Savvy Can Keep Desert Broom in Check
                                                                by Nan Byrne

The Valley's urban population sprawl is swelling, and our Sonoran Desert is shrinking. Man's alterations and the desert's responsive changes are bringing consequences that must be heeded. The precariously balanced Arizona Uplands ecology is beginning to seriously tilt and, without common-sense intervention can become irrevocably altered and erased. The equilibrium of the environment deserves priority consideration.

It's important for everyone to cultivate desert savvy, to have personal awareness, information and knowledge. Desert savvy addresses the source of detrimental consequences and takes responsible actions to avoid them.

Desert savvy is presently needed to check the over proliferation of a desert plant whose natural ecological constraints are being changed by desert development.

This noticeable native shrub, Baccaharis sarothroides or desert broom, is taking full advantage of cleared and disturbed soil, where it can best promote its built-in opportunism.

Desert broom has broom-like stems and late-blooming habits. An evergreen shrub during most of the year, it is identified by its yellow-green color and branching structure. Instead of a central trunk, multiple strong stems sprout from the root, like straw switches in a broom. These early green branches, appearing almost leafless, help perform photosynthesis.

Dependent upon the limitation or abundance of water supply, a mature plant can be more rounded and dense at 3 to 4 feet or woody and scraggly at a maximum height of 9 to 12 feet.

In common with the jojoba bush, broom is dioecious, which means male and female flowers are borne on separate plants and cross-pollinate. Only the female flower bears fruit. In November and December, the female shrub is most lovely--and most obnoxious--as it exercises two survival strategies assuring species continuation: it blooms later than most of the competition and it blooms bounteously, producing a super-saturation of fruits.

The cottony mounds crowning the female plant are composed of countless individual fruits. Each seed is attached to multiple silken, white hairs called pappus. The pappus, serving as transport parachutes, lift in the breezes and carry the seeds drifting to the ground, collecting everywhere! This saturation technique of dispersal is designed to increase the odds for suitable bedding sites, where the seeds will wait for the winter rains to trigger germination.

Within nature's interconnective system of checks and balances, broom functions as the pioneer, providing a first line of early revegetation and erosion control to disturbed drainages, sandy washes, old animal burrows and burn sites.

In the desert wilderness, broom's takeover habit is held in check because the undisturbed desert floor patina, with its intact plant communities, resists germination. An additional check is that broom, in contrast to many other desert plants, is relatively short-lived. Under normal circumstances, individuals die back, terminating seed production in roughly 10 to 15 years. However, large self-perpetuating colonies can persist for perhaps 100 years before disappearing naturally.

Because of its rapidly increasing invasive growth into man-modified areas it is obvious that desert broom's traditional checks and balances are dysfunctional. Without "savvy" intervention, broom can crowd and overgrow road shoulders, obstructing vision. It will successfully compete with and eventually crowd out more desirable plants, native or introduced, especially if a water source is reliable. Tenaciously weed-like, it will infiltrate a cleared yard or garden in unkempt mounds. The female plants' volumes of yearly pappus can spell misery to allergy sufferers. And the "cotton" drifts are a messy nuisance at doorways and in garages, outlying buildings and pools.

Broom probably doesn't provide significant food or browse for wildlife, although it might give some shelter. It flunks as a nurse plant, but it readily grows in other plants for nurse protection, especially buckhorn cholla and prickly pear.

In optimum conditions, without constraints, it thrives, rapidly multiplies and overpopulates an area. Ten, fifteen, one hundred years is too long a wait for nature to move it along.

Once established in ill-favored locations, mature plants are difficult and labor-intensive to remove. Cutting off the branches at ground level is but a temporary solution. Survival-adapted, new branches will sprout profusely from the corm. Removal of or irrevocable damage to the root system seems to be required. Except for some pre-emergents, acids and poisons kill more than broom and are to be avoided.

Prevention is the savvy first line of defense. Retain the indigenous vegetation as an unmolested natural buffer by clearing it judiciously, disturbing only the necessary minimum area of ground.

The second-best approach for broom control is to pull the young sprouts out with the roots, best timed for easier pulling after a good, earth-softening rain.

Applied desert savvy will avoid destroying another native shrub that as a young sprout can be mistaken for desert broom. This shrub, the turpentine bush, has less-obtrusive adult habits, making it a better neighbor.

Desert savvy can be applied to all facets of man's interaction with the environment of this desert place. A savvy stewardship offers an in-the-present, positive path to assure the future continuance of a balanced, desirable, healthy habitat for all desert dwellers-be they two-legged, four-legged, no-legged, winged or rooted!