More rain; wireworms and white grubs reported

This information was summarized from a May 14 teleconference with ISU extension field specialists in crops.

  • Up to 5.5 inches of rainfall was reported during the past week, which slowed or halted corn and soybean planting. The most progress was made in northeastern Iowa where 1-3 days of fieldwork was reported. Crop specialists commented that planting varies widely within counties, depending on the amount of rainfall. Estimates by percentage of corn and soybean planted were discussed (see table).
  • Established alfalfa is approaching bud- to mid-bud stage. Hail caused damage to alfalfa in some areas, whereas damage to corn and soybean was minimal.
  • Soil crusting was reported in areas of heavy rainfall (see article in May 7, 2001, ICM newsletter, pages 62-63, for information on dealing with soil crusting).
  • Wireworm and white grub problems were reported in southern and west central Iowa. Several fields may need to be replanted.
  • There were scattered reports of black cutworm in corn above the treatment threshold. Dingy cutworms were causing minor leaf feeding in corn.
  • Bean leaf beetles are out, but no damage was reported.

Estimates by percentage of corn and soybean planted:

Area Corn (%) Soybean (%)
Northwest 70 5
North central 70 20
Northeast 60 25
West central 85 15
Central 90 30
South central 70 25
Southeast 75 35
East 95 25
Southwest 90 25

This article originally appeared on page 83 of the IC-486(10) -- May 21, 2001 issue.

Updated 05/20/2001 - 1:00pm