Seeds absorb oxygen and water. Root structures begin to emerge from the seed. Temperatures between 54- and 77-degrees Fahrenheit are optimal for germination. Seed treatments such as fungicides and insecticides can help manage early diseases.
Emergence happens when the cotyledon appears above the ground. The first leaf has started growing. Three leaves need to fully develop before tillering starts. The root system expands, and the crown begins to form at the base of the main stem. Scouting is suggested for proper emergence with targeted stand at 15-25 plants per square foot. Adequate phosphorus is critical during early Feekes 1-3 to promote rooting and tiller formation.
Tillering initiation starts during this stage. Tillers are initially encased in a protective structure called the prophyll. In winter wheat, tillers formed in the fall usually contribute more to grain yield than spring tillers. During this stage, the crown root system starts to develop. In a dual-purpose system, grazing should be started at this stage after crown roots are developed.
Primary tillers continue to develop in the axils of the first four or more true leaves. The first one to three primary tillers are the most productive tillers and may comprise as much as half of total yield. Secondary tillers can develop from the base of primary tillers. The crown root development system increases extensively. Between 5-15 percent of total dry matter is accumulated. Scout for insects and weeds. Treat with a herbicide application as needed to reduce weed competition. In thin stands, early nitrogen applications can be made at Feekes growth stage 2-3 to enhance tillering. Fall nitrogen application of 20-30 lb/acre is sufficient for developing fall tillers. Excess nitrogen at this time can stimulate excess vegetative growth and make the plant more susceptible to winter kill, fungal diseases, and insect damage.
Gradually lowering air temperatures and shorter days induce the winter hardiness in winter wheat. Vernalization, or winter dormancy, requires three to eight weeks of temperatures below 50 degrees Fahrenheit.
Leaf stems begin to grow, and the pseudo-stem becomes erect. In winter wheat, spring green-up begins. The pseudo-stem is when a secondary leaf sheath wraps around a primary one. This stage is an ideal time to make spring nitrogen applications on winter wheat.
The pseudo-stem should be strongly erect at this stage along with leaf sheaths elongated. The developing head is pushed into the pseudo-stem. The potential number of spikelets is determined during this stage. Stress during this stage can reduce total number of kernels per head. The first hollow stem also appears during this stage. The plant is using about 0.1 inch of water per day. Feekes 5 is a good time to apply additional nitrogen if split applying. Tillers developing after this time are not expected to contribute to yield. If grazing, cattle should be removed before the first hollow stem is grown.
This stage is also referred to as “jointing” as rapid stem elongation begins. Progression from one growth stage to the next is occurring rapidly. The first stem node is visible during this stage as a result of internode elongation. The plant becomes more sensitive to lower temperatures and the developing head is pushed up the expanding stem. The plant is using about 0.25 inches of water per day. During this stage, consider applying a first round of fungicide application if the crop is under disease pressure. It is not recommended to apply 2,4-D or dicamba once this stage is reached.
At this stage, the second node and the second to last leaf should be visible. Water intake and nutrient demand increases and temperatures below 24 degrees Fahrenheit can harm the plant.
The last growing leaf (known as the “flag leaf”) is visible and begins to grow above the third to fourth node. This is a prime growing stage for the plant with increasing water demand. Scouting is suggested for diseases and pests to help maintain optimal leaf growth. The flag leaf is critically important to yield and will contribute 50-75% of the photosynthesis contributing to developing grain. Damage to this leaf should be prevented.
The flag leaf is completely visible from the main stem of the plant. From this point on, the plant’s energy is used to develop reproductive tissue and fill grain. During this stage, consider applying a fungicide to protect the flag leaf if foliar diseases are present on the lower canopy. Nitrogen application after this time can increase grain protein levels but will likely have little effect on yield.
The wheat head is inside the leaf sheath giving the plant a swollen appearance (boot stage). During this stage, the flag leaf sheath and peduncle (the stem supporting the head) grow, and the developing head is pushed through the flag leaf sheath. Scouting for insects and diseases is suggested.
During the heading stage, the heads grow past the flag leaf sheath. All the heads should be out by Feekes 10.5. This growth stage takes between 3-5 days. Temperatures below 30 degrees Fahrenheit can harm the plant. A fungicide application could be considered during this stage to help protect the flag leaf and heads.
Flowering or anthesis will occur during these growth stages. Feekes 10.5.3 occurs when flowering is complete at the base. The number of flowers pollinated determines the number of kernels per head. The wheat is extremely sensitive to temperature during this stage.
The kernels are watery ripe during this stage. They are established about 10 days after flowering. A clear liquid can be squeezed out of the kernels.
The kernels are milky ripe at this stage (milk stage). The solid content in the endosperm increases. This stage is about 15-18 days after flowering. A milk-like fluid can be squeezed out of the kernel.
This stage is mealy ripe, a soft dough-like starch accumulates in the kernel (soft dough stage). The green color begins to fade, kernels are soft but dry.
The kernels are hardening, and the moisture decreases 40-30 percent (hard dough stage). They reach peak dry matter weight and are physiologically mature. Monitoring the moisture of the crop is critical at this stage. Scout for any pests such as wheat head armyworms.
At this stage the kernels are ripe, and moisture decreases from 30 to 15 percent. Green plant tissue becomes straw. Harvest is suggested when kernels reach 15 percent moisture to avoid losses in grain quality.