Besides some common flavonoids, buds of alder-trees produce many rather rare compounds as aglycones. Quercetin 7,3',4'-trimethyl ether had been known before only from buds of Aesculus hippocastanum. The methyl ethers of 6-hydroxykaempferol were first found in Betula ermani and Alnus glutinosa. Quercetin 3,7-dimethyl ether and quercetin 3,3'-dimethyl ether have just been reported to occur together in buds of several Populus species. The flavonoid patterns of the Alnus species described here are all different (see also'). A chemotaxonomic survey on more than one dozen other Alnus species is in preparation.