We apply the characteristic basis function method (CBFM) to compute the electromagnetic fields scattered by three-dimensional dielectric objects in the context of forest scattering simulation. We study the effect of some CBFM parameters on the accuracy of the results, and on the performance of the CBFM when compared to the classical MoM. We show that once the CBFM parameters have been appropriately chosen, this new method realizes a significant reduction both in terms of CPU time and memory use, while maintaining a level of accuracy comparable to that of the conventional MoM. Consequently, the CBFM enables us to handle electrically larger forest simulation scenes than is possible with classical MoM for higher frequencies.