Silk tree, also known as mimosa, or silky acacia, is a small to
medium-sized tree that can grow up to 20-40 feet tall. The bark is
light brown, nearly smooth, and generally thin with lens shaped
areas along the stem. The attractive fern-like leaves of mimosa are
finely divided, 5-8 inches long by about 3-4 inches wide, and
alternate along the stems. Silk tree has showy and fragrant pink
flowers, about 1½ inches long, that resemble pom-poms and are
arranged in panicles at the ends of branches. Fruits are flat,
straw-colored pods about 6 inches long containing light brown
oval-shaped seeds about ½ inch in length. Pods ripen in August to
September and begin to disintegrate soon after, but remain on the
trees into winter.
Because silk tree can grow in a variety of soils, produce large
seed crops, and resprout when damaged, it is a strong competitor to
native trees and shrubs in open areas or forest edges. Dense stands
of mimosa severely reduce the sunlight and nutrients available for
other plants.
Silk tree takes advantage of disturbed areas, often spreading by
seed from nearby ornamentals or from contaminated fill dirt. It
prefers full sun and is often seen along roadsides and open vacant
lots in urban/suburban areas. Silk tree can tolerate partial shade
but is seldom found in forests with full canopy cover, or at higher
elevations (above 900 m or 3,000 ft), where cold hardiness is a
limiting factor. It can, however, become a serious problem along
riparian areas, where it becomes established along scoured shores
and where its seeds are easily transported in water. Like many
successful exotics, it is capable of growing in a wide range of
soil conditions.
Silk tree was introduced to the U.S. in 1745. Silk tree
continues to be a popular ornamental because of its fragrant and
showy flowers.
The cache itself is well camoed, just like another of my latest
caches, so Happy hunting!