Group IV soybeans are big yielders If you're going to plant full season soybeans, plant early, unless you're also a tobacco farmer. That's the message coming out of Delta and Pine Land's soybean research station in Hartsville, S.C.. Since 1997, Group IV soybeans planted in April have frequently out yielded full season soybeans planted in May and June. Early planted Group IV soybeans, both irrigated and dryland, have produced significantly higher yields than full season soybeans planted later in the spring.

"You can plant soybeans before you plant cotton and pick before you pick cotton from Georgia to 40 miles south of the Virginia border," says Chris Tinius, Delta and Pine Land's director of soybean research.

Early in, early out "Get the Group IV soybeans in by April 20 and get them out by the end of August. That's not going to happen if you are a tobacco farmer. But most other farmers can find the time to take advantage of this early soybean production system. We're not advocating this early system to replace double-crop soybeans. But, if you're going to plant full season soybeans, this is an attractive alternative to planting in late May or June."

Tinius first realized the high yield potential of early planted Group IVs when he examined soybean yield data at the research station back in 1997.

He was surprised to see that DP 3478 soybeans that produced yields in the low 20 bushel range when planted in May, made an eye-popping 69.7 bushels when planted in early April.

"The difference was the weather during pod fill," Tinius says. "The main advantage to a dryland farmer in this area is to get the beans through seed fill in July rather than in August when it can be hot and dry. Growers who are concerned about diseases when they plant in cooler soils in April can spend $2 to $2.50 an acre for a fungicide and get the protection they need."

North Carolina Extension Soybean Specialist Jim Dunphy sees another advantage to the early production system, on top of potential drought avoidance.

"Some farmers will see potential hurricane avoidance as as much of a benefit as potential drought avoidance," he says. "These Group IV soybeans are going to be ready in August. When they are ready, it's time to get the combine out, or they will shatter. Growers who plant early will have to scout for stinkbugs in July. That's probably something they are not accustomed to with full season soybeans."

Times changing Some Southeastern farmers have tried the early soybean production system in the past without much success. But Dunphy points out that the Group IV soybeans that were available 10 years ago were bred for the Midwest and not for the Southeast. There are now several Group IV soybeans bred for and adapted to the South.

"This is not for everyone," Dunphy says. "But, if a grower is planning to plant full season soybeans he might as well get started in April, when it's too cool to plant cotton."