Ag Issues

Crop Yields Depend on Fall Factors
The 2002 planting season is complete in Peoria County, although it was much longer than originally anticipated. After a rapid start, with record warm temperatures and dry weather in mid-April, May became wet and cold. Farmers dodged the rain showers as best they could through the month and sporadically planted field by field. Corn and soybean seed was finally finished up during the first two weeks in June.

The slow start creates an interesting scenario for this fall. Crops planted later tend to be harvested later. Once we get into mid-September, a number of factors come into play. First, there is the possibility of frost. If the soybeans are still green when the first frost arrives, it could decrease yields dramatically. The corn plant isn’t as susceptible to frost as soybeans. Second, as days grow shorter and temperatures decrease in the fall, the rate of crop dry down and fields drying out also slows down.

Any wet weather pattern that takes root simultaneously with harvesting could dramatically slow harvesting.

The ideal situation is to be able to harvest a crop when it’s dry. For corn, this is 15 percent moisture; it’s 13 percent moisture for soybeans. Does a farmer harvest early and pay extra fuel costs to dry it down or let Mother Nature do the drying but risk a wet pattern setting in and possibly losing a portion of the crop? Time will tell how temperatures and rainfall for the remainder of the summer determine the fate of the harvest season.

Pinning Down Land Usage

The Illinois Department of Agriculture is using two satellites orbiting 438 miles above Earth to get a picture of farmland conversion in the state. They are taking photographs of Illinois surfaces to create landscape maps than can distinguish between farm and non-farm land uses. By comparing these maps over time, the Ag Department will be able to track how much farmland was converted to non-agricultural uses, where the conversion occurred, and for what purpose.

The Illinois Department of Natural Resources and National Statistics Service are collaborating on the three-year-old project, known as the Illinois Interagency Landscape Classification project. The satellites photograph Illinois land surface by recording the colors each type of ground cover reflects, and are then converted into maps by computers programmed to identify ground cover.

Each pixel—or picture element—of a spectral image represents two-tenths of an acre. Ten scenes, each depicting an area of about 13,000 square miles, are required to map the entire state.

Completing a map can take up to two years because satellites pass each point on Earth only once every 16 days and cloud cover can prevent them from taking usable images during the growing season. The availability of two satellites increases the likelihood acceptable images will be captured.

The Illinois Department of Natural Resources will use the maps to monitor the state’s supply of woodlands, wetlands, and prairie, as well as the acreage of ponds, streams, and rivers. The National Agricultural Statistics Service will use the maps to verify the accuracy of its county crop acreage estimates. IBI