Video: Scouting Sessions: Assessing Nodulation in Field Peas
Field pea root nodules form as early as two weeks after emergence, but the best time to assess nodules is at the 10 to 12th
node stages or R1 (flower bud) to capture peak nodulation.
- Dig out the root system of 5-10 plants from 2-3 representative areas of the field.
- Soak roots in water if dealing with clay soils that may strip off nodules.
- Follow the nodule scorecard, rating plant growth and vigour, nodule colour and number, and nodule position. Cut nodules open to assess the colour. If they
are pinkish-red inside, that means they are actively fixing N. Brown, white or green nodules are considered inactive.
- Check the nodules on a few extra plants if you are finding wide variation across the field.
- If your field scores less than 6, further investigation is required to determine if a rescue N treatment is needed.