Photos: © Bill Hubick and Dan Small, Maryland Diversity Project

September’s Mystery Plant is a native multiple-trunked shrub that grows 5-20′ tall along wetland margins. The smooth grayish trunks lack conspicuous lenticels. Younger twigs are light green and pubescent. The alternating obovate or broadly elliptic leaves measure 2-5″ by 1-3″ with finely serrated and slightly wavy margins. The lower leaf surfaces are glabrous to sparsely pubescent, usually along the central vein. Leaf venation is pinnate with 8 or more pairs of straight veins. The fruits are catkins: the males elongating dramatically in the spring and the females persisting in winter, making it easy to ID to genus at least.

It is…

Botanical Name: Alnus serrulata
Common Name: smooth alder,
Family: Betulaceae
Habitat: shores of rivers or lakes, swamps, wetland margins

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