August 30, 2014

Subscriber Login

Cool, wet soild delays planting this spring PDF Print E-mail
Wednesday, May 14, 2014 8:00 PM


Putnam County Extension

Ag Educator


Mark Badertscher, Hardin County Extension Educator, summarized and wrote about some of the following planting issues in Northwest Ohio this spring.

Putnam County farmers have made a lot of progress this past week in getting both corn and soybeans planted. Cool, wet soils have delayed the start of planting season this spring because farmers generally prefer to plant corn in late April to early May. However, the calendar doesn’t always determine the best time to put the crop in the ground. Other factors that come into play are temperature and soil moisture levels.

The soil temperature must be warm enough for corn to germinate and corn needs a soil temperature of at least 50 degrees to germinate. This temperature should be measured at a depth of 1.5 to 3 inches in the soil. Although the soil may be dry enough to plant, if the soil temperature is not warm enough, the seed will not germinate. Current soil temperatures are around 48-53 degrees Fahrenheit but should be warming up as night temperatures start to rise.

Seed germination is dependent on enough moisture in the soil to cause the seed to swell, but if too much moisture is present, the seed and shoot can rot. According to OSU Plant Pathologist Anne Dorrance, seeds that are exposed to cool, wet soils become subject to pathogens, which can infect seeds and hurt seedling growth. One of the most common pathogens for corn and soybeans is Pythium. There are 25 different species of Pythium (Dorrance, CORN 2014-10), which can cause damage to seeds and growing roots. Farmers should plant into well drained soils and use seed treatments to help prevent plant diseases caused by Pythium.

Another factor that can affect the growth and development of corn and soybeans is soil compaction. If soils are too wet when planting occurs, compaction restricts air and water movement through the soil. Many farmers now plant crops using conservation tillage or no-tillage which limit soil compaction and reduce soil erosion.

Soybean germination begins when soil temperatures reach 50 degrees and moisture is present at the planting depth of 1-1.5 inches. Do not plant early if the soil is excessively cold or wet. Slower germination and compaction can negate the benefits of the earlier planting date. Soybean yield tends to decrease when planting after May 10; however, any benefits of earlier planting may not be realized if soil conditions are too wet or too cold.

Soybeans are an incredibly flexible crop. In 2011, only 4 percent of the Ohio soybean acres were planted by May 22. Last year, 45 percent of the soybean acres were planted by May 19. However, the state average soybean yield in 2011 was only one bushel/acre less compared to 2013. Clearly, the weather in the remainder of the growing season is also important. (Dorrance and Lindsey, CORN 2014-12)

Although the soil temperature and moisture are important factors when planting corn and soybeans, there does come a time when crop yields are affected by planting date. Usually this date is between mid-May or even later for corn, depending on weather conditions. After May 20, farmers may consider changing seed varieties for corn to an earlier maturing hybrid to reduce possible yield losses. (Thomison and Culman, CORN 2014-10)

According to Andy Michael, OSU Entomologist (CORN 2014-12), there are two insect pests (black cutworm and seed corn maggot) that need to be scouted. Penn State and Purdue are reporting significant flights of black cutworm moths, which are migrating and lays eggs in corn.

Stand loss of corn is generally associated with below-ground feeding injury, which occurs below the growing point. Fields with significant ground cover and weed presence tend to be more infested. This is not a widespread pest in Ohio and most infestations are light if we have them. For more information on black cutworms and seed corn maggot, go to

During this planting season it is important to be aware of slow moving tractors, trucks and equipment on the roads during all hours of the day. In addition, fertilizer and sprayer equipment will also be out doing their job. This equipment is wide and travels slowly compared to a car on the road. Look for equipment, flashing lights and slow moving vehicle (SMV) signs. This is especially true when coming over a hill or around a curve. Give the farmers and commercial fertilizer/pesticide applicators a chance to do their jobs so they can get their work done in a safe and efficient manner.


Add comment

Security code