USDA 

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United States Department ofAgriculture 

Field Guide for Managing

Buffelgrass in the Southwest 

Forest Southwestern 

Service Region TP-R3-16-03 Revised June 2017 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Cover Photos 

Upper left: Buffelgrass clump – Travis Bean, Univ. Arizona 

Upper right: Buffelgrass collar with hairs – Southern Arizona Buffelgrass Coordination Center, buffelgrass.org 

Lower left: Buffelgrass infestation – USDI National Park Service 

Lower right: Buffelgrass inflorescences – Southern Arizona Buffelgrass Coordination Center, buffelgrass.org 

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Buffelgrass (Cenchrus ciliaris L., synonym: Pennisetum ciliare L.) 

Grass family (Poaceae), Paniceae tribe 

Buffelgrass is an introduced forage grass that has become 

invasive in southwestern States. Due to its threat to the 

Sonoran Desert ecosystem, buffelgrass has been listed as a 

noxious weed in Arizona. 

This field guide serves as the U.S. Forest Service’s 

recommendations for management of invasive buffelgrass 

in forests, woodlands, rangeland, desert, and desert scrub 

associated with its Southwestern Region. The 

Southwestern Region covers Arizona and New Mexico, 

which together have 11 national forests. The Region also 

administers 4 national grasslands that are located in 

northeastern New Mexico, western Oklahoma and the 

Texaspanhandle. 

Description 

Buffelgrass (synonyms: anjangrass, African foxtail grass, 

zacate buffel) is a drought-tolerant bunchgrass originally 

from African savannah that wasintroduced into the U.S. 

for forage and erosion control. However, many of the traits 

that make buffelgrass desirable as a forage grass also 

cause it to be highly invasive in native plant communities. 

Buffelgrass has a number of cultivars and is variably 

classified across two very closely related grass genera – 

Cenchrus and Pennisetum. Key characteristics useful for 

buffelgrass identification include a bottlebrush-like 

inflorescence and light-colored hairs that occur near the 

junction (collar) where leaves meet the stem. Buffelgrass 

is similar in appearance to fountain grass (Cenchrus 

setaceus, syn. Pennisetum setaceum), which is an escaped 

ornamental grass. However, buffelgrass is generally 

shorter (1 to 1.5 feet tall) than fountain grass (3 to 4 feet) 

and has shorter, thicker inflorescences (1.5 to 5 inches 

long) compared to fountain grass (4 to 14 inches). 

Growth Characteristics 

• Tussock-forming perennial grass; typically 1 to 1.5 

feet in height but can grow to over 3 feet. Knotty and 

branching at base; tillers often have secondary 

branching that give plants a subshrub-like 

(chaemaphytic) appearance. 

• Normally warm season and intolerant to cold 

temperatures but at lower elevations can grow in 

moderate temperatures during winter after rainfall. 

Shade tolerant; shade may promote growth on some 

sites. Generally requires summer moisture to thrive. 

• Rapid growth; germinates from seed, matures, and 

flowers within 6 weeks after rainfall of at least 0.75 

inches and a period of moist soil lasting 3–5 days. 

• Flat leaf blades (3–12 inches long, 0.1–0.3 inches 

wide), scabrous or with long, soft hairs; sheaths open, 

keeled, glabrous to having sparse, long, soft hairs; 

collar region with sparse, whitish, straight hairs about 

0.2 inches long. 

• Purplish to reddish, bottlebrush-like inflorescences 

(0.8–5.1 inches long); spikelets in clusters of 2–4, each 

with 2 flowers (lower floret reduced); spikelets tan, 

beige, or slightly orange at maturity; spikelets fall off 

whole from the rachis. 

• Reproduces from apomictic (asexually formed) seed; 

seed usually lies dormant 3 to 18 months and is viable 

for at least 3–5 years. 

Ecology 

Impacts/Threats 

Although buffelgrass is used as forage for livestock, it is 

an unwanted weedy invader in many arid regions of the 

world. Buffelgrass is a particularly serious threat to the 

Sonoran Desert in Arizona and the lower Rio Grande 

Valley in Texas. It can out-compete native vegetation for 

soil nutrients and moisture. In addition, infestations of 

buffelgrass alter fire regimes in native plant communities 

by changing fire frequency and intensity through an 

increase in fuel loading and connectivity. Buffelgrass regrows quickly following wildfire; however, fire can kill or 

injure nearly all native plant species in Sonoran Desert 

communities. As a result, buffelgrass has the potential to 

displace native plant communities and change ecologically 

rich areas into near-monocultures of buffelgrass with 

decreased diversity, cover, and densities of native plants. 

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Site/Distribution 

Buffelgrass is spread widely across disturbed and 

undisturbed areas in the Southwest, which includes urban 

areas, roadsides, rangeland, old fields, and desert plant 

communities. It is commonly found on rocky, south-facing 

slopes in Arizona uplands. The species has been planted as 

a forage grass on re-seeded rangeland in certain parts of 

Texas and Mexico. 

Spread 

Seed is spread by wind, water, animals, and vehicles. 

Whenever buffelgrass becomes established near roads and 

ditches, the opportunity for spread is increased. 

Invasive Features 

Buffelgrass spreads aggressively by seed and grows in 

dense stands that can double in cover every 2–3 years. The 

species is highly adaptable and grows on many soil types 

including soils that are heavy, sandy, or overlying 

limestone. It is often more effective at capturing soil 

moisture than native plant species, thereby contributing to 

its invasiveness. 

Management 

Buffelgrass is a major threat across large areas of the 

Southwest, particularly in the Sonoran Desert and lower 

Rio Grande Valley. To undertake effective buffelgrass 

control at this scale, collaboration among affected 

stakeholders is essential, especially stakeholders managing 

pathways (road systems, utility corridors, etc.) by which 

buffelgrass can invade. A major emphasis for stakeholders 

should be to reduce buffelgrass fuel loads and connectivity 

thereby diminishing the likelihood of wildfire. Another 

management emphasis should be to maintain or restore the 

resiliency of native plant communities. Indications of 

treatment success during restoration include the return of 

native plant species and an increase in species diversity. 

Long-term planning, integrated management, and followup monitoring are necessary to control buffelgrass 

effectively. The following actions should be considered 

when developing a management approach for buffelgrass: 

1. Develop a specific action plan to meet goals and 

objectives for infested areas, which may include 

eradicating new buffelgrass infestations in sensitive 

sites or controlling buffelgrass in managed 

landscapes, e.g., wildland-urban interface (WUI) 

areas. 

2. Evaluate infested sites to determine which treatment 

methods (or combination of methods) are most 

effective for buffelgrass control. Chosen methods 

should focus on stopping seed production and 

mitigating impacts from fire. A combination of 

various treatment methods and repeated treatment 

will often improve effectiveness. 

3. Give priority to early detection of buffelgrass and 

eradication of new infestations in otherwise healthy 

sites. For established infestations, the perimeter and 

any satellite populations should be treated first to 

prevent further encroachment. 

4. After treatment, implement monitoring and followup treatment for missed plants and seedlings. To 

deplete the buffelgrass seed bank, treatments need to 

be repeated annually for several years and can be 

repeated within a growing season if rainfall causes 

regrowth and green-up. Also, monitor recovery of 

desirable native plants following control efforts. 

5. Limit disturbance and maintain healthy plant 

communities that can help prevent or limit new 

infestations. This may involve using improved 

grazing management practices to prevent excessive 

grazing and/or reseeding areas with desirable native 

grasses and forbs after disturbance. 

6. Detect, report, and map buffelgrass populations that 

have spread out over large areas. Also map presence 

and condition of native vegetation. Keep annual 

records of reported infestations. Identify priority 

areas for treatment by using records, maps, and other 

information sources such as known habitat for 

Threatened & Endangered species, travel corridors, 

seed pathways, etc. 

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Table 1. Management options* 

Site Physical Control Cultural Control Biological Control Chemical Control 

Wildland- Use hand pulling, grubbing, or hoeing Avoid using buffelgrass for None available Use backpack or hand-held 

urban on small patches but minimize soil erosion control. sprayers for small patches. 

interface 

(WUI) 

areas 

disturbance. Remove the entire root 

mass to prevent re-sprouting. Transport 

removed buffelgrass in plastic bags to a 

sanitary landfill or leave plants onsite 

by using the “pile-and-rock” method or 

by spreading plants over disturbed soil 

and placing rocks over them. 

Revisit treated sites to remove new 

buffelgrass seedlings and previously 

missed plants. 

For disturbed areas with 

supplemental irrigation or 

adequate moisture for 

germination, consider 

reseeding with native 

species. Avoid undue soil 

disturbance. 

Broadcast spraying with 

vehicles may be used for 

larger patches. Special 

Note: Protect non-target 

plants from spray drift, 

runoff, or residue 

movement in soil plants. 

Revisit treated sites to spray 

new seedlings, missed 

plants, and regrowth on 

previously sprayed plants. 

Roadsides Mowing or grading along roadsides 

should be used with caution to prevent 

seed spread. Cut buffelgrass before seed 

stalks are developed. 

Use hand pulling, grubbing, or hoeing 

on small patches but minimize soil 

disturbance. Remove the entire root 

mass to prevent re-sprouting. Transport 

removed buffelgrass in plastic bags to a 

sanitary landfill or leave plants outside 

of the right-of-way by using the “pileand-rock” method. 

Revisit treated sites to remove new 

buffelgrass seedlings and previously 

missed plants. 

Avoid using buffelgrass for 

erosion control. 

Implement sanitary 

requirements for vehicle 

operations in buffelgrassinfested areas and require 

new infestations along 

roadsides to be reported. 

Gravel and other road 

materials transported into 

un-infested areas should be 

free of buffelgrass seed. 

Consider reseeding 

disturbed roadsides with 

native species during periods 

of adequate moisture. Avoid 

undue soil disturbance. 

None available Use ground spraying with 

backpack sprayers, ATVs, 

trucks, or tractor-towed 

equipment. Wash 

underneath vehicles after 

spraying to prevent spread. 

Revisit treated sites to spray 

new seedlings, missed 

plants, and regrowth on 

previously sprayed plants. 

Rangeland Use hand pulling, grubbing, or hoeing 

on small patches but minimize soil 

disturbance. Remove the entire root 

mass to prevent re-sprouting. Transport 

removed buffelgrass in plastic bags to a 

sanitary landfill or leave plants onsite 

by using the “pile-and-rock” method or 

by spreading plants over disturbed soil 

and placing rocks over them. 

Revisit treated sites to remove new 

Avoid using buffelgrass for 

erosion control. 

Consider reseeding 

disturbed areas with native 

species during periods of 

adequate moisture. Avoid 

undue soil disturbance. 

Avoid moving livestock 

through infested areas. 

Consider using 

prescribed grazing as 

part of an integrated 

management 

approach. 

Use backpack spraying, 

ground broadcast spraying, 

or aerial spraying depending 

on accessibility of infested 

areas. Wash underneath 

ground equipment after 

spraying to prevent spread. 

Revisit treated sites to spray 

new seedlings, missed 

plants, and regrowth on 

buffelgrass seedlings and previously 

missed plants. 

Inspect and remove attached 

inflorescences and seed from 

clothing, livestock, and 

vehicle surfaces before 

moving to un-infested areas. 

previously sprayed plants. 

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Table 1. Management options* (cont.) 

Site Physical Control Cultural Control Biological Control Chemical Control 

Wilderness Use hand pulling, grubbing, or hoeing Avoid using buffelgrass Consider using Use backpack sprayers for 

and other on small patches but minimize soil for erosion control. prescribed grazing as small infestations. 

natural 

areas 

disturbance. Remove the entire root 

mass to prevent re-sprouting. 

Transport removed buffelgrass in 

plastic bags to a sanitary landfill or 

leave plants onsite by using the “pileand-rock” method or by spreading 

Consider reseeding disturbed 

areas with native species 

during periods of adequate 

moisture. Avoid undue soil 

disturbance. 

part of an integrated 

management 

approach. 

Broadcast spraying by 

aerial or ground methods 

may be used on larger 

stands if permitted. Wash 

underneath ground 

equipment after spraying 

plants over disturbed soil and placing Avoid moving livestock to prevent spread. 

rocks over them. through infested areas. Revisit treated sites to 

Revisit treated sites to remove new Inspect and remove attached spray new seedlings, 

buffelgrass seedlings and previously inflorescences and seed from missed plants, and 

missed plants. clothing, pets, and livestock regrowth on previously 

before moving to un-infested sprayed plants. 

areas. 

Post signs warning visitors to 

inspect and remove attached 

inflorescences and seed from 

clothing, pets, and livestock 

when leaving an infested 

area. 

* Choice of a particular management option must be in compliance with existing regulations for the land resource. 

Table 1 summarizes some management options for 

controlling buffelgrass in various situations. Further 

details on these management options are explained below. 

Choice of individual control method(s) depends on many 

local factors including the extent and density of 

buffelgrass infestation, current land use, and site 

conditions (terrain, accessibility, microclimate, presence of 

flora and fauna, etc.). Other important considerations 

include treatment effectiveness, overall cost, and amount 

of time needed to achieve control. More than one control 

method may be needed for a particular site. 

Physical Control 

Physical methods usually have to be repeated and must 

often be timed properly to be effective. Both manual and 

mechanical methods of buffelgrass removal may facilitate 

further invasion through soil disturbance, erosion, or seed 

spread. To help reduce buffelgrass establishment, soil 

disturbance should be kept to a minimum. 

Manual Methods 

Hand-pulling, grubbing, or digging – Mature buffelgrass has 

a tough root crown and a dense, fibrous root mass that 

makes manual removal difficult. Hand-pulling, grubbing, 

and hoeing buffelgrass are effective (but demanding) 

methods for control. Hand removal is easiest when the soil 

is moist, temperatures are cool, and plants are in their early 

growth stage. Simple digging tools (digging bar, hoe, 

shovel, Pulaski tool, etc.) may be used to aid root removal. 

Regardless of method, the root crown must be completely 

removed. To prevent seed dispersal, removed plants should 

be placed in plastic bags, which can then be taken to a 

sanitary landfill for disposal. In areas too remote to transport 

plastic bags, removed buffelgrass plants may be left onsite 

by (1) putting the plants into a pile and then placing rocks 

over them, i.e., pile-and-rock, or (2) spreading the plants out 

over the disturbed soil and then placing rocks over them to 

hold them in place. With the latter method, the removed 

buffelgrass plants should be distributed in a thatched pattern 

by layering the plants in rows with the lower part of each 

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plant and its roots left exposed. The rows should be 

oriented such that the tops of plants are pointed upslope. 

At the topmost layer, the inflorescences should have rocks 

placed over them as an anchor. The shading effect of this 

method will help prevent buffelgrass seeds from 

germinating. Sites undergoing buffelgrass removal should 

be revisited after rainfall, and any missed plants or newly 

emerged seedlings should be pulled up or spot sprayed. 

Several consecutive years of hand removal may be 

required to eliminate an infestation completely. 

Mechanical Methods 

If using machinery to manage buffelgrass, equipment 

and clothing should be cleaned after use to prevent 

movement of seed into un-infested areas. 

Tillage – Properly timed and repeated tillage with a 

plow or disc may be used to reduce buffelgrass in 

cropland or pasture areas; however, tillage when used 

alone as a treatment may actually increase buffelgrass 

establishment under certain conditions. Tillage is most 

effective during hot, dry weather that greatly stresses 

plants, although soil moisture must be adequate for 

tillage. Tillage will exhaust carbohydrate reserves 

stored in roots but will not eradicate seeds. Therefore, 

tillage should probably be combined with herbicide 

control in most cases. 

Mowing and grading – Mowing or grading with heavy 

equipment may suppress buffelgrass growth and seed 

production. However, these treatments often favor reestablishment and increased dominance. In general, 

mowing should be discouraged as a standalone method 

since buffelgrass can set seed at low heights. 

When mowing or grading, buffelgrass should be cut 

before seed stalks are developed. Herbicide application 

or hand-grubbing should be used as follow-up 

treatments, particularly after significant rainfall. Dense 

buffelgrass stands in accessible areas such as graded 

roadsides can be mowed to stimulate growth and ensure 

that all plants are at a similar growth stage prior to 

herbicide treatment. Allow at least 25% of the original 

plant height or foliage to recover from mowing before 

spraying. In certain situations, mowing buffelgrass 2 to 

4 weeks before herbicide application has been shown to 

be an effective sequence for control. Use vehicle or 

trailer-mounted sprayers to apply herbicide during 

active growth, as indicated by the appearance of shiny, 

bright green leaves. 

Prescribed Fire 

Fire is generally not recommended as a control method 

for buffelgrass. The species re-grows quickly after fire, 

and buffelgrass stands may return at greater densities 

than before. In addition, most native vegetation in the 

Sonoran Desert is not fire-adapted. However, a strategy 

of prescribed fire-herbicide-reseeding is currently being 

researched for restoration of highly disturbed areas such 

as abandoned agricultural fields. 

Cultural Control 

Buffelgrass seed should not be planted for forage or 

erosion control. Areas disturbed by fire, road 

construction, overgrazing, etc., may be reseeded with 

native species to help prevent buffelgrass 

encroachment. In southern Arizona, native species 

adapted to lower elevations such as Arizona cottontop 

(Digitaria californica), plains bristlegrass (Setaria 

macrostachya), sideoats grama (Bouteloua 

curtipendula), and sprucetop grama (B. chondrosioides) 

may be used. However, soil disturbance associated with 

reseeding may actually encourage emergence of 

buffelgrass seedlings. 

Various sanitary measures may be implemented as part 

of an overall management program to prevent 

buffelgrass spread. Gravel and other road materials 

transported into un-infested areas should be free of 

buffelgrass seed. Livestock should not be moved 

through infested areas if possible. Inspect and remove 

attached inflorescences and seed from animal hides, 

clothing, and vehicle surfaces before moving from 

infested areas to un-infested areas. Signs may be posted 

in sensitive areas to warn visitors to remove attached 

inflorescences and seed from clothing, vehicles, 

livestock, and pets after leaving an infested area. 

To manage buffelgrass on a landscape scale, landowning stakeholders and the public must be educated 

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about buffelgrass and its impacts. The media should be used 

when possible to focus public attention on prevention, early 

detection, and long-term commitment to buffelgrass removal. 

Citizen volunteer groups may be enlisted to monitor and 

manually remove buffelgrass from residential neighborhoods 

and along roadways. Collaboration among diverse 

stakeholders should also be encouraged. In southern Arizona, 

various agencies and organizations regularly collaborate on 

buffelgrass management, including the hosting of 

community events such as Beat Back Buffelgrass Day to 

remove the invasive grass from roadsides and sensitive areas. 

In regions where buffelgrass is an integral part of the 

livestock industry, culturally sensitive collaboration may be 

necessary to prevent buffelgrass from spreading beyond 

areas where it is used as forage. 

Biological Control 

Grazing 

Buffelgrass is moderately palatable to livestock as a forage 

grass, and livestock grazing of buffelgrass may play a role 

in reducing fuel loads and wildfire threats. However, 

grazing alone will not control buffelgrass and should only 

be used for buffelgrass management as part of an 

integrated management approach. Intensive grazing may 

be used to stimulate plant growth prior to herbicide 

application during the actively growing stage. Monitor 

sites previously grazed and treated after substantial warm 

season rains and provide follow-up treatment by hand 

pulling or spot spraying emergent seedlings. 

Research shows that buffelgrass seed does not germinate 

after passing through the rumen of cattle thereby 

precluding buffelgrass establishment from seed in manure. 

The same inability for seed to germinate after digestion 

may apply to other ruminants (sheep and goats). However, 

inflorescences and seed on livestock hides should be 

removed before moving them from infested areas to uninfested areas. 

Classical Biological Control 

Classical biological control involves the beneficial action 

of introducing insects, parasites, or pathogens to manage 

pests and mitigate their damage. A spittlebug (Aeneolamia 

albofasciata), leaf spot (Cochliobolus australiensis), and 

fungal blight (Magnaporthe grisea) have the potential to 

injure buffelgrass stands. This grass reproduces 

vegetatively or asexually and has low genetic diversity, 

which suggests that it is unlikely to develop natural 

resistance to leaf spot or blight. However, no classical 

biocontrol agent has been approved by the USDA for use 

against buffelgrass. 

Chemical Control 

The primary herbicides used to control buffelgrass are 

glyphosate and imazapyr (table 2). These broad spectrum 

chemicals are non-selective and will impact non-target 

species. This includes most woody and broadleaf species; 

however, imazapyr is typically more active against woody 

species than glyphosate. Herbicides selective for grass 

species (e.g., clethodim or fluazifop) are generally 

ineffective against established buffelgrass plants, but they 

will kill seedlings. 

Glyphosate and imazapyr have many trade names. These 

products are often formulated differently and have unique 

requirements and restrictions. Thus, it is very important to 

read the herbicide label carefully and follow all 

instructions when mixing and applying either herbicide. 

Aquatically approved formulations of glyphosate (e.g., 

Rodeo® and Aquamaster®) and imazapyr (e.g., Habitat®) 

must be used in or near water. When using these 

formulations, a surfactant approved for aquatic use must also 

be added to the spray mix. 

Herbicide Application 

Precautions should be taken to protect non-target plants 

(particularly woody species) from both direct spray and 

spray drift of glyphosate and especially imazapyr. Also, 

imazapyr may kill or injure non-target plants through 

runoff, movement in soil, or root exudation from treated 

plants. Therefore, imazapyr should not be used in 

residential, urban, or wildland-urban interface (WUI) areas 

where ornamental vegetation or turf grass may be affected. 

For foliar applications with glyphosate, buffelgrass plants 

should be at least 50% green before spraying. Better 

control will be obtained when plants are actively growing 

and are more than 80% green. This generally occurs within 

2 to 6 weeks following heavy summer rains. However, 

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Table 2. Herbicide recommendations 

Common 

Chemical 

Name 

(active 

ingredient) 

Product 

Example(s)1 

Broadcast 

Treatment 

(rate per acre) 

Spot 

Treatment 

(spray 

solution)2 

Time of 

Application Remarks 

Glyphosate Roundup Pro 

Roundup Ultra 

Rodeo 

Aquamaster 

Accord 

Kleenup Pro 

[many others 

available] 

Use 3 quarts per acre 

for formulations with 

3 lbs. ai per gallon 

(e.g., Roundup Pro) or 

2.25 quarts per acre 

for formulations with 

4 lbs. ai per gallon 

(e.g., Rodeo). 

2 to 5% Spray when 

buffelgrass is 

actively growing 

as indicated by 

bright green and 

glossy leaves. At 

least 50% of plant 

should be green. 

A rate of 2.25 lbs. ai per acre is 

recommended when broadcast 

spraying. Read label carefully 

to mix the proper rate of 

application. 

Immobile in soil. This herbicide 

is a non-selective amino acid 

inhibitor and will kill desirable 

A 1% w/w addition of 

ammonium sulfate or 

other acidifier may be 

necessary to adjust 

water to a neutral pH. 

vegetation. It is more active on 

grasses than herbaceous forbs 

or broadleaf plants and is least 

active on woody species. 

Imazapyr Arsenal 

Habitat 

Chopper 

Stalker 

Assault 

[many others 

available] 

Use 2 quarts per acre 

(with formulations of 

2 lbs. ai per gallon) 

Methylated seed oil 

may increase 

effectiveness of 

imazapyr applications. 

To protect nontarget plants during 

IPT, a reduced 

spray solution of 

0.5 to 1.5% is 

recommended. 

Otherwise, higher 

solution rates listed 

on product labels 

may be used if 

Foliar or crowndirected 

applications may 

be made at any 

time while 

buffelgrass is 

growing. 

Apply in a spray solution of at 

least 15 gallons per acre when 

broadcast spraying. Herbicidal 

activity may be slow. 

This herbicide is a nonselective amino acid inhibitor 

and will kill desirable 

vegetation, including forbs and 

impacts to nontarget plants are 

secondary 

considerations. 

woody species. In addition to 

spray drift, non-target plants 

may also be killed or injured by 

imazapyr through runoff, 

residue movement in soil, or 

root exudates from treated 

plants. Therefore, imazapyr 

should not be used in 

residential, urban, or wildlandurban interface (WUI) areas 

where ornamental vegetation or 

turf grass may be affected. 

1 Trade names for products are provided for example purposes only, and other products with the same active ingredient(s) may be available. Individual 

product labels should be examined for specific information and appropriate use with buffelgrass. 

2 Spray solution is the herbicide/water ratio in a spray mix that may be used for spot treatment with backpack or hand-held sprayers. The amount of product 

applied during an annual growing season must not exceed the maximum application rate per acre as specified by the product label – refer to the product 

label for the site type and application. 

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green-up of buffelgrass sufficient enough for glyphosate 

application may not occur during seasons when rainfall 

is insufficient. Re-treatment of buffelgrass previously 

treated with glyphosate is generally necessary to ensure 

that all plants are completely killed. 

Use of imazapyr potentially provides greater flexibility 

for buffelgrass control as compared to glyphosate since 

imazapyr may be applied when buffelgrass green-up is 

less than 50%. With a half-life of up to 142 days in soil, 

some imazapyr residues may remain in the soil beyond 

the normal green-up period. Imazapyr may be applied 

foliarly during green-up as an individual plant treatment 

(IPT) at a 0.5 to 1.5% v/v rate. Higher rates listed on 

product labels may be used if impacts to non-target 

plants are secondary considerations. To protect 

desirable trees or shrubs, do not apply imazapyr within 

twice the drip line (canopy edge) distance. For desirable 

cacti, imazapyr should not be applied closer than at 

least twice the extent of their lateral root system. 

Applications of imazapyr on land should include 

methylated seed oil (MSO) at a rate of 1% v/v rate (i.e., 

1.28 fl. oz. per gallon of water). 

To limit impacts to non-target plants during herbicide 

application, a backpack or hand-held sprayer may be 

used to spray small buffelgrass infestations. Backpack 

or hand-held sprayers should be calibrated so that a 

known amount of spray material will be applied per 

plant or given area. With both glyphosate and imazapyr, 

enough spray should be used to moisten the leaves, but 

not so much that spray drips off the plant. Adding a 

blue or red dye to the solution will aid in identifying 

treated plants. A team of applicators walking together in 

a line about 10 feet apart is most effective for spraying 

a defined area systematically. This method is 

particularly effective for treating smaller, less dense 

infestations. For large infestations on accessible lands, 

it is generally more practical to use calibrated ATV or 

UTV sprayers or boom sprayers that are tractor-pulled 

or mounted on a truck. Aerial applications of 

glyphosate are currently being used in Arizona to 

control buffelgrass over large landscape areas, 

especially those with rough terrain. 

If using backpack sprayers for IPT with imazapyr, 

special attention should be given to controlling the 

amount of imazapyr applied to each plant since 

excessive amounts of the herbicide increase the risk of 

off-target movement. A standard period of time should 

be set for spraying individual buffelgrass plants such 

that the foliage is sufficiently wet but runoff is avoided. 

To minimize small driftable spray droplets, drift 

reduction nozzles such as air induction nozzles should 

be used as well as a flow control valve that regulates 

pressure at the nozzle head. Spray drift may also be 

reduced by delivering a crown-directed spray of 

relatively large droplets within the inner 70% portion of 

a buffelgrass plant. Exterior spraying of buffelgrass 

foliage is more effective than crown-directed 

applications; however, exterior spraying may result in 

greater spray drift or the spraying of non-target plants. 

Management Strategies 

In areas of the Southwest where buffelgrass is not 

already established, early detection and rapid response 

(EDRR) should be used to eradicate new infestations at 

the earliest stages. When eradication is no longer 

feasible, a combination of physical and cultural control 

methods, chemical treatments, and possibly grazing 

should be used as part of an integrated management 

strategy to control or slow the colonization process. 

Buffelgrass seed production should be disrupted as 

much as possible, and the biomass, density, and 

viability of live buffelgrass plants should be decreased. 

In most cases, at least 2 or more consecutive years of 

field treatments will be necessary to eliminate or 

substantially reduce buffelgrass infestations and 

seedbanks. Since it is ordinarily useless to treat an area 

only one time without retreatment, sufficient resources 

must be allocated for the area where control is 

attempted. Only an area that can be retreated 

successfully should receive initial treatment so that 

resources are available to respray or retreat as 

necessary. Previously treated areas should always be 

continuously monitored and retreated when necessary to 

control recovering buffelgrass patches. Failure to 

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perform follow-up management may result in a return 

of the infestation to pretreatment levels. 

Adaptive Management 

Current experience and research suggest that there will 

not be one overarching process or set of tactics for 

controlling buffelgrass consistently. Therefore, realistic 

goals and objectives should be established to manage 

buffelgrass infestations occurring broadly across a 

given landscape. To improve long-term success, 

consider using an adaptive management approach with 

overall goals of reducing fires and maintaining or 

restoring desirable plant communities. The stepwise 

process for adaptive management involves: 

1. Assessment of the overall weed problem, 

2. Establishing management goals and objectives, 

3. Implementation of control strategies and 

measures, 

4. Monitoring the effectiveness of management 

actions, 

5. Evaluating actual outcomes in relation to expected 

results, and 

6. Adjusting practices as necessary. 

Steps of this process should be repeated in sequence as 

part of a continuous learning cycle that improves 

management planning and strategy by learning from the 

outcomes of previous management actions. In general, 

an adaptive management approach is considered to be 

successful if: 

1. Stakeholders are actively involved and remain 

committed to the process, 

2. Monitoring and assessment are used to adjust and 

improve management decisions, and 

3. Management goals and/or objectives for the 

resource are being achieved. 

References and Further 

Information 

Arizona-Sonora Desert Museum. 2012. Fountaingrass 

(Pennisetum setaceum). Available athttp://www. 

desertmuseum.org/invaders/invaders_ 

fountaingrass.php (accessed Dec. 2012). 

Baldwin, K. 2009. Buffelgrass Control Research Project 

Background Information. Available at 

http://www.buffelgrass.org/pdf/buffelgrassresearch-background-information.pdf (accessed 

Feb. 2010) 

Bales, L.S., E.D. Grahmann, F.S. Smith, T.E. Fulbright, 

and M.W. Hehman. 2009. Evaluation of 

Herbicides for Control of Buffelgrass and Kleberg 

Bluestem. Available at http://ckwri.tamuk.edu/ 

fileadmin/user_upload/docs/STN/Posters/ 

Evaluation_of_Herbicides_for_Control_of_Buffel 

grass_and_Kleberg_bluestem.pdf (accessed Feb. 

2010) 

Devoe, N., B. Nowak, and S. Florence. 2009. Effective 

Management of Invasive Plants. Rangelands 

31(3):21-24. Available at 

http://www.srmjournals.org/doi/full/10.2111/ 

1551-501X-31.3.21 (accessed Feb. 2010) 

Friedel, M., D. Butler, S. van Leeuwen, J. Virtue, and 

D. Agnew. 2008 Weed Management Guide: 

Buffelgrass. Available at http://www.weedscrc. 

org.au/documents/wmg_buffel%20grass.pdf 

(accessed Feb. 2010) 

Gardener, C.J., J.G. McIvor, and A. Jansen. 1993. 

Passage of legume and grass seeds through the 

digestive tract of cattle and their survival in 

faeces. J. Applied Ecology. 30(1):63-74. 

Grice, T. and T. Martin. 2006. Weed Management: 

Managing for Biodiversity in the Rangelands. 

Australia Department of the Environment and 

Heritage. ISBN 0 6425 51243. pp. 30-37. 

Available at http://www.environment.gov.au/ 

land/publications/pubs/weed-management17-

20.pdf (accessed Feb. 2010) 

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Halvorson, W.L. and P. Guertin. 2003. USGS Weeds in 

the West project: status of introduced plants in 

southern Arizona parks. Tucson (AZ): USGS, 

Sonoran Desert Res. Station, Univ. of Arizona. 

Hershdorfer, M. and R. Garner. 2007. Santa Rita 

Experimental Range: Buffelgrass Control in PMC 

Exclosure. Tucson Plant Materials Center. Tucson, 

AZ. Available at http://www.plant-materials.nrcs. 

usda.gov/pubs/azpmcpr8027.pdf 

Jernigan, M.B. 2013. Use of Uprooted Invasive 

Buffelgrass (Pennisetum ciliare) Parent Plants at 

Thatch to Reduce Progeny Seedling Emergence. 

M.S. thesis. School of Natural Resources and the 

Environment. Univ. Arizona. Tucson,AZ. 

Morisawa, T. 2000. Weed Alert: Cenchrus ciliaris L. The 

Nature Conservancy. Available at 

http://www.invasive.org/gist/moredocs/cencil01.pdf 

(accessed Feb. 2010) 

Northam, E., W. Meyer, J. Arnold-Musa, E. Carrillo, K. 

Egen, and M. Hershdorfer. 2009. Non-Native 

Invasive Plants of Arizona. Conservation Districts 

and RC & D Areas of Arizona and the University of 

Arizona CooperativeExtension. pp. 8-9. Available 

at http://cals.arizona.edu/pubs/natresources/ 

az1482.pdf (accessed Feb. 2010) 

Tu, M., C. Hurd, and J.M. Randall. 2001. Weed Control 

Methods Handbook: Tools and Techniques for Use 

in natural areas. The Nature Conservancy. Wildland 

Invasive Species TEAM, version April. Available 

at http://tncweeds.ucdavis.edu (accessed June 2016) 

Tu, M. 2002. Cenchrus ciliaris L. The Nature 

Conservancy: Wildlands Invasive Species Team. 

Dept. of Vegetable Crops and Weed Sciences Univ. 

Calif. Davis. Available athttp://www. 

imapinvasives.org/GIST/ESA/esapages/documnts/ 

cenccil.pdf (accessed Feb. 2010) 

USDA Natural Resources Conservation Service. 2010. 

The PLANTS Database. National Plant DataCenter. 

Baton Rouge, LA. Available at 

http://plants.usda.gov (accessed Nov. 2010) 

VanDevender, T.R. and M.A. Demmitt. 2006. Conservation 

of Arizona Upland Sonoran Desert Habitat. Status and 

Threats of Buffelgrass (Pennisetum ciliare) in Arizona 

and Sonora Project # 2004-0013-003. Arizona-Sonora 

Desert Museum. Available at http://www. 

Desertmuseum.org/programs/buffel_survey_report.pdf 

(accessed Feb. 2010) 

Williams, B.K., R.C. Szaro, and C.D. Shapiro. 2009. 

Adaptive Management: The U.S. Department of the 

Interior Technical Guide. Adaptive Management 

Working Group, U.S. Department of the Interior, 

Washington, DC. https://www2.usgs.gov/sdc/doc/ 

DOI-%20Adaptive%20ManagementTechGuide. pdf. 

Woods, S.R., J.S. Fehmi, and D.M.Backer. 2012. An 

assessment of revegetation treatments following 

removal of invasive Pennisetum ciliare (buffelgrass). 

Journal of Arid Environments. 87:168-175. 

WSSA Herbicide Handbook Committee. 2014. Herbicide 

Handbook of the Weed Science Society of 

America. 10th ed. WSSA, Lawrence, KS. 

Suggested Websites 

Arizona-Sonora Desert Museum: 

https://www.desertmuseum.org/buffelgrass/ 

For information about calibrating spray equipment: 

NMSU Coop. Ext. Serv. Guide #A-613 Sprayer 

Calibration. Available at: http://aces.nmsu.edu/ 

pubs/_a/A-613.pdf 

Syracuse Environmental Research Associates, Inc. 2011a. 

Glyphosate Human Health and Ecological Risk 

Assessment – Final Report. SERA TR-052-22-

03b. Report dated March 25, 2011. Available at 

http://www.fs.fed.us/foresthealth/pesticide/ 

risk.shtml 

Syracuse Environmental Research Associates, Inc. 2011b. 

Imazapyr – Human Health and Ecological Risk 

Assessment – Final Report. SERA TR-052-29-03a. 

Report dated December 16, 2011. Available at 

http://www.fs.fed.us/foresthealth/pesticide/ 

risk.shtml 

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For more information or 

other field guides, contact: 

USDA Forest Service 

Southwestern Region 

Forest Health 

333 Broadway Blvd., SE 

Albuquerque, NM 87102 

Or visit the Southwestern Region’s 

website for invasive species: 

http://www.fs.usda.gov/goto/r3/invasivespecies 

The use of trade or firm names in this publication is for reader 

information only and does not imply endorsement of any 

product or service by the U.S. Department of Agriculture. 

Recommendations made here for 

pesticide use are not obligatory, 

nor do they imply that discussed 

uses have been registered. All 

uses of pesticides must be 

registered by appropriate State 

and/or Federal agencies before 

they can be applied 

CAUTION: Pesticides can be 

injurious to humans, domestic 

animals, desirable plants, and fish or other wildlife—if they 

are not handled or applied properly. Use all pesticides 

carefully and lawfully. Follow recommended practices for the 

disposal of surplus pesticides and pesticide containers.