Evaluating Winter Wheat Plant Stands

Winter wheat is one of the few crops that provide a second opportunity to assess the crop in spring and replant to another crop if winter survival is not acceptable. Assess the wheat crop during April and early May. Leave the replant decision as late as possible to accurately determine plant stand and plant health.

Table 1. Determining Yield Potential for Various Plant Stand Counts
Number of Plants
% Yield
Potential
Planting Date
per metre of row per foot of row Yield t/ha (bu/acre)
Oct. 5 Oct. 15
66
201
100
5.34 (80)
4.84 (72)
33
10
95
5.11 (76)
4.57 (68)
23
7
902
4.84 (72)
4.37 (65)
20
6
85
4.57 (68)
4.10 (61)
16
5
80
4.30 (64)
3.90 (58)

Source: Smid, Ridgetown College, University of Guelph, 1986-90.

1 Full stand.
2 23 plants/m (7 plants/ft) of row, healthy and evenly distributed, will still achieve 90% of yield potential and does not require replanting. A field with an average of 23 plants/m (7 plants/ft) of row without relatively uniform distribution, or with plants severely damaged by heaving and other injury factors, will not yield satisfactorily. Consider replanting in this case.

Damaged plants will often recover under good weather conditions, while plants that are expected to recover may die if hot dry conditions exist. The table above indicates yield potential for various plant stand counts. The planting date will have an impact on the replant decision.

The video below demonstrates the process of evaluating winter wheat stands in the spring.