. Oat cover crop may reduce populations. High label rates of insecticides are not needed in low and moderate SBRM population areas, table 1. On the next screen you will see a map window with some selection steps to the left of the map. The first step is to select a crop year by clicking on the year you would like.