A series of experiments will be conducted to investigate the apparent suppressive effect of incorporated crimson clover (Trifolium incarnatum L.) residue on the growth of lambsquarters (Chenopodium album L.) in a corn (Zea mays L.) cropping system. Measurements of above and below ground plant parts will document specific effects of a crimson clover nitrogen source on the growth, development, and nitrogen uptake of sweet corn and lambsquarters, grown in pure and mixed cultures. Companion growth chamber and field studies will examine emergence and time to emergence of both species under a regime of clover-derived nitrogen. Is low nitrogen availability responsible for previously observed suppressive effects on emergence? A field study will test for interactive effects of crimson clover residue and ammonium nitrate addition on lambsquarters growth and nitrogen uptake after emergence. The results of these studies will aid in the effective management of legumes in cropping systems and provide insight on how temporal availability of resources affects patterns of consumption and growth and, ultimately, outcomes of competitive interactions between plants.
