THE EFFECTS OF SEPARATED COW SLURRY LIQUOR ON SOIL AND HERBAGE NITROGEN IN PHALARIS-ARUNDINACEA AND LOLIUM-PERENNE

Simulated swards of reed canary grass (Phalaris arundinacea L.) and ry egrass received applications of separated cow slurry liquor in winter, at rates up to the equivalent of 500 m(3)ha(-1). Subsequent measureme nt of oxidized nitrogen in the soil under the different species indica ted that lower levels of soluble forms of nitrogen were found under th e reed canary grass than were under the ryegrass sward. At the first h arvest after liquor application, the dry weight yield of reed canary g rass responded positively to increasing applications of slurry liquor, but the ryegrass sward appeared to be damaged by very high rates of a pplication. At later harvests, yields of the two species were similar, but over the season, apparent recovery of the nitrogen applied to the swards was greater in the reed canary grass than in ryegrass, suggest ing that this species could be of value in the control of losses of nu trients from livestock wastes.