On March 16 and 17, we visited our wheat trials in Clark County and Pickaway County. Both locations were at Feekes growth stage 5 (leaf sheath erect). In northwest Ohio, wheat is at green-up to Feekes growth stage 4.
Generally, Feekes growth stage 6 occurs in southern Ohio during early April; however, with abnormally warm temperatures, Feekes growth stage 6 (jointing) may occur sooner. To evaluate wheat for growth stage 6 follow these steps:
1- Pull, or better yet, dig up, several clusters of tillers with roots 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, but size can be deceiving;
3- Strip away and remove all the lower leaves (usually small and yellowish or dead leaves), exposing the base of the stem;
4- Now look for the first node generally between 1 and 2 inches above the base of the stem. This node is usually seen as a slightly swollen area of a slightly different (darker) shade of green than the rest of the stem.
For a video on identifying Feekes growth stage 6, see this video: https://www.youtube.com/watch?v=iukwznx4DPk
Growth stage 6 signals the beginning of stem elongation. Nitrogen should be applied by this time to maximize yield. This is also the growth stage when some herbicides can no longer be applied. For instance, herbicides such as 2,4-D, Banvel, or MCPA should not be applied after Feekes growth stage 6, as these materials can be translocated into the developing spike, causing sterility or distortion. Huskie and products containing tribenuron and thifensulfuron can be applied through Feekes stage 8, and bromoxynil can be applied until stage 9. Keep in mind that the tribenuron/thifensulfuron-containing products such as Harmony Xtra should generally be mixed with dicamba, 2,4-D or MCPA to broaden the spectrum of control, which affects how late they can be applied. The chart on page 151 of the 2016 Weed Control Guide provides a snapshot of growth stage information.
You should also begin scouting for early season diseases such as Septoria and powdery mildew. However, we do not recommend foliar fungicide application this early in the season. Although some producers may be interested in tank-mixing foliar fungicides with nitrogen or herbicides, our data shows that under conditions in Ohio fungicide applications at or before jointing do not provide adequate protection of the flag leaf and the heads.