Plant Materials Program “The Plant Materials Program and its cooperators have contributed the bulk of the material and technology now used in ecosystem

restoration and are our foundation for meeting conservation challenges of the future.”

-- D.T. Booth and T.A. Jones, Native Plants Journal

Plant Applications for Addressing 

Invasive Plant Species

Every day invasive plant species are threatening 

the conservation of our nation’s vital agricultural 

and natural resources. Forests and rangelands are 

being contaminated, cropland production is 

significantly reduced, streams and water ways are 

being choked with weeds so they no longer 

function, and wildlife are losing habitat. This is 

just the beginning of the destruction invasive plant 

species exact on our nation’s natural resources if 

they continue to advance. Because invasive 

species are too numerous to list in a brief 

description, they are simply referred to as Invasive 

Plant Species. 

An Effective Counter Assault 

Our best defense against invasive plant species is 

the development of diverse plant communities 

with competitive desirable species capable of 

preventing advancement and replacing the 

invasives when they are controlled. Since 1935, 

the Plant Materials Program has been providing 

solutions to address invasive species. These 

successes are often overshadowed by 

introductions of new invasive species through our 

borders in cargo ships, airplanes and automobiles. 

The traveler is often unaware that they are making 

these introductions. 

Undeterred against these challenges, the Program 

continues to find new technologies to address 

these resource concerns. This new technology is 

developed at the Program’s 27 Plant Materials 

Centers (PMC) across America that select, study 

and release plants and develop planting and 

management 

technologies for 

plant species that 

ultimately can be 

used to help restore 

devastated areas. 

Additionally, Plant 

Material Specialists 

are trained to plan 

appropriate 

conservation 

treatments and 

work with partners 

to address these 

affected areas.

Through the Program’s many studies aimed 

directly at invasive species, they have helped 

develop methods to control or suppress many of 

these plants. Additionally, the Program has found 

appropriate replacements for many invasive plant 

species once they have been controlled. The 

Program has developed management strategies to 

improve established plant communities after 

invasive plants are controlled. 

Highlights of Invasive Species Studies at Plant 

Materials Centers 

Pullman PMC, Pullman, WA 

Yellow starthistle is one of the most noxious and 

tenacious weeds found on over 9.25 million acres 

of rangeland in the western U.S. Plant Materials 

Program researchers are examining the effects of 

native stands of bluebunch wheatgrass on 

invading yellow starthistle. 

Yellow starthistle (Centaurea solstitialis) 

is an invasive weed affecting over 9 

million acres of U.S. rangelands. 

Despite its beauty, purple 

loosestrife (Lythrum salicaria) 

is one of the worst invasive 

plant species. 
The USDA is an equal opportunity provider and employer. 

About Us 

The USDA NRCS Plant Materials Program consists of a 

network of 27 Plant Materials Centers (PMCs) and Plant 

Materials Specialists located throughout the United States. 

For over 70 years, PMCs and Specialists have provided 

essential and effective plant solutions for critical habitats, 

environmental concerns, management practices, and key 

farm and ranch programs. 

For more information, visit: 

http://Plant-Materials.nrcs.usda.gov 

http://www.nrcs.usda.gov 

Helping People Help the Land... 

August 2007 

Cogongrass (Imperata 

cylindrica) is an invasive plant 

species in the Southwest 

Plant Materials Centers in Meeker, CO; 

Aberdeen, ID; and Los Lunas, NM 

Cheatgrass, a winter-annual grass found in all 50 

states, severely alters the ecology of our western 

range and forestlands. PMCs are evaluating native 

plant species adapted to compete with cheatgrass 

in infested areas on range, forest and critical areas. 

Centers also are evaluating the tolerance of 

desirable native plant species to herbicides used to 

control cheatgrass and the use of introduced 

species as a bridge for cheatgrass control and 

eventual long-term establishment of native plant 

communities in cheatgrass-infested areas. 

Plant Materials Centers in Aberdeen, ID; 

Corvallis, OR; Elsberry, MO; Big Flats, 

NY; Beltsville, MD; Pullman, WA; and 

Los Lunas, NM 

Several PMCs throughout the nation are 

evaluating the ability of native species to compete 

with invasive plants in riparian and wetland 

systems. In New York, Oregon, Missouri, New 

Mexico, and Idaho, the Program is evaluating 

several native herbaceous and woody wetland 

species for their ability to compete with some of 

the worst invasives, including purple loosestrife, 

Japanese knotweed, invasive thistle species and 

reed canarygrass. In Missouri and Washington, 

techniques are being developed that will improve 

re-establishment of native plants into areas 

currently infested with reed canarygrass. In 

Maryland, propagation, production and 

establishment methods are being developed for 

native aquatic species to help prevent hydrilla 

invasion and improve aquatic habitat in the 

Chesapeake Bay. 

Plant Materials Centers in Bridger, MT; 

Brooksville, FL; and Los Lunas, NM 

Highly disturbed areas, such as those associated 

with minelands, saline sites, roadsides and highly 

acidic sites, are very susceptible to invasion by 

noxious weeds. Several PMCs are evaluating 

native plants 

which are 

especially 

adapted to these 

difficult sites to 

help prevent 

infestation by 

noxious weeds 

such as 

knapweed 

species, Canada 

thistle and 

cogongrass. 

Other Plant Materials Centers across 

 the country 

All 27 PMCs are developing native plants for a 

variety of conservation uses to combat and replace 

invasive plant species. For example, the 

Booneville (AR) PMC is evaluating methods to 

establish native grasses in existing stands of tall 

fescue to improve pasture quality. The Elsberry 

(MO) PMC is developing native shrub alternatives 

to Amur honeysuckle and autumn olive for 

wildlife, buffer and shelterbelts plantings. In 

addition, the Kika de la Garza (TX) PMC is 

evaluating native grasses to replace buffelgrass on 

rangeland.