The first days of summer were hot, humid and generally quiet in terms of weather. Scattered rain showers this week brought varying amounts of moisture to the state and the response by corn and alfalfa was immediate.

Field crops in the southern and west central districts have exhibited remarkable growth in recent days and waist-high fields are now relatively common in the south. Harvest of second crop hay is moving ahead due to favorable drying conditions, nearly all of the state’s corn acreage has emerged, and soybean planting is expected to be finished in a matter of days. Despite the recent rains, soil moisture levels are still not adequate in most parts of the state. The general consensus among Farm Reporters and county Ag Agents is that more precipitation is needed soon.

Weather conditions in the past week have been ideal for the development of many insects, the most noteworthy being the European corn borer and potato leafhoppers. Populations of potato leafhoppers have increased sharply in a week’s time and many alfalfa fields now support above-threshold numbers of leafhopper adults and nymphs. As June draws to an end, Wisconsin farmers should expect soybean aphid colonies to grown more rapidly, possible armyworm problems in corn and small grains, emergence of corn rootworm adults, and more pressure from the potato leafhopper.—Krista Hamilton

As a new feature we are providing an Forecast of Insect Migration into the Midwest (for Friday, June 23 to Monday, June 26). This forecast was developed and provided by Mike Sandstrom and Dave Changnon, Department of Geography, Northern Illinois University DeKalb, IL 60115<

DAY 2 (FRIDAY, JUNE 23 NOON THROUGH SATURDAY, JUNE 24 NOON):

Relative Risk of Insect migration into the Midwest: LOW (5-10%) – greatest risk area is mainly along and south of the Interstate 44/70 corridor in central/southern Missouri, southern Illinois, southern Indiana and Ohio, and Kentucky.

The cold front will continue to move south during the Day 2 period (Friday afternoon into Saturday morning) as high pressure continues to build into the upper Midwest. Showers and thunderstorms will once again form along and either side of the frontal boundary, especially along and south of I-70. Only a low risk of insect migration will be forecast for this area given feeble southerly winds to the south of the boundary in the lower levels of the atmosphere. Further north, high pressure will continue to build in especially along and north of I-80, bringing calm or light northerly winds and little to no risk of insect migration. An upper level weather disturbance may cause late day precipitation in the Dakotas and northwest Nebraska, but this appears to be of little concern to insect migration given unfavorable wind flow (non-southerly winds) into this area.

LONG-TERM (DAYS 3 TO DAY 5 – SATURDAY, JUNE 24 NOON THROUGH MONDAY, JUNE 26 NOON):

Relative Risk of Insect migration into the Midwest: VERY LOW (2-5%) – greatest risk area is mainly along and south of the Ohio River in Kentucky on Day 3, no risk of insect migration exists across the Midwest on Days 4 and 5.

The cold front will finally make an exit from the Midwest on Day 3 (Saturday into Sunday morning). Before it leaves the Midwest, scattered showers and thunderstorms may develop along its length as it continues to move southeast and weaken. Only a very low risk of insect migration is forecast for Kentucky on Day 3. Elsewhere, and on Days 4 and 5 across the entire Midwest, no risk of insect migration is forecast as calm or light northerly winds in association with a building high pressure continue to take hold across the Midwest. An upper level disturbance may bring scattered precipitation to parts of the Midwest this weekend into early next week, but little to no risk of insect migration is associated with this feature.

Follow these links for specific crop insect reports:

• CORN
• SOYBEANS
• FORAGES

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