C partitioning with varying belowground resource availability and found that trees of three species (Eucalyptus spp., P. radiata, and P. taeda) partitioned less C belowground with increased fertilization and irrigation. Information is lacking with regard to the effects of growth selection on biomass and C partitioning, particularly for mature trees. In a seedling study, Johnsen and Seiler (1996) found that northern provenances of P. mariana allocated more biomass to roots than southern sources.