The Chances for Timely Planting Diminish

May 9, 2002

COLUMBUS, Ohio - With soggy fields from persistent wet weather plaguing Ohio corn and soybean growers and more rain forecasted, timely planting appears to be getting further out of reach. But Ohio State University Extension agronomists say a good crop is still possible, even if planted as late as the end of May or first week of June. "If the world was perfect, we'd like to be finished with planting soybeans by May 20 and finished with corn by May 15, but that's not going to happen this year, is it?" said university agronomist Jim Beuerlein. "Planting all depends on what the rain is going to do. We need two to three days of good drying at a minimum before we can do anything." Only 11 percent of the corn has been planted in Ohio, compared to 64 percent planted at this same time last year. Planting is at least 10 days behind schedule and with topsoil moisture rated over 50 percent saturated, growers won't be rushing into their fields anytime soon. "We ended up with pretty late planting in 1996, where probably only 40 to 50 percent of the corn was planted by the end of May," said university agronomist Peter Thomison. "With the weather conditions the way they have been lately, many people are thinking we are going to be running into a year like that again this season." He said many growers are expressing concerns over delayed planting, but he emphasizes that good yields are still possible. "Growers are concerned that if we have these cycles of wet and dry weather, some acres may be pushed into late May and even early June," said Thomison. "But we could still be in pretty good shape and get good yields with corn planted as late as May 20 and even later." The corn crop's ability to adjust to delayed planting may bring some relief to farmers' growing pains. Thomison said many mid-to-full-season hybrids decrease their heat unit requirements (growing degree days or GDDs), or the time it takes for them to reach maturity before frost, the later they are planted in the growing season. This ability offers farmers the opportunity to keep the hybrids they originally intended to plant, rather than switching to short-season hybrids. "Traditionally, it was thought that a corn hybrid required a fixed number of GDDs, or heat units, to reach maturity. But we've learned in recent studies that corn can adjust to delayed plantings. Many hybrids actually require six to seven fewer GDDs per day of delayed planting, which gives us some flexibility with our hybrids," said Thomison. "So if a mid-to-full-season hybrid was planted in late May, it wouldn't have any problems in reaching maturity because of the decreased heat requirements." Thomison added that it is a good idea to stick to mid-to-full-season hybrids, even this late in the game. "Full-season hybrids have better yield potential than short-season hybrids. Also many short-season hybrids, especially those from more northern states like Michigan and Wisconsin, are not well-adapted to Ohio's and Indiana's growing conditions and grain quality and disease resistance won't be as good," he said. Thomison and Purdue University Extension agronomist Bob Nielsen have published guidelines to help Ohio and Indiana growers make decisions as to which hybrids to use in delayed planting situations. "One of the goals of the publication is to prevent growers from expending a lot of energy they don't have to," said Thomison. "It provides information as to which hybrids would be safe to use with planting delays through the second week of June." Purdue University's version of the publication will be available at Nielsen's Chat 'n Chew Café website at http://www.agry.purdue.edu/ext/corn/cafe/. Ohio State will release a version soon to the Crop Observation and Recommendation Network (C.O.R.N.) newsletter at http://corn.osu.edu. Thomison said that while the publication may be useful for growers in their decision-making process, the further delayed planting drags on, the more growers may consider switching out of corn altogether and planting soybeans instead. "Some growers are going to hold on to that corn until the end of May and depending on the forecast, will decide then to keep their crop or switch to soybeans," said Thomison. "Regardless of maturity, growers are going to be looking at a wet harvest. They may not want to contend with a 24 or 25 percent moisture content in October because that adds to their drying costs. They may want to maximize their profits and the bottom line may be that switching to soybeans may be more profitable for them." Soybean growers are seeing a bit more optimism during this time of delayed planting, said Beuerlein. "Soybeans adapt themselves to late planting conditions much more readily than corn does," he said. "So even if soybean growers plant a little later than usual, the crop should still do OK. We could still see good yields even with planting by mid-June if we have good weather following planting and no disease." Five percent of the soybean crop has been planted so far, 10 days behind the five-year average and the slowest start since 1998. Thomison and Beuerlein recommend increasing the seeding rates 5-15 percent in corn and soybeans if planting continues into June, especially for no-till or reduced tillage fields. Thomison also recommends that growers pay close attention to nitrogen management. "Nitrogen that was applied to fields in April may be subject to denitrification. It all depends on the soil conditions and how much nitrogen was applied." Despite the immediate concerns growers have, Thomison said the real problems could come later on in the summer, especially if weather conditions are hot and dry. "What conditions will be like in July and August is really what is going to make the crop," he said. "If soils now aren't conducive for good root development and we get shallow roots, then we could have a really poor crop if hot weather hits us later in the growing season."

Author(s): 
Candace Pollock
Source(s): 
Jim Beuerlein