MAESTRO 1 data from the Flevoland test site in the Netherlands have be
en used for this study. From a complementary ground data collection, t
he bole volumes of a large number of stands of mainly poplar and ash h
ave been estimated. The relationships between radar backscattering and
bole volumes have been examined experimentally and theoretically. In
the case studied, the radar backscattering sensitivity to bole volumes
increases as the wavelengths increase, and is highest at P band. The
sensitivity of the radar backscattering to variations of forest canopy
components and moisture contents has been investigated theoretically
at P band. It is important to obtain information on such variations be
fore the inversion problem can be solved. The present study indicates
a potential for bole volume determination by P-band SAR.