In our urban forest lives a curiosity, the sweet gum tree (Liquidambar styraciflua), which continues this month to bombard streets with spiky burs long after most other deciduous trees have shed last year’s production.
It’s a sure bet you’re encountering them on walks. You can view one on the Boulevard at Irving Avenue.
The tree’s name is derived from its resinous sap, which was sometimes chewed like gum. Sweet gums can grow to 75 feet tall, and were widely planted in the last century to replace elms decimated by Dutch elm disease. The gumball-shaped pods contain seeds that are provender for birds such as goldfinches and chickadees. This crop is, however, not so highly valued by humans irked by its litter.
Assets? Yes. The star-shaped leaves provide spectacular fiery late-autumn displays. The tree’s shikimic acid is used in Tamiflu, a drug to treat bird flu. The pods are used by crafters to create door wreaths, and by gardeners as spiky mulch to protect young plants.
Betsy Shea-Taylor
