Links to these articles are strongly encouraged. Articles may be republished without further permission if published as written and if credit is given to the author, Integrated Crop Management News, and Iowa State University Extension and Outreach. If articles are used in any other manner, permission from the author is required.
By Jon Tollefson, Department of Entomology
A user of the revised Economic Threshold that we recently published in the Integrated Crop Management News noticed that there was an incorrect function. I didn’t see it because it didn’t make a difference with the numbers that I used worked through it. We have replaced the previous threshold spreadsheet with a corrected one.
By Daren Mueller, Department of Plant Pathology
By XB Yang, Plant Pathology Department
By Roger Elmore, Department of Agronomy and Alison Robertson, Department of Plant Pathology
Corn is seemingly racing toward tassel and silking thanks to a spell of relatively good weather. Field appearances improve daily. As we scan the tops of canopies a few plants stand out, not because of height but because of color; yellow, bright yellow leaves seem to wave to us in the breeze. These trapped, sun-starved leaves emerge as splotches of bright yellow in a dark green sea of plants.
By Stephen K. Barnhart, Department of Agronomy
Flooding has damaged pasture and hay meadows across the state of Iowa. While most forage will likely recover, other areas that were eroded or silt- or sand-covered will require some reseeding. The following considerations may guide you in your planning and management.
by John Sawyer, Department of Agronomy
Earlier I provided observations in two articles (June 19 and June 26, 2008) on corn growth and response to nitrogen (N) applied in an anhydrous ammonia study being conducted at the ISU research farm between Ames and Boone. Following are some final observations (July 7, 2008).
By Stephen K. Barnhart, Department of Agronomy
New forage seedings are susceptible to a wide array of problems and stresses -flood, hail, drought, weed competition, insects, etc. Late summer can be a good time to ‘patch in’ bare or thin spots in forage stands or reseed entire fields. However there are some risks. The following steps will improve the chances for successful forage stand establishment in late summer.
By Roger Elmore, Department of Agronomy
Silk dates mark a milestone in growth and development of corn. This year in particular estimates of silk date are of interest since they provide an idea on timing of fungicide application as well as providing a look forward for conditions that might occur during this time critical for corn development. Crop simulation models are useful tools to project silk dates based on season-to-date weather conditions. Models also provide estimates of yield potential.
By Stephen K. Barnhart, Department of Agronomy
By Rich Pope, Department of Plant Pathology
Independence Day has come and gone, and scant acres of corn in most of Iowa have reached that old, outdated saw of knee high by the fourth of July. On my weekend trip to western Iowa, I saw corn ranging from V2 to VT! Admittedly, very little acreage was at either extreme, but it illustrates the continuing range of crop conditions that we will deal with through and after harvest this year.
