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Off-line and on-line supercritical fluid extraction (SFE) coupled with gas chromatography (GC), supercritical fluid chromatography (SFC), and mass spectrometry (MS) have been used to characterize the composition of extracts from the desert botanical species, Dalea spinosa. Off-line SFE conducted at pressures as high as 680 atm yielded odoriferous extracts similar in composition to an isopropyl alcohol-derived extract when the two extracts were characterized by SFC and GC/MS. SFC of the extracts revealed the presence of up to 18 components, GC/MS indicated six major compounds, and headspace GC/MS showed over 20 components. On-line micro-SFE/SFC was performed on single seeds of D. spinosa as well as dissected single seeds over the pressure range of 100-400 arm at 45 degrees C. SFE/SFC on portions of a single seed, such as the calyx or incised resin sac, indicated subtle differences in molecular composition. These results suggest that the resin sac is particularly enriched in many odoriferous compounds.