Standing Crop and Pattern in Pure Stands of Mercurialis Perennis and Rubus fruticosus in Mixed Deciduous Woodland

Standing crop of Mercurialis perennis L. shoots was measured by dimension analysis, a technique not previously used in herb production studies. It is accurate, and allows several measurements to be made on the same material. Maximum standing crop (970?244 kg ha--) occurred in May, after maximum shoot density, and thereafter fell linearly until September. Above-ground biomass of Rubus fruticosus in May was assessed by harvesting, and sub-dividing the material into separate year classes. Standing crop was 749 kg ha-l. Weights of standing dead and litter were each almost as high. Two year old canes were each about five times the weight of one year old canes; total weight of canes in these classes was similar. Pattern of shoot distribution in M. perennis and cane distribution in R. fruticosus was examined. Through time, shoot distribution in M. perennis altered from aggregated towards randomness, indicating death in areas of high shoot density. All cohorts of canes in R. fruticosus were extremely clumped. The results are explained for both species in terms of patterns of morphology and growth.