How to do a plant count

May 31, 2012 - Issue 14

Hoops or metre sticks are simple tools for plant counts. With the flag marker or GPS, you can return to the same spots through the season to see if all plants survive.

When scouting, take time to check the plant stand. Look for blank areas and also look for thin areas. The plant stand may be adequate in these thinner areas or thinner rows, but a little digging may provide clues on how to improve the drill or whatever else may have caused the problem. Taking these steps this year will help improve establishment in a drier year when mistakes will have a much larger impact on establishment. Sample good areas and bad areas to compare.

How to calculate plant populations:

By length of row. Use a metre stick and count the seedlings per metre of row. Take that number and multiply by 100 then divide by the seed row spacing in cm to get plants per square metre. For example, 25 plants per metre multiplied by 100 then divided by 25 cm (10” row spacing) is 100 plants per square metre. (Divide by 10 if you want plants per square foot.) Repeat.

Using hoops: To do counts, use a hoop with an inside diameter of 56 cm. This is equivalent to 0.25 of a square metre. Count the number of plants inside the hoop, and multiply by 4 to get plants per square metre. (Divide the number of plants per square metre by 10 if you want a rough estimate of plants per square foot.) Repeat.

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