MANHATTAN – Recent abundant rainfall resulted in a flush of new growth in some Kansas wheat fields, sparking development of late-developing tillers. In some areas, the new tillers have created a second canopy of green heads along with the main canopy of ripe heads, according to Kansas State University’s Jim Shroyer.

Rainfall across the state averaged 7.73 inches in May, which was 188 percent of normal and the third highest May average in 120 years, according to the Kansas Weather Data Library.

“Wheat heads that form this late in the season in a crop otherwise nearing maturity usually add very little to the overall yield of a field,” said Shroyer, who is a crop production specialist emeritus with K-State Research and Extension. “If these late, green heads are not close to being ready to harvest when the majority of the crop has dried down, it’s best to start harvesting the field anyway.”

Waiting for the green heads to mature would risk grain losses due to shattering or hail damage, he said. With wheat varieties that tend to shatter easily, producers should start harvesting when the field reaches 15 percent moisture.

Most of the immature grain and green plant parts will go out the back of the combine when the crop is harvested, but enough may go into the bin to increase the dockage and overall moisture level of the load. Combine settings can help minimize the problem, but not eliminate it. Any immature grain that goes out the back of the combine could result in greater-than-usual amounts of volunteer wheat this summer – a situation Shroyer encourages producers to monitor closely and control accordingly.

“The situation is a little different where the main canopy is several weeks away from being mature,” he said. “In this instance, the green tillers could develop quickly enough to add a significant amount to the yield potential. Still, unless the green tillers make up more than half of the heads in the fields, it’s probably best to just start harvesting when the majority of heads are ready to go if there is a maturity difference of several days or more between the ripest and least developed heads.”

Waiting for the green heads to ripen might lead to shattering of the more mature heads, he added.

Growers who are harvesting wheat with some green heads present should take special care to measure the moisture content of the grain if they plan to store it on the farm, and use air aggressively to dry it if the moisture content is high, Shroyer said.

In its weekly update, the U.S. Department of Agriculture rated Kansas wheat 2 percent excellent, 28 percent good, 41 percent fair, 19 percent poor and 10 percent very poor as of June 7. At 98 percent, almost all of the crop had headed, near 99 percent at the same time last year and the five-year average.