abstract volatile constituents of california skullcap (scutellaria californica a. gray) flowers were isolated by solid-phase microextraction (spme) and analyzed by gc and gc/ms. a total of 52 constituents were identified (constituting 90.8% of the total area), 12 of which were tentatively identified. -caryophyllene (56.6%), germacrene d (6.9%), methyl 2-methylbutyrate (4.9%), -bourbonene (4.5%), -humulene (2.8%), methyl butyrate (2.7%), and -copaene (1.5%) were the major constituents of the flower volatiles. due to their low odor thresholds (measured in water) and fruity aroma, methyl 2-methylbutyrate (4.9%; odor threshold = 0.1 ppb) and ethyl 2-methylbutyrate (0.7%; odor threshold = 0.007 ppb) were considered to be important contributors to the characteristic sweet, apple-like odor of these flowers. key word index: scutellaria californica lamiaceaeheadspace volatiles-caryophylleneodor threshold