Most barley fields in the county have been harvested with reports of good yields this year. Good yields can be attributed to optimal planting dates in the fall, lack of heavy rainfall during the winter, and good conditions during spring growth. Double cropped soybean plantings after barley have been delayed due to lack of moisture in the ground which can result in uneven seeding depth and uneven emergence. Rainfall has come to certain parts of the county and planting has resumed in those parts. Wheat harvested will be in full swing this week as conditions allow. A couple of factors come into play for double cropped soybeans:
*Early planted soybeans have the advantage of increased canopy biomass, greater number of main-stem nodes, earlier flowering, and increased crop growth rates during pod set.
* Late planted soybeans will have a shorter vegetative growth stage before initating the reproductive stage. This happens because soybeans are day length sensitive and as days become shorter, reproduction stage is triggered within the plant. Flowering can start after only one or two nodes develop. This results in less canopy mass and a shorter plant.
*A 15″ row planter or drills are recommended for double crop plantings to help achieve row closure quickly and increase light interception and biomass accumulation.
*Seeding rates should be increased to 165,000-180,000 seeds per acre for middle June and 175,000-200,000 for late June. Seeding depth should be between .75 -1.5″. Adjust the planter or drill to go through heavy straw residue and achieve accurate seeding depth, good seed to soil contact, and good furrow close. Drills may require a higher seeding rate to achieve desired seeding rate.
* After June 15th, yield potential starts to drops. By late June/early July, yield potential will decrease (up to 1 bushel/day) so double cropped soybeans should be planted as soon as possible after harvest.
Phillip Sylvester, Extension Agricultural Agent, Kent County, UD.
