A nutrient solution containing essential macro (excluding mineral N) and micronutrients was mixed into the sand before seeding of subterranean clover and ryegrass, or the transplanting of capeweed seedlings; 5 atom% [sup.
Capeweed shoots were separated into leaf, stem, and flower head (seed was removed).
15]N mineralisation of root residue N also continued over this period with an additional 5% of clover and 2% of capeweed root [sup.
15]N mineralisation of root residues was estimated to be 10%, 7%, and 7%, respectively, for clover, capeweed and ryegrass (Table 5).
15]N for shoot residues were 93%, 92%, and 102%, respectively, for subterranean clover, capeweed, and annual ryegrass (Table 4).
15]N mineralisation occurred from both the capeweed and ryegrass shoots despite a large difference in the C to N ratio (Table 6).
6%) for subterranean clover than for capeweed or ryegrass.