Today managing your wheat crop requires knowledge of the different growth stages of the plant. Growth stage identification is critical for scouting and proper timing of fertilizer and pesticide applications. Each week throughout the rest of the growing season I will discuss the various wheat growth stages I am seeing in our wheat fields and management issues at each stage. This week I will focus on Feekes 3 & 4. Most of our wheat has progressed to the Feekes 4 growth stage.
Winter dormancy – Vernalization.
Gradually lowering temperatures and shortening day length induce winter hardiness in winter wheat. Vernalization requirements range from three to eight weeks of temperatures below 50 degrees Fahrenheit.
Management. Manage stocking density in dual-purpose wheat systems and try to maintain 60 percent canopy coverage.
Feekes 3 – Completion of tillering.
Once requirements are met, the growing point differentiates and the embryonic head reaches the double ridge stage.
Double ridge. The primordia, which differentiate into spikelets, become visible after vernalization requirements are met. Floret initiation starts slightly above the middle portion of the microscopic head and moves outward. The number of florets initiated determines the potential number of kernels per head.
Depending on the season and planting date, some tillering occurs in the spring. Genetic potential and environmental conditions determine the number of tillers on a plant. Tillers with three or more leaves are nutritionally independent from the main stem.
Management. If fewer than 70 tillers per square foot are present, an early nitrogen application can increase spring tillering and help compensate for thin stands. Avoid excess nitrogen.
Feekes 4 – Leaf sheaths lengthen (spring greenup).
Leaf sheaths begin to lengthen. The pseudo-stem, a succession of leaf sheaths wrapped around each other, starts to become erect.
Management. Ideal time to make single spring nitrogen applications based on yield goal. Begin scouting for insects and weeds.