Invasive species threaten Arizona's land and water. What to know about keeping them away

Yahoo

01-03-2025

Think the yellow sprinkling of flora alongside Interstate 17 is a testament to a beautiful blooming spring?
Or the increase of bass near Lake Powell is good for recreational fishing?
Think again.
These plants and animals are environmental blights for Arizona.
The importance of invasive species mitigation and prevention is the focus of National Invasive Species Awareness Week, an observance meant to raise awareness about the species, the threat that they pose, as well as prevention tactics to slow their spread throughout the world. A multiagency gathering introduced invasive species management initiatives and helped professionals to network with leaders in the field.
Here's what can you do all year long here in Arizona:
Invasive species are plants or wildlife that outcompete native wildlife, destroy local habitats and can throw ecosystems out of balance.
Threats to wildlife include increased competition, predation, introduction of diseases and parasites, hybridization. Threats to landscapes include degradation of the environment and decreased biodiversity.
Invasive species in Arizona alter ecosystem balance and reduce biodiversity by outcompeting native plants, reducing the resources wildlife rely on and creating a cascading effect of lessened resources. Some invasive species grow rapidly, and then quickly dry out in the Arizona heat, increasing the risk of wildland fires.
There are eight invasive plants and grasses that top the invasive species watch list, according to Arizona State Parks and Trails:
Stinknet is a fast-growing plant that outcompetes native plants for resources. Originally from South Africa, this aggressive plant has rapidly spread across the desert landscape, displacing native vegetation and impacting the ecosystem. It's noticeable by a distinctive odor, especially after rainfall, and is able to propagate quickly due to its signature yellow flowers that produce hundreds of seeds at a time.
Salt cedar, or tamarisk, is found along waterways and riparian areas. It was introduced for erosion control and ornamental purposes, but its rapid growth displaced native vegetation. It is able to thrive in saline soils and withstand drought conditions, which gives it the ability to outcompete native plants for resources and negatively impact water availability and quality, as it consumes large amounts of water and increases soil salinity due to the salt content of the leaves.
Buffelgrass is a native of Africa, Asia and the Middle East, introduced for soil stabilization and livestock forage in the Sonoran Desert. Buffelgrass was able to quickly dominate vast areas, including desert washes, hillsides, and open spaces. The grass is a fire risk, as it ignites easily and burns intensely, threatening both human communities and native plant species.
Fountain grass is a quickly spreading invasive grass that thrives in arid and semi-arid regions. Primarily used as an ornamental plant, fountain grass spreads rapidly, displacing native vegetation throughout Arizona. Its seeding, rapid growth rate and ability to thrive in diverse environmental conditions contribute to its aggressive spread.
Malta starthistle hails from the Mediterranean region and was likely introduced to Arizona inadvertently through contaminated seeds or agricultural activities. The highly flammable plant poses a significant threat to native plant communities and ecosystems due to its aggressive spreading behavior and density, degrading grazing lands and native habitat.
Scotch thistle is a native to Europe and Asia that has become a spreading invasive species in Arizona, particularly near disturbed areas — where the ground cover is destroyed or removed, leaving the land subject to accelerated erosion — roadsides, and rangelands.
Yellow bluestem is a native species from Asia that was introduced for forage and erosion control in desert and grassland areas. Its ability to thrive in various soil types and climates allows it to establish in a wide range of habitats, including disturbed areas, roadsides and rangelands.
Red brome is a highly invasive species native to Europe that has become one of the most problematic invasive grasses in the state. This high fire-risk plant thrives in disturbed areas, such as roadsides, fields, and overgrazed rangelands, where it outcompetes native vegetation for resources.
Fighting the problem: Cold water shots into the Colorado River slow a bass invasion in the Grand Canyon
Quagga mussels are currently at the top of invasive species watch lists. The mussels have acted as little hitchhikers, spreading from the Great Lakes to the western U.S. via recreational boats. They pollute the shoreline, damage equipment and infrastructure, and alter the aquatic food web in Arizona by promoting algae growth.
Bullfrogs, crayfish and bass found in the Grand Canyon area are some of the aquatic animal species that have impacted native Arizona aquatic ecosystems.
Other invasive species in Arizona include insects such as bark beetles that impact local forests; the Asian giant, or "murder," hornet; algae that alters water quality; and native aquatic plants that form monocultures.
For aquatic invasion:
If you are launching a boat at a local marina, the advisory is to only do so after draining the water and scrubbing the underside to avoid bringing species along for the (boat) ride.
To ward against invasive species such as quagga mussels, for example, the Arizona Game and Fish Department's Don't Move a Mussel campaign provides guidelines for boaters to prevent the spread of aquatic invaders:
1. Clean: Remove mud, plants and animals from every part of your boat, trailer, anchor, lines and equipment to prevent harboring mussels.
2. Drain: Pull your drain plug every time you take your watercraft out of the water to eliminate all water, including livewells and ballast.
3. Dry: Allow your boat and equipment to thoroughly dry before launching in other waters. Dry time may vary depending on humidity and temperature.
For more information and to find a professional decontaminator, visit azgfd.gov/ais.
For land invasion:
First, when spotting an invasive species, use manual removal or herbicide application. Make sure to pull the entire weed, including the roots, enclose it in a bag, and throw the plant away.
When selecting landscaping for your own home, opt for native, drought-resistant plants. This cuts down on resource competition when using plants suited for the environment.
Consider volunteering with public education campaigns to learn more about invasive species ecological impact and how to prevent further expansion in the Sonoran Desert ecosystem:
Verde River Cooperative Invasive Plant Management Plan, led by Friends of the Verde River, provides a strategic approach for controlling invasive plants in the Verde River Watershed, while increasing community and stakeholder engagement.
Arizona Department of Forestry and Fire Management Invasive Plant Grant Program provides funding by the state of Arizona and the U.S. Forest Service to treat invasive plant infestations that threaten forested, woodland or rangeland areas.
Arizona Department of Agriculture Noxious Weed List is the official state list of invasive species that are known to aggressively spread and cause ecological and/or economic impacts. The list includes both species known to exist in Arizona and those that are problematic elsewhere.
AZGFD State of Arizona Aquatic Invasive Species Management Plan is a statewide strategy to halt the spread and eliminate aquatic invasive species from becoming further established in Arizona waters.
Arizona-Sonora Desert Museum's Save Our Saguaros.
Catalina State Park Buffel Slayers.
Central Arizona Conservation Alliance, or CAZCA's, programs: Sonoran Insiders — a social media ambassador program designed to link local influencers with conservation nonprofits and land managers; Desert Defenders — a collaborative, community science program focused on finding, mapping and removing invasive species at local parks and preserves; Sonoran Seed Collaborative — a native plant project dedicated to restoring parks and preserves; Urban Desertscape Enhancement — a collaborative group focused on educating homeowners on the importance of water conservation and native plant landscaping.
The goal is to minimize occurrences of invasive species statewide through educational campaigns, public awareness and involvement, and the use of state/national park programs.
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This article originally appeared on Arizona Republic: How invasive species can damage land, water resources in Arizona