Farm and Weather Summary Northwest Research and Demonstration Farm

Includes: Farm Comments Crop Season Comments Weather Comment

Northwest and Allee Farms Summary

Includes: Northwest Research Farm Summary Allee Demonstration Farm Summar

Soybean Aphid Threshold

Soybean aphid has been a major pest for producers in Northwest Iowa since their first major outbreak in 2003. Control measures for managing this pest are warranted almost every growing season and much research is being done on managing this pest. Insecticide applications have been the sole management technique for soybean aphid and will continue to be important in the future. An economic threshold of 250 aphids/plant is the current threshold level recommended by Iowa State University. This study was conducted to determine if the current recommendations are useful in managing soybean aphid and maintaining profitability for producers

Tillage System and Fertilizer Placement Methods for Corn and Soybean Production

No-till management results in little or no incorporation of crop residues and fertilizer with soil. Subsurface banding phosphorus (P) and potassium (K) fertilizers with planter attachments or before planting could be more effective than broadcast fertilization because both nutrients accumulate at or near the soil surface. A long-term study was initiated in 1994 to evaluate P and K fertilizer placement for corn and soybean managed with no-till and chisel-plow tillage

Yield Response of Planting Corn in Early April

Corn is planted earlier each year, which is one important component in maximizing grain yield. Earlier planting dates can be attributed to larger farms, less spring tillage, improvements in corn hybrids, improved drainage systems, and better seed treatments. Research conducted at the ISU Northwest Research Farm from 2006 through 2009 showed that the planting window for 98 percent or greater yield potential in northwest Iowa is April 15 to May 9. A 95 percent or greater yield potential can be realized from April 15 to May 18. A study was conducted from 2009 through 2011 at the Northwest Research Farm to determine how corn planted in early April compares with corn planted in the recommended planting window for the area

Phosphorus and Potassium Rates and Placement Methods for Corn and Soybean Managed with No-till or Tillage

No-till management for corn and soybean results in little or no incorporation of crop residues and fertilizer with soil. Subsurface banding phosphorus (P) and potassium (K) fertilizers with planter attachments could be more effective than broadcast fertilization, because in no-till with broadcast fertilizer, both nutrients accumulate at or near the soil surface. A long-term study was initiated in 1994 at the ISU Northwest Research Farm to evaluate P and K fertilizer placement for corn and soybean managed with no-till and chiselplow tillage

Evaluation of Narrow Row Soybeans

Producers continue to look at different management practices to increase corn and soybean yields. One area of interest is planting corn and soybeans in narrow rows. Traditionally, these crops have been planted in row widths of 30 to 38 in. Planters on the market today have the capability to plant corn and soybeans in 15- and 20-in. rows, as well as in twin rows that are spaced 8 in. apart. This study was set up to evaluate the yield impact of planting soybeans in 15-in. rows versus the traditional 30-in. row spacing

Comparison of Twin Row and 30-in. Row Corn

Producers continue to plant corn at higher plant populations each year with the introduction of more stress-tolerant hybrids. As row width stays the same, plants are growing closer together, which leads to more competition among plants. Planting corn in narrower rows allows more equidistant spacing of plants and less competition. Switching to narrow rows (15 or 20 in. rows) requires additional equipment to spray and harvest. Planting corn in twin rows that are spaced eight inches apart and centered on 30-in. rows is one system that allows more equidistant spacing and would not require changes in spraying or harvesting equipment. A study comparing twin rows to single 30-in. rows at various populations was conducted in 2010 at the Northwest Research Farm

Northwest and Allee Farms Summary

Includes Northwest Research Farm Summary, Projects at Sutherland and Doon and Allee Demonstration Farm Summary

Impact of Rolling on Soybean Yields

Rolling soybeans has become very popular in the past few growing seasons, especially in north central Iowa. Reasons for its popularity include, pushing rocks beneath the cutting height of bean heads, less dirt in the combine and cleaner beans, faster cutting speeds, less damage to cutting systems, and increased soybean yields. The last claim was studied at the Northwest Research Farm in 2009 and 2010 in both tilled and no-till conditions. Both tilled and no-till studies included a control treatment and rolling the soybeans pre-emerge and post-emerge when the beans were in the V1 stage of development. Soybean plots were rolled with a 20 ft Degelman Landroller from Custom Made Products in Humboldt, IA