Issue No. 5, Article 7/April 22, 2005
Planting Progress and Issues
The Agricultural Statistics Service reports that 35% of the Illinois corn crop was planted by April 17, on pace with the progress in 2004 and well ahead of average. This figure ranges from the teens in the northern and southernmost crop reporting districts to 73% in the West and West Southwest district. With dry weather continuing to midweek this week and planting going on almost everywhere, percentages will be much higher by this weekend. While early planting really helped the crop get off to a wonderful start last year, we have to keep in mind that early planting is no guarantee of a good corn crop; it's the weather after the crop is up and growing that makes most of the difference in yields from one year to the next in well-managed cornfields.
Weather forecasts at midweek indicate that the warm, dry weather we've been enjoying will not continue; rain and lower temperatures are predicted for the next week. This needn't discourage us too much, since we've already gotten close to, or even more than, the average growing degree-day accumulation for April, which is about 220 GDDs in central Illinois. Soils are also dry enough and warm enough on the surface that some rain and cooler tem-peratures will not seriously erode the soil conditions for crop growth. Thus, we wouldn't suggest holding off planting if rain and cooler temperatures are in the forecast, as long as forecasts are not for extreme events.
With many producers finished with corn planting by now, soybean planting is starting to get under way. We would have little reservation about early soybean planting once we're past April 20, as long as the soil is in good shape. With the expectation that soils will get cooler and wetter this week, it might be a good time to consider using seed protectant fungicide and also to plant at moderately shallow depth, around 1-¼ to 1-½ inches. Gary Cook, with the Illinois Crop Improvement Association, recently reported that some soybean seed from last year has more mechanical damage than usual, perhaps related to the large seed size and dry weather at harvest. This will not always show up as low warm germination, and it may not affect emergence percentage much if soil conditions are reasonably good. Keep in mind that soybean seed is a rather fragile package, though, and treat it accordingly.
Research that we did recently showed that using later or earlier soybean varieties when planting early seldom produces higher yields than using midseason varieties. It is more important to choose top varieties based on yield record than to try to adjust maturity depending on when planting takes place, especially if that means using varieties with unproven performance. Resistance to diseases, including SCN, also can be important, regardless of planting date.--Emerson Nafziger