Experiments were performed in a greenhouse to evaluate the effect of natural nodulation in the development of Pacara Earpod Tree (Enterolobium contorsiliquum) and Leucaena (Leucaena leucocephala) is soil with different uses in Tocantins. We used three soil samples of woods, cultivated areas four and in a degraded area, in pots in a completely randomized design with four replications. In both species nodulation was observed in all soils studies areas with better nodulation occurring in soil cultivation, providing a higher accumulation of biomass. Soil from the degraded area the two species showed nodule number and biomass of nodules significant, with potential for use in disturbed areas, with characteristics of degraded soils.