CARBON, NITROGEN, PHOSPHORUS AND SULPHUR IN HERBAGE PLANT ROOTS

C. N, P and S were determined in the roots of white- and red-clover, lucerne, perennial ryegrass, cocksfoot and timothy, taken at intervals over a period of several months, and in roots of ryegrass receiving four levels of fertilizer N. The results indicated that decomposition of The root material would result in The mineralization of N in substantial amounts from white clover, in smaller amounts from red clover and in negligible amounts from lucerne. The roots of grasses would tend to immobilize soil N, even when They bad received moderate applications of fertilizer N. The C:P ratios suggested that the legume roots would neither mineralize nor immobilize inorganic pbospbate but that the grass roots would induce immobilization. S was likely to be mineralized in appreciable amounts from roots of white– and red–clover, but not firom roots of lucerne or the grasses.