Again does the clover fix enough nitrogen to suffice the needs of the oats and peas and is it probably causing grass and weed growth.
an average of 40 to 200 lbs of nitrogen per acre is adeed to the soil by legume bacteria annually if the crop in plowed under. Clover fix more nitrogen than to large seeded legumes.
On the other hand legumes are more efficient in the fixation of N on soils with low rather than high N content. It wuld be normal to grow legume crops previous to crop requirening large amounts of N.
Food for thought