After a fairly normal planting season, most corn, soybean and wheat growers in Ohio added rain to their annual on-farm wish list for early summer. Well, they got it.
“Two weeks ago I said I wanted rain, but now I am ready to shut her down a little. We got another 1.5 inches last night and in the last two weeks we are almost at 8 inches of rain. Most of the rains have been .7 or .5 at a time. It has been nice and steady, but the ground is pretty well saturated now. I need to save some for August,” said Paul Ralston of Hardin County in yesterday’s Between the Rows report. “It is time to get some other things done instead of standing here dumping out the rain gauge.”
There has been measurable rain in most of Ohio every day for more than two weeks.
“This has been a remarkable pattern. Some areas have had locally 6 to 12 inches of rain since June 23, with barely a day or two without measurable rainfall,” said Ben Gelber, a meteorologist for NBC4 and NBC4i.com in Columbus. “This is not unprecedented, but certainly remarkable to have such a persistent feed of moisture from the Gulf. The problem is residual moisture — even as the upper level wind pattern shifts — that allows for recycling of water vapor into daily rounds of pop-up and organized storms associated with diurnal heating and small disturbances in the flow.
“We had a similar pattern of repeated storms and excessive rains in July 1992 with more than 15 inches in a few spots, and to some extent in July 2004 with 10 to 15 inches of rain northwest of Columbus.”
There does appear to be some sunshine on the way later this week.
“The key is to have an extended dry spell to evaporate water from the fields to lessen the effects of the hydrologic cycle,” Gelber said. “We should get a temporary break in the pattern later this week, beginning Thursday, through early next week, with drier, cooler air.”
This deluge that has inundated most of Ohio is the source of growing concern for wheat growers struggling to get the crop out of the fields. Fortunately for Bill Black in Pickaway County, wheat was ready and in the bin in between the showers.
“We finished on July 3. It was running anywhere from 14% to 17% moisture when we cut it. It is in the bin with the fan running,” Black said. “There was no straw baled and no double-crop beans planted. It was all we could do to get the wheat cut in time.”
Many further north, however, have not been so fortunate because the wheat was not yet mature when the rains came. Yields are generally strong, if the crop can be successfully harvested.
“Yields are good, but quality wheat is still an issue due to all the rain wheat growers have experienced,” said Bill Mullen, Seed Consultants, Inc. director of agronomic services. “A wheat grower north of Washington Court House, had the variety SC 1302 average over 100 bushels with a test weight at 62, which is the best I have heard so far. Part of his success is due to the fact that, at flag leaf, he applied fungicide and insecticide, which was well worth the money spent.”
Mullen has heard of other wheat yields ranging from 80 to 90 bushels per acre with test weights in the range of 58 or 60, which is a pound or two less than last year due to the moisture. In the northeast, some yields drop off significantly from central Ohio and northwest Ohio, Mullen said.
“I have not heard of much scab in fields except for some early maturities that have it but not to the degree we have seen in past. I have seen more black heads in fields due to the moisture issue as well,” he said. “There is some glume blotch in fields but not as bad as I originally thought it could be. For the most part, yields will be very good, test weight will be average, and the scab percentage lower than it has been in past. The moisture will be higher because of the rain, and there will be some disease affecting grain quality. Sprouting could be an issue as we get later in the harvest, especially north of I-70.”
Ohio State University Extension wheat experts Pierce Paul, Ed Lentz and Laura Lindsey agreed that harvest delays could lead to pre-harvest sprouting in some varieties in some areas.
“Once moisture is taken up by mature grain, stored reserves (sugars especially) are converted and used up for germination, which leads to reduced test weights,” they wrote in this week’s CORN Newsletter. “Even before visual signs of sprouting are evident, sugars are converted and grain quality is reduced. Since varieties differ in their ability to take up water, their drying rate, the rate at which sugars are used up, and embryo dormancy (resistance to germination), grain quality reduction will vary from one variety to another.”
Mold problems in fields are also a growing concern.
“To fungi, mature wheat heads are nothing more than dead plant tissue ready to be colonized,” they wrote. “Under warm, wet conditions, saprophytic fungi (and even fungi known to cause diseases such as wheat scab) readily colonize wheat heads, resulting in a dark moldy cast being formed over the heads and straw. This problem is particularly severe on lodged wheat. In general, the growth of blackish saprophytic molds on the surface of the grain usually does not affect the grain. However, the growth of pathogens, usually whitish or pinkish mold, could result in low test weights and poor grain quality.”
Soybeans are also suffering from the excess moisture.
“We know that a week after a rain, we will start to see the above ground symptoms of Phytophthora root rot on susceptible varieties. So, this week will be a good time to scout to see if the Rps genes in your varieties are still effective and if the field resistance/partial resistance levels are high enough,” said Anne Dorrance, OSU Extension plant pathologist in the CORN Newsletter. “When soil is saturated for more than three days and anoxia — low oxygen, high carbon dioxide — sets up, flooding injury occurs. Some plants will die and others will be set back until new roots form.
“To separate flooding injury from Phytophthora, dig up symptomatic plants. Pull on the outer epidermis of the roots. If it collapses between your fingers, it is Phytophthora or root rot caused by another watermold, Pythium. If you can pull off the epidermis and the nodules on the root and find the white root stele, it is flooding injury.”
In many areas, corn has responded favorably to the moisture, though ponded, saturated conditions can still be a concern.
“The extent to which ponding injures corn is determined by several factors including: (1) plant stage of development when ponding occurs, (2) duration of ponding and (3) air/soil temperatures. Corn is affected most by flooding at the early stages of growth. Once corn has reached the late vegetative stages, saturated soil conditions will usually not cause significant damage,” said Peter Thomison, OSU Extension corn specialist. “Since most corn in Ohio is approaching the silking stage, this bodes well. Although standing water is evident in fields with compacted areas, ponding has usually been of limited duration, so the injury resulting from the saturated soil conditions should be minimal. Moreover temperatures have been moderate.
“However, under certain conditions saturated soils can result in yield losses. Although plants may not be killed outright by the oxygen deficiency and the carbon dioxide toxicity that result from saturated soils, root uptake of nutrients may be seriously reduced. Root growth and plant respiration slow down while root permeability to water and nutrient uptake decreases. Impaired nutrient uptake may result in deficiencies of nitrogen and other nutrients during the grain filling stage. Moreover, saturated soil conditions can also result in losses of nitrogen through denitrification and leaching.”