Peas work together with the rhyzobium in the inoculant (which is applied to the seed at planting) to fix their own nitrogen. All legumes are capable of this sybiotic relationship if the correct organisms are present. On our field tours, we found most of the plants we analyzed had adequate nodulation from the inoculant. A nodule will be pink in color if it is functioning properly. There were fields with fewer nodules, and it seemed that they were ones where more nitrogen was available without the peas having to work for it. For instance: last year's dry-land corn fields with crop failures...
To check your field for nodulation, dig up a plant and submerse the roots in a bucket of water. Gently rub off the soil and you should be able to see the inoculant at work!
