Shoestring Acacia, Acacia stenophylla, combines two qualities that are rare among popular desert landscape trees: columnar (upright growth) structure and evergreen foliage. This Australian native was introduced to the desert southwest decades ago but gained wide popularity only in the last 10 to 15 years. Shoestring Acacia is reasonably fast growing maturing to a height of 20 to 40 feet with a 15 to 20 foot spread. The trees are moderately drought tolerant but cannot be naturalized to subsist on the annual rainfall in the desert southwest. Shoestring Acacia grows well in full sun or partial shade and is cold hardy to about 20 F. In Australia, where it is used as lumber and a food source for Aborigines, it is found growing at the edges of rivers and will tolerate periodic flooding and heavy clay soils. The tendency to grow along streams may explain two of its Australian common names, Native Willow and River Cooba (Cooba is the Australian common name for Acacia salicina). Best growth is achieved in well drained soil and regular deep irrigation.

Cream to yellow colored, ball-shaped flowers, in small clusters, (3 to 6 flowers/cluster) occur throughout the year with the majority produced in spring. Flowers mature rapidly to pods that resemble a string of pale green beads with pods constricted between each seed. Leaves (or phyllodes) are long and narrow approximately 1/4 to 1/2" wide and up to 12" long. Leaves are pale grayish green and are generally straight but can be slightly curved or twisted. Stenophyllas do produce some leaf, flower and pod litter.

The bark of maturing trees is rough, deeply textured and dark brown giving it a sharp contrast to the gray-green foliage. The columnar shape of the tree is the result of its weepy branches and leaves that hang down parallel to the upright main trunk(s). The narrow leaves are fairly dispersed giving the canopy a transparent, lacy quality that produces filtered shade. Its unique structure and open canopy allows Shoestring Acacias to be used in a variety of landscape applications. They are used in screen planting around the perimeter of properties or along streets or sidewalks. They are also used near or against taller structures to add color and graceful silhouettes to large walls. The filtered shade allows most flowering shrubs planted underneath Shoestrings to grow and flower normally. The columnar structure makes them ideal for planting in narrow or tight landscape settings. Trees can also be planted in small clusters or groupings without encountering tangled branches.

Trees may produce suckers if roots are exposed to the sun or disturbed. If not pruned these suckers will form clumps of trunks that may or may not be desirable. Small trees, 15 gallon and 24" box, are not striking and do not often reflect the ultimate shape and character of this specie. In desert landscape designs Shoestring Acacias are among the most versatile and well adapted trees for a wide assortment of landscape uses. They require limited pruning and to date have no reported serious insect or disease pests.