Potato leafhopper above threshold

This information was summarized from a June 28 teleconference with ISU extension field specialists in crops.

  • Scattered rain fell during the past week and ranged from none to 2 inches. Crops are growing rapidly. In a few areas that did not receive rain, moisture stress is beginning to show. Observations of potassium deficiency continue. These symptoms occurred most often in areas of fields with compacted soils, shallow-planted crops, or in no-till fields.
  • Most of the replanting of corn and soybean is complete. Because replanted corn plants are small, some pests such as black cutworm are still a problem according to Mike White (south central).
  • Weed control is improving in most areas, as postemergence herbicide applications and cultivation are progressing. The field specialists continue to receive crop injury calls related to drift. See the herbicide drift reduction article in the June 21 ICM newsletter.
  • European corn borer larvae have hatched, but little damage has been reported so far. Scouting will continue this week.
  • Antracnose leaf blight in corn was reported by Brian Lang (northeast), Virgil Schmitt (east central), Jim Jensen (southeast), and Mark Carlton and Mike White (south central). This leaf disease seems to occur in fields that had earlier root rot problems and in 2nd- or 3rd-year corn.
  • Potato leafhopper problems in alfalfa have worsened statewide. Some fields that are above the economic threshold for this pest are being sprayed, but others are being ignored. Many of these fields are several times above the threshold. See the article by Marlin Rice and colleagues potato in last week's ICM newsletter. Second cutting hay harvest continues in most areas.
  • Leaf diseases in some second cutting alfalfa fields may cut the yields in half according to Brian Lang (northeast).
  • Oats and wheat are maturing and starting to change color. Jim Jensen (southeast) reported that wheat harvest will begin soon.

This article originally appeared on page 131 of the IC-482(17) -- July 5, 1999 issue.

Updated 07/04/1999 - 1:00pm