Many very enthusiastic and energetic students from the Clackamas Academy of Industrial Science joined us last week at Goat Island to plant 20 Alnus rubra (Red Alder) trees. Students learned that Red Alder are a “pioneer” tree species that can grow in soil that lacks nutrients as their roots contain a bacteria that fixes atmospheric nitrogen into the soil.
From the USDA Forest Service:
The ability of red alder to fix atmospheric nitrogen can result in increases in both nitrogen content and its availability in the soil. Nitrogen fixed in the nodules is added to the soil in four ways: direct excretion from living roots or nodules, decomposition of dead roots or nodules, leaching from foliage, and decomposition of litter rich in nitrogen.
Students didn’t stop there! After recent flooding of the nearby Clackamas River, Goat Island had a lot of litter carried in and students spent some time cleaning up. Thank you CAIS!!