The following steps are also explained in the following video: https://youtu.be/PZ7Lvsux1y8
1- Dig up several clusters of tillers with root and soil from multiple locations in the field;
2- Identify and select three to four primary tillers from each cluster – usually the largest tillers with the thickest stem;
3- Strip away and remove all the leaves that are below the lowest visible node, exposing the lower half of the stem;
4- Now look for the presence of two nodes – one should be between 1.5 and 3 inches from the base of the stem and the other should be about 4 - 6 inches above the base of the stem. These nodes are usually seen as clearly swollen areas of a distinctly different (darker) shade of green than the rest of the stem. Note: the upper node may be hidden by the leaf sheath – you may have to run your fingers up the stem to feel for it: if only one node is present, then your wheat is still at Feekes growth stage 6.
5- After locating the two nodes, count the number of leaves that are on or above the bottommost (lowest) node:
5.1. If there are only three leaves at or above the lowest node, then your wheat is at Feekes growth stage 7.
5.2. If there are three leaves fully emerged and the tip of the fourth leaf (the flag leaf) is beginning to emerge or less than half way out, then your wheat is at Feekes growth stage 8.
Click on the following link for information on management practices that are recommended (or not recommended) at these growth stages: http://ohioline.osu.edu/agf-fact/pdf/0126.pdf.