Each Monday morning during the crop season, campus and Iowa State University Extension field crops specialists participate in a teleconference to share what they are observing in fields across the state. Due to the Memorial Day holiday, Iowa State University Extension field crops specialists submitted the following e-mail reports from their areas:
Corn and soybean planting is complete. The majority of corn is at V3 and soybeans are at VC. The first alfalfa crop harvest is about 35 percent complete. The April frost delayed crop development by 10 to 15 days. The northernmost tier of counties still has alfalfa that is too immature for normal first crop harvest of dairy-quality hay but should be harvested in 7 to 10 days, weather permitting. There were no significant pest problems. A much-needed rain fell across the entire NE area Wednesday and Thursday. This should help those areas that were suffering uneven emergence of corn and soybeans due to dry soil conditions, and herbicide effectiveness in the same dry soil, although I'm sure there will be some weed escapes from the dry period that will require POST herbicide applications. --Brian Lang, NE Iowa
Almost everyone finished bean planting last week even with the 1.5 to 3 inches of rain on Wednesday and Thursday; heaviest rains occurred along Interstate 35. Corn is in the VE-V3 stage. Soybeans are in the just-planted to VC stage. Modest bean leaf beetle numbers were observed. Alfalfa is in the 180-190 Relative Feed Value stages. First cutting will start later this week after the predicted weather fronts move through. --George Cummins, NC Iowa
In general, the areas that needed rain the most received the most: 0.25 to about 1.25 inches. Questions and farm visits are generally revolving around stand issues (alfalfa, wheat, corn, and soybeans), nitrogen on corn, and bean leaf beetles on soybean. Haymaking is underway. Yields appear to be ranging from 2550 percent of normal. Potato leafhoppers can be found in sweep nets. Corn is V1-V5, mostly V4-V5. Plants appear generally healthy but with some NH3 burn.
Canada geese enjoy a wet corn field south of Ogden. (Keven Arrowsmith)
Some producers who have not raised corn on corn for a long time have forgotten about the early-season streaking that can occur when nitrogen fertilizer is knifed in. Soybeans are VE-V1, mostly VE-VC. Crusting issues are inhibiting soybean emergence. Bean leaf beetles are noted, but so far no commercial soybean fields warrant treatment. --Virgil Schmitt, SE Iowa
Southern Iowa received about an inch of rain this weekend. Some corn fields are looking "woolly." Weeds are as big as emerging corn. Corn planting is virtually finished. There may be a little replant due to wet feet, and some hay fields may be replanted to corn. Corn is VE-V5; early-planted fields look good. Fields planted between rains have poor stands; later planted fields look good. A few reports of black cutworm (2% feeding), larvae ¼ to ½ inch long. Soybean is about 80 percent planted and in the VE-V2 stage. Some alfalfa growers will lose 30-40 percent of stand, especially in 1- to 2-year-old stands. About 10 percent has been harvested, but most are going to wait an extra week to 10 days to cut. Wheat is headed. Yellow dwarf virus and rust are beginning in barley. Septoria leaf blight has been found. Oats are heading. Area pastures look good. --Mark Carlton, S Iowa
Soybean planting is almost complete. There are three distinct corn crops--April 21, May 3, and May 14 planting dates; all look good. Corn on corn looks decent. Soybeans are good. The wind has kept people out of the field for post-spraying; some corn fields are going to need it soon. --Paul Kassel, N Iowa
Except for corn planted about April 29 (rootless corn syndrome fields), the rest is progressing quite well, although weedy. Most corn is at V2-V5, a few at V6. Quite a few fields have yellow plants but should be OK. The surface is dry in many places. Last week the area averaged about one-half inch of rain, ranging from 0 to 2+ inches in small areas. The surface moisture was needed to get some of these nodal roots established.
Most replanting is complete and is emerging. Beans are 98 percent planted; 70 percent has emerged. Lately, bean leaf beetle pressure doesn't seem too bad. Many acres (Highway 10 and south) have been treated for alfalfa weevil. Some fields treated after harvest didn't green up. Approximately 24 percent of the alfalfa has been harvested so far. One field was 30 inches and starting to bloom. This area could use a rain, followed by several dry, low-wind days. --Joel DeJong, NW Iowa
This article originally appeared on page 161 of the IC-498(12) -- May 29, 2007 issue.