A sustainability condition for stochastic forest model

A stochastic forest model of young and old age class trees is studied. First, we prove existence, uniqueness and boundedness of global nonne-gative solutions. Second, we investigate asymptotic behavior of solutions by giving a sufficient condition for sustainability of the forest. Under this condi-tion, we show existence of a Borel invariant measure. Third, we present several sufficient conditions for decline of the forest. Finally, we give some numerical examples.