A simple model describing herb layer dynamics under the tree canopy wa
s developed to quantify the forage supply of the herb layer to ungulat
es in forests. The basic principle of this forage supply model is that
the herb layer biomass can be described by a logistic curve. The rate
of development and the maximally attainable biomass are assumed to de
pend on the relative light level that reaches the forest floor. Biomas
s growth is derived from functions describing monthly relative growth
rate under open field light conditions in combination with light respo
nse curves.