Smooth alder (Alnus serrulata), also known as tag alder, is a dense shrub found in and around wet areas such as bogs, drainage ditches, streambanks, and the shoreline of ponds and lakes. It often grows in dense thickets but can also be found as two or three stems in scattered localities.
Smooth alder is a member of the birch family and is one of the earliest blooming species found in our area. It starts flowering here in mid-February and is easily recognizable by the long yellow catkins that hang from the branch tips. Catkins are a type of inflorescence that are long and contain hundreds of individual flowers. In the case of smooth alder, the first catkins to appear are male and contain pollen bearing stamens. The female catkins are shorter than the male catkins and mature at the time the male flowers are producing pollen. Wind pollinates the flowers. Male and female catkins are typically borne on the same plant.
|Male catkins (large), female catkins (small) and last year's fruits.|
Smooth alder is found throughout eastern North America, as far north as the St. Lawrence River and as far south as Florida. It prefers loamy and clay soils that may or may not be nutrient rich and has the ability to fix nitrogen in the soil.
There are records of smooth alder being used for medicinal purposes. Historically it is one of those plants that was recognized in folk remedies as a purification plant which could perform multiple tasks and cure the "winter blahs." It has been used in the treatment of diarrhea and other internal ailments. Externally it has been used from everything from hives to hemorrhoids.
The wood is thin and brittle and has no commercial value, but it is valued as an erosion control plant because of its extensive root system. It is well suited for stabilizing shorelines along rivers and lakes and is often planted for that purpose.
You may have been driving down the road or strolling along a creekside or lakeside trail and encountered this shrub before and asked yourself what is that plant with those odd, yellow things hanging off of it. Now you know the answer.
Until next time!