Words on Wellness: Red Alders
Strong winter storms are reshaping our waterways, leaving fallen trees, small landsides and denuded river banks in their wake. Thankfully, red alders (Alnus rubra) are adapted to such conditions and begin rebuilding new habitat from these open patches. Besides anchoring soil, alders provide large amounts of nitrogen that enrich the soil for other plants to grow in. Like many pioneer species, alder evolved a symbiotic relationship with a nitrogen-fixing bacterium, in this case, Frankia alni. Frankia possesses hemoglobin - the same oxygen-binding compound that we have in our red blood cells. This allows alders to live in standing water and produce up to 280 pounds of nitrogen per acre per year. Then, as their leaves and branches break down, the added nutrients make life possible for trees such as coast redwood.
It is especially in winter, when alders stand tall and bare-limbed, that we notice their silvery outer bark. However, they are named for the inner red bark which oozes a red fluid when first cut. Traditionally, this bark was used in washes to treat poison oak, insect bites, and skin irritations. Bark can be carefully harvested by cutting small twigs and branches, then using a knife to strip off much of the outer bark. This bark must then be dried to use internally as otherwise it can cause vomiting. Dried alder bark was simmered as tea by indigenous peoples to treat stomach complaints, hemorrhoids, diarrhea, internal bleeding and lymph disorders. Recent clinical studies have verified that red alder contains betulin and lupeol, compounds shown to be effective against a variety of tumors and skin cancer. This is in-part due to its strong anti-inflammatory effect.
Alder bark is high in salicin, which converts to salicylic acid (natural aspirin) in the human body. This compound acts to relieve pain and lower fevers. Infusions and tinctures of the bark have been used in the treatment of headaches, rheumatic pains and arthritis. Leaf and bark teas are still used to treat tonsillitis, hemorrhoids, vaginal infections and inflammatory conditions. Externally, a compress or bath with the bark reduces aches and pains. The sap of this slender tree can be applied externally to cuts for help with wound healing. Finally, alder catkins and young cones are astringent and bitter but edible, and have been chewed to treat diarrhea.