Phosphorus applications (0.6, 1.2 and 1.8 gm/kg soil) were applied to six leguminous tree species; Acacia laeta, Acacia abida, Acacia nilotica, Acacia farnesiana, Tamarindus indica and Haematoxylum campechianum to define the suitable P rate for favorable growth. The heaviest roots in average of both seasons; fresh and dry were obtained from T. indica. The thickest and heaviest shoot were resulted from A. laeta. The longest roots recorded by A. nilotica and A. farnesiana. The maximum N and P contents were obtained by T. indica. The other species achieved intermediate levels of N and P. In relation to P application, a rate of 1.2 gm/kg of phosphorus was the best for shoot diameter and root
length, meanwhile, 1.8 gm/kg increased fresh and dry weight of both shoots and roots. Leaf content of N was increased with increasing P from 0.6 to 1.8 gm/kg.
Phosphorus addition at 1.2 gm/kg was more effective in accumulation of P concentration.