The presence of flavonoid aglycones in bud ex cretions has been stressed and they have been stud ied in great detail by one of us in the 1970s. Exu date flavonoids were reported for members of the genera Aesculus (Hippocastanaceae, ), for Alnus, Betula, and Ostrya (Betulaceae, see ), for Populus (Salicaceae; see e.g.  and ref. therein), for Prunus (Rosaceae, ), and for Rhamnus (Rhamnaceae, ). Some more recent results were reported and concerned rare flavonoid aglycones in Betula nigra , phenolic triglycerides in Popu lus lasiocarpa , cinnamic acid derivatives in Populus nigra , and a stilbene in Alnus viridis , In the course of these studies, several minor prod ucts remained unidentified, due to paucity of ma terial and/or lack of markers. After isolation by preparative TLC, some of these have been identi fied by direct comparisons with authentic samples; one structure was elucidated by NM R analysis.