Integrated Crop Management News

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High Yields, Low Grain Prices: Manage Phosphorus and Potassium Wisely

October 21, 2016
Phosphorus and Potassium results graph

Bumper grain yields are being harvested from most Iowa fields this fall. However, due to low crop prices producers are thinking of reducing phosphorus (P) and potassium (K) fertilizer application rates. A few important management options should be considered when making decisions with unfavorable crop/fertilizer price ratios.

Cereal Rye Suitability for Roller Crimping and No-till Applications

October 19, 2016
Roller crimper photo

This time of year brings harvest, preparations for winter, and the planting of cover crops. Cereal rye is a popular and versatile cover crop that is planted in the fall and terminated in the spring. Traditional termination methods include chemicals, mowing, tilling, and even crimping prior to planting of the row crop. The roller crimper, originally designed by the Rodale Institute, is used to crimp the cereal rye stem in several places (Fig. 1). The flattened rye can create a mulch bed on top of the soil.

2016 Harvest Grain Quality Update

October 19, 2016
Dewpoint Temperatures graph

Iowa has had relief from the constant, late-September rains that were setting up for a difficult harvest season. As a result, the average grain moisture has fallen to a more typical 18-21%; lower in areas of lesser rainfall and vice versa. The potential for field drydown normally declines rapidly after mid-October. The issues of field mold that we reported in late September remain but shouldn’t be intensifying. Overall, the storage properties of 2016 will be average or below average, especially in wetter areas.

More SCN-Resistant Soybean Varieties Than Ever, but Diversity of Resistance is Lacking

October 18, 2016
Article on SCN-resistant soybean varieties

Nearly 40 years after its discovery in the upper Midwest, the soybean cyst nematode (SCN) continues to be a highly damaging pathogen of soybeans in Iowa and surrounding soybean-producing states. SCN is most damaging in hot, dry growing seasons, but yield losses of 10% to 25% or more can occur in years when temperatures are moderate and rainfall is average or above average. Growing SCN-resistant soybean varieties can slow the build-up of SCN population densities (numbers) in the soil and produce profitable soybean yields in SCN-infested fields.

Clean Combines to Avoid Weed Seed Contamination Across Fields

September 27, 2016
Weed Seed Trail from combine image

Removing biomaterial to avoid moving weed seeds between fields can be a daunting task. Typically, combines hold 125-150 lbs of grain and biomaterial after the unloading auger has operated “empty” for one minute. A true clean-out requires about six hours to remove as much biomaterial as possible. While a thorough, top-to-bottom cleaning of the combine is best to avoid the spread of weed seeds between fields, spending 15 to 30 minutes cleaning the combine before moving it out of the field will still remove some biomaterial.

Consider Combine Adjustment for Wet Field Conditions

September 27, 2016
Harvesting corn image

Coarse grains such as corn and soybeans usually thresh relatively easily, but wet field conditions may slow field drying. Rotor speed should not be increased and concave clearance should not be decreased more than necessary for threshing, but spongy corncobs or damp soybean pods may be more difficult to thresh. Greater rotor speed or reduced concave clearance may be necessary in these conditions.

Scout Now for Ear Rots

September 26, 2016
Diplodia Ear Rot image

Corn coming in to the Iowa State University Grain Quality Lab from field trials in central, northeast, and southeast Iowa has been affected by a variety of ear rot fungi, and many individual ears display symptoms of multiple fungi.

Management of Flood-Submerged Grain

September 25, 2016

Grain submerged by uncontrolled flood waters is considered Adulterated under the Food Drug and Cosmetic Act. This policy dates to 2008 when grain storages in Cedar Rapids were inundated, and has been applied to several situations since then. Adulterated material cannot be put in commercial facilities of any type, where there would be a chance of entering human or animal food. There have been flooded (over the grain height) fields in northeast Iowa since mid-September. Late September rains have increased the scope of this problem to north central and east central Iowa, as well.

Wet Weather Creates Challenges for Harvest

September 25, 2016
Cob rot image

The 2016 growing season was wet with two distinct temperature patterns—hot during early pollination and cooler in August. Most of Iowa had 125% up to 200% of normal rainfall up to Labor Day, and even more after Labor Day. The outlook going forward into October is continued above average temperatures and above normal rainfall.