RE: Grass and weeds in my clover
S. Texas; try 78% N2. If the atmosphere was 97% Nitrogen you would be dead. Nitrogen fixation with legumes is carried out by rhizobium bacteria.
Red clover can fix approx. 80 lb of nitrogen per acre per year. So if you didn' t harvst the clover crop you should have enough nitrogen for the oats.
Dan O.