Alnus viridis, commonly known as green alder or mountain alder, is a species of shrub or small tree in the birch family Betulaceae. It is native to the cooler regions of the Northern Hemisphere, including North America, Europe, and Asia.
The green alder typically grows to a height of 2-6 meters (6.5-20 feet) and has a spreading habit. It has glossy, dark green leaves that are round to oval in shape and have toothed margins. The leaves are alternate and grow to about 4-10 cm (1.5-4 inches) long.
The green alder blooms from March to May with pendulous, cylindrical, yellow-green catkins that are 2-7 cm (0.8-2.8 inches) long. The female catkins mature into small, woody cones that contain small, winged seeds.
Green alder is commonly found in wetlands, along streams and rivers, and in other damp areas. It is known for its ability to fix nitrogen in the soil, which makes it a valuable plant for reforestation and land reclamation projects.
In addition to its ecological importance, green alder has traditional medicinal uses as an astringent and anti-inflammatory agent. It has also been used for dyeing and tanning leather.
Overall, the green alder is a hardy and important species in many ecosystems, providing ecological and economic benefits.