Late bean leaf beetle, profitable wheat production guide
After all the dry summer we’ve experienced, the National Weather Service is predicting that our rainfall is going to be above normal for the first few weeks of September.
They are calling for a few inches Friday night, and into Saturday morning. Normal rainfall is a little over an inch for the first half of the month. Rainfall will average 1 to 2 inches during this period. Isolated totals will of course be higher and lower than these amounts as we saw with the varied rain amounts with last weekend’s rains here in Delaware County. Some reported more than two inches, while others got under an inch. Looks like things will dry out some next week.
I want to remind you that if you would like to purchase discount tickets for the “Farm Science Review,” our office will have them for sale until Sept. 14. Cost is $5 they are $8 at the gate. The review will run Sept. 18 through Sept. 20.
Late bean leaf beetle: Many soybean fields around the county are starting to yellow and mature, but there is concern for the late maturing fields that are, and will remain, green for the next few weeks. According to Ron Hammond, OSU Extension Specialist, as fields mature, bean leaf beetle adults will leave and look for soybean fields that are still green to continue their feeding prior to overwintering. Because of very high numbers that can come into green fields, the soybeans remain susceptible to pod feeding. Growers are urged to monitor any field that is still green for their presence and feeding activity. Hammond says that treatment is warranted if feeding injury is reaching 10 to 15 percent of the pods and beetles are still actively feeding. Remember that if treatment becomes necessary, growers should note the preharvest interval on the insecticide label so that they can still harvest on time. Late maturing fields could be those late planted, including those doubled or intercropped. Special concern should include soybeans grown for seed or as food grade soybeans.
Profitable wheat production in five steps: The 2012/2013 winter wheat season is fast approaching and as growers make preparations for planting. Pierce Paul, OSU Extension Specialist, Plant Pathology, along with other experts, say there are a few management decisions that are important for a successful crop. Nearly every farm in Ohio has a field or two that could benefit from planting wheat, if for no other reason than to help reduce problems associated with continuous planting of soybeans and corn. According to Paul, consistent high yields can be achieved by following a few important management guidelines. The important management decisions listed below are recommenced by Paul to help with decisions Ohio wheat producers need to make at fall planting time to produce a crop with satisfactory economic returns:
ONE: Select high-yielding varieties with high test weight, good straw strength and adequate disease resistance. Do not jeopardize your investment by planting anything but the best yielding varieties that also have resistance to the important diseases in your area. Depending on your area of the state, you may need good resistance to powdery mildew, Stagonospora leaf blotch, and/or leaf rust. Avoid varieties with susceptibility to Fusarium head scab. Plant seed that has been properly cleaned to remove shriveled kernels and treated with a fungicide seed treatment to control seed-borne diseases. The 2012 Ohio Wheat Performance Test results can be found at oardc.osu.edu/wheattrials.
TWO: Plant after the Hessian Fly Safe date for your county. This date varies between Sept. 22 for northern counties and Oct. 5 for the southern-most counties. Planting within the first 10 days after this date minimizes the risk of serious insect and disease problems including Hessian Fly, aphids carrying Barley Yellow Dwarf Virus, and several foliar diseases. Planting before this date has lowered yield by 7 to 20 percent in research trials due to disease and insect problems. On the other hand, planting late (generally after Oct 20 in northern Ohio) can reduce the number of primary tillers that develop in the fall and increases the risk of cold temperature injury. The Hessian Fly free dates can be found at ohioline.osu.edu/iwy/flydates.html.
THREE: Optimum seeding rates are between 1.2 and 1.6 million seeds per acre. For drills with 7.5 inch row spacing, this is about 18 to 24 seeds per foot of row with normal sized seed. When wheat is planted on time, actual seeding rate has little effect on yield, but high seeding rates (above 30 seeds per foot of row) increase lodging. There is no evidence that more seed is better, it only costs more money. If planting is delayed to more than three weeks after the Fly-Free date, plant 24–26 seeds per foot of row which is 1.75 million seeds per acre.
FOUR: Planting depth is critical for tiller development and winter survival. Plant seed 1.5 inches deep and make sure planting depth is uniform across the field. No-till wheat into soybean stubble is ideal, but make sure the soybean residue is uniformly spread over the surface of the ground. Shallow planting is the main cause of low tiller numbers and poor over-winter survival due to heaving and freezing injury. Remember, you can not compensate for a poor planting job by planting more seeds; it just costs more money.
FIVE: Apply 20 to 30 pounds of actual nitrogen per acre at planting to promote fall tiller development. A soil test should be completed to determine phosphorus and potassium needs. Wheat requires more phosphorus than corn or soybeans, and soil test levels should be maintained between 25 to 40 ppm for optimum production. If the soil test indicates less than 25 ppm, then apply 80 to 100 pounds of P2O5 at planting. Do not add any phosphorus if soil test levels are higher than 50 ppm. Soil potassium should be maintained at levels of 100, 120 and 140 ppm for soils with cation exchange capacities of 10, 20, or 30, respectively. If potassium levels are low, apply 100 pounds of K2O at planting. In Ohio, limed soils usually have adequate calcium, magnesium and sulfur for wheat. Soil pH should be between 6.3 and 7.0.
The key to a successful wheat crop is adequate and timely management. The above recommendations are guidelines that may be fine-tuned by you to fit your farming operation and soils. They also assume that you are planting wheat in fields that are adequately drained. You can review more details on these, and other, research-based wheat management recommendations at ohioline.osu.edu/iwy/index.html.
Rob Leeds is the Delaware County OSU Extension Educator.