Corn rootworm hatch risks will continue to expand to the north throughout the week and into next weekend as accumulated growing degree days increase and reach/exceed threshold levels for initial or higher percentage hatching rates. Very warm to hot temperatures anticipated for at least the first half or so of this week across a good portion of the corn-growing region will also allow these accumulated heat units to increase at a more rapid rate. Initially, the primary hatch risk lies along/south of I-80 from Nebraska into Iowa and Illinois and then on east into the southern Great Lakes. By late week and into next weekend, however, initial or scattered hatches may occur as far north as eastern/southeastern South Dakota, southern Minnesota, Wisconsin, and into additional areas of lower Michigan and also southern Ontario, Canada. High risks will remain confined to the I-80 corridor and south, primarily, but some isolated more widespread hatches may occur in favored areas to the north of I-80, as well. Growers in the High risk area are especially encouraged to dig up roots and assess any local larvae populations and take any necessary actions.