SALEM, Ohio — Could the cold winter weather finally be gone?
The National Weather Service forecast shows daytime highs near 60 heading into April Fool’s Day in northeast Ohio and western Pennsylvania, and farmers, who have endured one of the coldest winters in the last 20 years, hope it’s not a joke.
Climate experts say the region is about two to three weeks behind season, with temperatures 3-5 degrees below normal for the first 10 weeks of 2014 — the coldest start to a year since 1994. The final week of March, temperatures were 5-15 degrees below normal.
As temperatures finally warm, farmers will find themselves with fewer planting and tillage days to work with, and plenty of questions about the consequences.
Paul Knight, Pennsylvania state climatologist, said one of the benefits is the transition from cooler to warmer temperatures has mostly been dry — thus reducing the problem of heavy flooding.
“The slow return to more seasonal temperatures has been accompanied by mainly dry conditions so that the flooding risk has been diminished,” he wrote in the most recent edition of Penn State’s Field Crop News.
Looking ahead
Jim Noel, a hydrologist with the National Weather Service in Ohio, said temperatures will likely remain below normal into a good part of April, with precipitation near normal.
Based on historic years like the current winter, the last date of a freeze is usually one to two weeks later than normal. This would push back a typical last freeze from about April 20 to closer to May 1, he wrote in the most recent edition of CORN Newsletter.
However, Noel said these freeze temperatures tend to be less intense at that point as typical hard freezes (below 26-28 degrees) end at about normal time.
While this is not the kind of start farmers want, it’s still early — very early.
Noel said in similar weather years, Ohio corn yields actually average 7 percent above trend line, soybeans were 3 percent above trend line and wheat ended up near trend line.
Priorities
The delay may mean re-prioritizing some field operations.
“Compaction from applying fertilizer or doing tillage in wet soils can leave soils in worse condition than before, even if the surface looks a little drier afterwards,” said Emerson Nafziger, a University of Illinois crop sciences researcher, in a released statement.
Nafziger reminds farmers that planting in early April “almost never produces yields higher than planting in late April,” and can lower yields even when stands are good.
Planting in early April into good soil conditions, however, with soil temperatures expected to be on the rise after planting, is a sound practice, especially when there are a lot of acres to plant and starting early is the only way to finish on time.
Bittersweet
Farmers often think of deep freezes as a good way to condition the ground through winter, killing insects and reducing soil compaction. But Nafziger said the freeze may not have reduced compaction as much as farmers had hoped, because of how deep the freeze was and how long it lasted.
The problem was, the soil was frozen too long and there were not as many freeze-thaw cycles as usual.
“Soils that stay frozen, don’t repeat this cycle often enough to do much good,” he said. “The freezing and thawing of the surface soils that we’re seeing now will help loosen them some, but we can’t expect that effect to extend more than a few inches deep.”
Wheat crop
For farmers who already have a crop in the ground — like winter wheat — the cold winter may have already caused some damage.
Small grains researchers with OSU, however, say that wheat is a cold season grass that can tolerate “fairly harsh” winter conditions.
How wheat performs in cold weather depends on the variety and requires a period of growth when temperatures are between 30-60 degrees, followed by slowly declining soil temperatures.
After hardening, wheat can tolerate temperatures between zero-10 degrees, especially when there is good snow cover.
The growing point of wheat is below ground until conditions are warm in the spring, but extremely cold conditions can still cause damage to the plant. However, plants are only killed by low temperatures if the crown (lower stem) is damaged.
Although there were negative air temperatures in Ohio, soil temperatures remained in the upper 20s to low 30s.
“In general, I’ve been impressed with the way the winter grains have tolerated the winter temperatures,” said Greg Roth, Penn State professor of agronomy.
Roth said his biggest concern is fields of wheat that were late planted and had less time to establish. Some of these fields are showing signs of mortality, compaction and heaving.
If the crop is salvageable, Roth said farmers may want to consider an early application of nitrogen to stimulate growth. Or, if the stand is too poor, he said it may be best to forget the wheat, and plant corn or soybeans.
Also, some fields may have had damaged from areas where melting snow left standing water that later became ice. Standing water and especially ice on plants for several days may lead to “suffocation” of the crowns, which may cause weakening of the stand in those areas or complete loss of plants.
Evaluating yield
OSU researchers say fields should not be evaluated until completely green from warmer temperatures for at least 10 to 14 days. Stand evaluations will be more accurate at this time.
Yield potential is reduced if tiller numbers fall below 25 per square foot after green up.
Farmers should pick about 10 to 15 spots in the field and count the number of plants per foot of row. A stand with an average of about 12 plants per foot of row may still result in a good population of head-bearing tillers per acre.
For those fields with tillers, 15 tillers per square foot is considered minimum for an economic crop.
The number of tillers per square foot is equal to the number of tillers in 19.2 inches of 7.5-inch wide rows. Studies have shown that under adequate weather conditions, tillering may compensate for relatively poor initial stand establishment.
