SALEM, Ohio — You could have stood outside most of this summer and barely broke a sweat. Cooler-than-usual weather saw daytime highs in late July and most of August anywhere from 10-15 degrees below normal.
It felt pretty good — if you like 70-degree weather. But the duration of the cooler temperatures — which in some parts of Ohio and Pennsylvania exceeded a month — has likely had some effect on the 2013 harvest.
The question is, how much?
Not much, according to Peter Thomison, a professor with Ohio State University’s Department of Horticulture and Crop Sciences.
“Corn actually yields best with moderate temperatures (and adequate soil moisture),” he said in an interview with Farm and Dairy, and in a recent article for OSU’s C.O.R.N. Newsletter.
Related: Farmers discuss cold growing season
“Temperatures that occur in Ohio in July and August (especially at night) are often warmer than optimum for corn.”
The ideal daytime temperatures for corn are about 80 to 86 degrees and higher, if moisture is plentiful at all times.
Heat stress
Thomison said that contrary to belief, past research shows that warm temperatures adversely affect yield potential.
That’s because warm temperatures — above the mid 80s — tend to cause wasteful plant respiration and a shorter number of growing days, which lowers the amount of time the plant has for dry matter accumulation.
This year’s mild weather, Thomison said, will likely allow the corn plants more time to fill out, which will lead to “higher weights and higher yields.”
He expects good yields from soybeans as well, although he acknowledged there could be a shorter window for farmers who plant double crops after wheat and corn, due to the length of time it has taken for the primary crops to mature.
In the latest Crop Progress report from the National Agricultural Statistics Service, just 42 percent of corn nationwide was at or beyond the dent stage as of Sept. 1. That’s 42 percentage points behind last year, and 19 percent behind the five-year average.
Good quality
Corn quality, however, appears pretty good — at least in Ohio and Pennsylvania. In Ohio, 49 percent of the corn is good, 31 percent is excellent, and only 4 percent is below fair, as of Sept. 8. In Pennsylvania, corn dented is 59 percent — two percentage points behind the five-year average. And in Pa., 86 percent of the corn rates good to excellent.
On the forage side, farmers have battled a number of issues with the cooler weather, including some obvious challenges drying hay during extended wet periods.
“We’ve had a see-saw,” said Stephen Boyles, OSU Extension beef specialist. “Some places the weather has been great, but in other places the cooler weather may slow the growth.”
For cooler season grasses, he said the cooler weather has been beneficial. But the opposite is true of grasses that need warmer temperatures.
The reports from NASS show that farmers in both Ohio and Pennsylvania are behind on the number of cuttings of hay — in large part from a wet spring.
Alfalfa behind
In Pennsylvania, third and fourth cutting Alfalfa stand at 93 and 45 percent respectively — which is behind the five-year average of 96 percent for third cutting, and 51 percent for fourth cutting.
Ohio farmers have harvested 72 percent of third cutting. There is no five-year average for comparison, but hay production in Ohio is noticeably behind, along with most of the other major crops.
“Producers are significantly behind on harvesting the second and third cutting of hay, but crop condition remains good,” according to NASS.
Boyles said farmers will likely see good tonnage of hay per acre, but he cautioned there will be some poor quality hay. He recommends farmers who are feeding high-production animals have their hay tested, so they can feed the lowest quality hay first, and keep the best for later.
One of the advantages of a cooler season, he said, is that livestock are generally doing better — in terms of what time of day they eat and how much they eat. The eating habits of cattle are directly tied to the weather. Their ruminant stomachs produce a lot of heat — more than people often realize.
“They are much more comfortable at cooler temperatures than we are,” he said.
What’s ahead
Many are predicting corn maturity to be 10-20 days behind normal, and the next few weeks will be important.
As Thomison says, the slower, milder growing seasons often produce the best yields. But that can mean a shorter harvest window and more issues with fall and winter moisture.
He says growers may want to consider this possibility when they estimate fuel costs for drying grain. Looking back, farmers will remember the season of 2009, when a cool, wet season allowed for rot and major growth of mycotoxins.
Thomison said the yield potential looks good so far, but that other issues can creep in.
In his weekly weather update for C.O.R.N. Newsletter, Jim Noel a hydrologist with the National Weather Service, says to expect a warm and dry start to September, with temperatures relaxing throughout the month. The second half of September, he says, will likely turn cooler and wetter.
