ALLENTOWN, Pa. — Farmers from eastern Pennsylvania gathered at Penn State’s Lehigh County Crops Conference on Jan. 30 to learn about nitrogen management and ways to improve wheat yields.
John Spargo, Penn State’s agricultural analytical services lab director, spoke on nitrogen management.
Moderately and poorly drained soils are most susceptible to nitrogen leaching, and a rainy spell only makes matters worse.
Spargo reminded the audience of the 4R’s of nitrogen application — right rate, right time, right place and right form — and cautioned against putting down all of a crop’s nitrogen at planting.
Sidedressing four to six weeks after planting allows time to follow the market price and weather, giving the farmer more information to assess the crop’s nitrogen needs.
Adaptive nitrogen management practices emphasize applying the element in a form that makes it to the plant.
Urea with a semi-permeable polymer coating is a time-released form of nitrogen, which can maximize the amount taken up by the crop over time.
NutrientStar, a certification program for nutrient management tools, offers comparisons on products.
Spargo recommended using late-season nitrate tests, particularly the late-season corn stalk nitrate tests.
The optimal testing window is a postmortem assessment between one-third milk line and three weeks black layer, and is $10 to send into the lab. Results below 700 ppm are likely limiting yields.
Penn State senior Extension educator Del Voight presented “High-Yielding Wheat Management,” providing an overview of strategies to get high yields without lodging.
With this winter’s mild weather, Voight told growers that now is the time to be out in the field assessing stands, taking tiller counts and scouting for weeds.
Growers don’t want nitrogen in the environment now for late plantings, but they need to see how things are growing and determine what’s next.
Identifying well-drained fields is key to a high-yielding stand.
Inputs and fertility controls are important. A grower has to invest for success.
High nitrogen can change a stand’s complexion or lead to lodging. Two weeks after greenup is a good time for application, Voight said.
Manure can increase a field’s organic matter, but it can also swing 100% in lab tests, and it should be tested accordingly and then spread evenly at a time when the ground is conducive.
Growers should take historical application factors into account when applying, Voight said.
The right varieties can have a big influence on yields. Penn State tested 61 varieties at its Rock Springs and Landisville farms in 2019, with yields between 71.7 to 93.8 bushels per acre.
Simply choosing a more vigorous seed can add 15-20 bushels per acre to a yield. Results of the variety trial are available at bit.ly/wheat-trials-19
Timing of a planting is another major factor for high yields.
If planted too early, a stand can get too much rank growth and is susceptible to powdery mildew and other fall diseases, as well as freeze damage.
If planted too late, especially in clay soils, seeds can uproot from heaving.
Late September is too early in the Lehigh Valley. Planting in the first half of October increases yields.
Planting rate and depth are also important. If planted too shallow, wheat pushes up and a farmer ends up spraying the plant roots, which will hinder a top yield. At emergence, farmers should see 25 plants per square foot.
Other sessions at the conference covered managing diseases and pests in soybeans, the realities of hemp production, and glyphosate and the environment.