Remove invasive plants
As development pushes into the Sonoran Desert, an unintended consequence has been the introduction and spread of invasive plants into natural area open spaces (NAOS). The ecological damage caused by this unwanted vegetation negatively impacts the desert landscape by:
- Replacing native plants
- Damaging the ecosystem by displacing native plants
- Eliminating preferred plants for forage
- Creating fuel for fire and promote the spread of fires
- Altering water flow patterns
All these elements can permanently alter the landscape of our Sonoran Desert. Invasive plants upset the sensitive and natural ecological balance of the surrounding area, are a fire hazard and can also disrupt the habitat for desert wildlife.
Get more information about NAOS in this brochure. (pdf)
What is an Invasive Plant?
An invasive plant is generally not native to the Sonoran Desert. These plants compete with native plants and could take over an area. Invasive plants upset the sensitive and natural ecological balance of the surrounding area and can also disrupt the habitat for desert wildlife. In addition to the impact on native plants, this vegetation becomes a major fire fuel source during the hot weather when these weeds dry out.
How Can You Help?
- Learn to identify problem plants
- Remove invasive plants from private property
- Work with your landscaper/gardener so native plants take priority in your yard
- Report infestations in common areas to your homeowner association board
- Add these plants to your homeowner association’s prohibited plant lists
- Learn about proper eradication methods
- Join a recognized volunteer weed removal group, get trained and participate
- Ask the nursery where you buy landscape materials to stop carrying these plants
- Help the Fire Department by providing a defensible space on the portions of your property that are nearest to structures and adjacent to natural Sonoran Desert areas
Residents are urged to contact Solid Waste at 480-312-5600 for more information or before any large clean-up or landscaping projects. Scottsdale will remove brush trimmings from residential properties for small clean-up projects on developed land only. Vegetation from washes, community common areas, undeveloped lots, and large projects is not the responsibility of city crews.
Desert Broom (Baccharis sarothroides)
native — This native desert shrub, that is almost always green, grows quickly to nearly 10-feet high. In autumn, the blooms, containing a mass of seeds with white bristles, easily become airborne and spread freely. Desert Broom is viewed as an invasive plant because of its aggressiveness in overtaking disturbed areas (such as roadsides and new landscaped areas), and because it burns fiercely and is a significant threat to nearby structures.
Red Bromegrass (Bromus rubens)
non-native — Found in very dense patches or widely dispersed as individual plants, the Red Bromegrass is a fast-growing, annual grass that reaches over 10-inches tall. Characteristic brush-like heads start out green in color, become reddish purple when mature and then light brown when seeds dry. The seed carrying portion of the grass have sharp ends and easily attach to animals or clothing for transport to other locations where the seeds then germinate. Red Bromegrass has become a major threat to the Sonoran Desert because it is so well established.
Buffel Grass (Pennisetum ciliare)
non-native — This perennial bunchgrass grows up to 4-feet tall and has a mass of long, tough roots that can grow to 8-feet deep. Narrow, light green leaves are 1 to 4-inches long. Bristly flower heads may be purple, gray or yellowish and turn a distinctive golden-brown when dry. Buffelgrass will burn while still green. When native plants die, Buffelgrass moves in and chokes out native seedlings.
Tamarisk/Salt Cedar (Tamarix spp.)
non-native — This shrubby tree grows up to 15-feet with gray-green foliage and slender branches. Pink-white flowers appear from January to October. Tamarisk spreads rapidly and forms dense thickets. Once established, it is difficult to eradicate. These trees use large amounts of ground water causing desert springs to dry up and crowding out native trees such as cottonwood, mesquite and desert willow. Because this plant is difficult to remove, it is advised to contact a specialist if you detect a Tamarisk in your area or in the Preserve.
Fountain Grass (Pennisetum setaceum)
non-native — This perennial bunchgrass grows up to 3-feet high and has long, slender green leaves and purple to white feathery spikes. Fountain Grass is a highly aggressive, fire - adapted species that crowds out native plants and spreads quickly. Fountain Grass has been used in landscaping. Native ornamental grasses should be used instead of Fountain Grass. Alternatives: Purple Threeawn, Arizona Cotton Top or Bull Grass.
Malta Starthistle (Centaurea melitensis)
non-native — This erect, winter annual grows up to 2-feet tall and in dense stands. It has grayish-green foliage and yellow, thistle-like flowers with sharp spines of a purplish or brown color that appear in May and June. Malta Starthistle aggressively competes for space with native species and reduces wildlife habitat and food.
Saharan Mustard (Brassica tournefortii)
non-native — This annual, spring herb forms rosettes 6- to 12-inches in diameter. Leaves vary in size and have tiny bristles on the undersides. Small pale-yellow flowers appear from January to April or May. Tiny reddish seeds are formed in narrow pods. Saharan Mustard can grow in large stands, creating barriers to normal wildlife movement when plants are alive. As desert temperatures rise, parts of the plant die and increase wildfire fuel loads dramatically.
Bermuda Grass (Cynodon dactylon)
non-native — This perennial grass is common to many lawns in southern regions and grows well in our hot, desert climate. It is the most common summer lawn choice in the desert southwest. Bermuda Grass competes with native plants and invades disturbed areas. It is a leading cause of hay fever in the Sonoran Desert.
Globe Chamomile (Oncosiphon piluliferum)
non-native — Globe Chamomile sprouts and grows vegetatively from late November until the end of January. It begins to flower in early January and quickly begins seed setting by early February. The seeds are very light and easily transported by wind and vehicle traffic. In years of sufficient winter moisture, Globe Chamomile can go through up to three generations between November and the end of April, resulting in a prodigious production of plants and seeds in a short period of time. It is easily recognized by its dark green "carrot like" leaves and unique rounded flowers. The leaves have a pungent odor!
To control the spread of this weed, removal must take place before plants go to seed. If infestations are allowed to propagate over the course of several seasons, they will form dense stands with prolific seed production. In residential areas Globe Chamomile can be manually dug out as soon as it is recognized. It is important to remove the plants before they develop mature seeds.