As wheat planting wraps up, it is time to start assessing your plant population or stand that has emerged. As a reminder, please certify your winter wheat planted acres by November 15 at your local USDA-FSA office. Just like corn and soybeans, assessing your initial early season plant population is critical to ensure you have enough plants to optimize yield potential for the growing season ahead. If you missed my two previous topics on wheat (winter wheat variety selection and planting recommendations), you can read them at local agronomic website croptechcafe.org.
Plant population assessment starts in the fall after emergence and then again in the early spring after wheat comes out of winter dormancy. Last season assessing wheat stand was critical as many fields did not have sufficient stands for our desired yield potential and to suppress weeds. Evaluating your wheat stand and determining how many plants you have on a per acre basis is something most growers find difficult and time consuming compared to corn and soybeans. It is normal to use a tape measure to help count plants for corn and soybeans, but it is not as ideal for wheat. To aid agronomists and farmers in eastern Nebraska I developed a process to assess wheat plant populations given our higher yield potential expectations and opportunities to terminate the wheat as a cover crop if the stand is less than adequate. I will review this process in the next paragraphs. Alternatively, you can access a printable handout and watch a YouTube video at https://croptechcafe.org/winterwheat.
To make a PVC grid for 1/10,000 of an acre for evaluating wheat stands you will need the following supplies: One 10 ft piece of ½ inch PVC and four PVC elbows for ½ inch pipe, a measuring tape, a saw, and a permanent marker. You will then need to measure, cut and assemble the grid based on your drill row spacing. Dimensions to cut PVC pipe for each row spacing are as follows: 7.5-inch row spacing is 22.5” wide (across 3 rows) and 28” long (length of row), 8-inch row spacing is 24” wide and 26” long, and 10-inch row spacing is 30” wide and 21” long. Assemble the four cut PVC sections using the four PVC elbows. Lastly, as an example for the PVC grid for 7.5-inch row spacing, I like to add 3 lines with a tape measure and permanent marker that are 7.5 inches apart on two sides of the grid that are 22.5” wide.
Once you have created the 1/10,000 of an acre PVC grid, you can count the number of plants for the three rows inside the grid this fall or early next spring in several different areas of the field and then average those values. I prefer to use a tally counter (find at sports store) to count plants in the grid and record each count on my phone or in a pocket notebook. The interpretations for the 1/10,000 of an acre grid method for winter wheat in eastern Nebraska are the following:
- 49 plants or less (49 x 10,000 = 490,000 plants/acres) – Poor or too thin, likely due to high variability in the stand counts, consider redrilling if prior to November 15 or use as a cover crop,
- 50 to 64 plants – Minimum average, can be adequate with good tillering and weed control,
- 65 to 94 plants – Very good average, can obtain max yield potential in most situations
- 95 plants or more – Excellent or ideal average for maximum yield potential.
For more information about assessing your winter wheat stand and other general inquiries about agronomic resources from Nebraska Extension, feel free to contact me at or 402-821-1722. Know your crop, know your tech, know your bottom line at croptechcafe.org.