Silk tree

Albizia julibrissin

This week’s tree of the week is a medium sized specimen of silk tree spreading dappled shade over the side yard of a house on Homer St. just off Van Zandt Ave.  This species is in full glory during the heat of summer, as it thrives in warm dry urban conditions.  Its native range is the arid regions of central Asia from the Iran to China.  While looking for this week’s tree I came across many Albizia planted in small front yards arching vase shaped branches out over the street.  The tree is named, silk tree, after the clusters of pink stamens that are thin, fine, and soft like strands of silk.  

Also frequently known as Mimosa, as visually it appears very close to the tropical species of that name.  That name is frowned upon by botanists as the two species are not even closely related as both are classified in different families.  Like true Mimosa, Albizia has a sensitive response, folding up its compound leaves every night and reopening them every morning to collect sunlight.

Even though considered hardy for RI the tree does suffer in the cold with many trees exhibiting die-back every winter.  In RI that isn’t necessarily a bad thing as the tree does have a robust seed set most years.  In warmer parts of the country it has escaped cultivation and is considered invasive.  I do see seedlings here in disturbed urban sites, but not yet growing in natural areas.