United States Department ofAgriculture

Field Guide for Managing

Siberian Elm in the Southwest

Forest 

Service

Southwestern

Region TP-R3-16-17 Revised June 2017
Cover Photos

Top left: John M. Randall, The Nature Conservancy, Bugwood.org 

Lower left: John M. Randall, The Nature Conservancy, Bugwood.org 

Lower right: Richard Old, XID Services, Inc.,Bugwood.org

Lower center: Steve Hurst, USDA-NRCS Plants Database, Bugwood.org

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1 

Siberian elm (Ulmus pumila L.)

Elm family (Ulmaceae)

Siberian elm is common in southwestern States and islisted

as a noxious tree in New Mexico. This field guide serves as 

the U.S. Forest Service’s recommendations for

management of Siberian elm in forests, woodlands, and

rangelands 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 located in northeastern 

New Mexico, western Oklahoma, and the Texas panhandle.

Description

In moist environments, Siberian elm (synonyms: Asiatic 

elm, dwarf elm, and Manchurian elm) is a fast-growing, 

hardy, mid-sized (60 to 70 feet tall), deciduous tree. In drier 

locations, it is smaller and takes on a shrubby appearance.

Siberian elm has an open crown with upward-growing

branches and many flexible, pendulous, brittle branchlets 

that easily break off. There is usually a large accumulation 

of leaves and woody litter that build up in the understory

beneath Siberian elm. Siberian elm is often confused with 

Chinese elm, Ulmus parvifolia, which grows only to 30 to 

40 feet in height and typically has leaves longer than 2 

inches. 

Growth Characteristics

• Deciduous tree (up to 70 feet tall) with an open, 

rounded crown that is 3/4 as wide as it is tall;slender, 

spreading branches.

• Trunk has rough grey or brown bark with shallow, 

irregular furrows.

• Twigs are silver-grey, yellowish, or grayish-brown, 

zigzag-shaped with a leaf bud at each bend and

scattered spots (lenticels).

• Alternate leaves; 0.5 to 2.5 inches long, tapered at 

each end with a simple serrate or entire margin; 

upper surface deep green; lower surface paler green 

with hairs along vein axils. Leaves may turn yellow

in autumn.

• Clusters of 2 to 5 small, green, drooping flowers 

without petals occur from February through April 

before leaves develop.

• Reproduces primarily via seed; roots re-sprout when 

top growth is damaged. 

• Clusters of smooth, circular, winged, samara-type 

fruit with single seed in the center occur from Aprilto

May.

Ecology

Impacts/Threats

With adequate soil moisture, Siberian elm germinates 

readily and grows rapidly. It quickly out-competes 

desirable native plants, especially in sparsely vegetated or 

disturbed areas. Ahigh density of Siberian elm can reduce 

shade-intolerantspecies (including quality forage) and 

decrease overall species diversity.

Site/Distribution

Siberian elm prefers open areas but tolerates a wide range

of conditions, which includes long periods of drought, cold

winters, poor soil conditions, high winds, and low 

moisture. In the Southwest, it commonly grows on 

disturbed grounds, moist streambanks, pastures and 

rangelands, and rights-of-way along roads and railroads. 

Siberian elm does not tolerate flooding and seldom invades 

mature forest because of its high requirement for sunlight.

Spread

Siberian elm seed is primarily dispersed via wind, although

seed may also be transported by water and animals. Seed

may be carried long distances by adhering to surfaces and

undercarriages of logging equipment and vehicles. The tree

is still sold commercially and is used for shade,

shelterbelts, and windbreaks in Oklahoma andTexas.

Invasive Features

Siberian elm can dominate new locations in just a few

years due to its adaptability, high rate of seed production 

and germination, and rapid growth.
2

Management

It is very difficult to restore native plant communities with 

large infestations of Siberian elm. However, populations

can be reduced with careful planning and long-term

actions. Consider the following actions when planning a 

management approach:

• Maintain healthy and diverse plant communities to 

prevent or limit Siberian elm infestations.

• Limit disturbance and/or promptly revegetate 

disturbed areas with desirable perennial forage

species, especially perennial grasses.

• Detect and eradicate new populations of Siberian 

elm as early as possible.

• Combine mechanical and chemical methods for 

most effective Siberian elm control.

• Implement monitoring and a follow-up treatment 

plan for missed plants and seedlings.

• Map and keep annual records of reported 

infestations.

Table 1 summarizes some management options for 

controlling Siberian elm under various situations. Further 

details on these management options are explained below.

Choice of which method(s) to use will depend on a 

number of factors including where the population is 

located and the stage of tree life. Consider carefully the 

current land use and site conditions (accessibility, terrain, 

microclimate, other flora and fauna present, etc.). Other 

important considerations include treatment effectiveness, 

cost, and the number of years needed to achieve control. 

More than one control method may be needed for a 

particular site.

Physical Control

To control Siberian elm, it is necessary to destroy the root 

system. Physical control can be done on a range of

scales—from individual plant removal (from hand tools to

excavators) to broad-scale clearing (from tillers to

bulldozers). Mechanical clearing often requires repeated

applications.

Manual Methods

Hand removal – Newly emerged seedlings and saplings

with a stem diameter less than 3/8 inch are easily removed 

by hand pulling or hoeing. Small trees with a stem

diameter between 3/8 and 2.5 inches may be hand 

grubbed with a shovel, hoe, or weed tool such as the 

Weed WrenchTM or RootTalonTM.

Suppression by cutting – In areas with just a few large 

trees, trunks may be cut close to the ground to remove top 

growth. Anticipate that root and trunk re-sproutswill 

return later in the growing season and will require

repeated follow-up cutting. Cutting is more effective 

when followed up with a chemical treatment (see cutstump treatment in the “Chemical Control” segment

below).

Girdling – In late spring to midsummer on larger trees, 

use an ax, saw, or chain saw to make two horizontal,

circumferential cuts around the entire trunk. Place one cut

3 to 4 inches above the other through the bark and 

cambial tissue. Using a blunt object, such as the ax head, 

knock off and remove the bark between the cuts. Care 

should be taken to remove only the bark and outside 

cambial tissue while minimizing damage to the wood 

(xylem). Deeper cuts made into the wood often trigger

Siberian elm into re-sprouting from the roots. Leave 

girdled trees in place for 2 to 3 years and check 

periodically to ensure that cut edges in the bark do not 

grow together again. See the “Chemical Control” segment

below for information about combining girdling with a 

herbicide application.

Mechanical Methods

Tractor-mounted grubbing implements are especially

useful for control of scattered individual trees. Agrubbing 

tool mounted as part of a tractor’s front hydraulics can

drive a blade into the soil to sever below the root crown 

and uproot the plant onto the surface. Grubbed Siberian 

elm should be piled, dried, and burned or mulched rather 

than left on the surface to prevent the plant from rerooting. After treatment, it is necessary to monitor

grubbed areas for 2 or 3 years and re-treat as necessary.
3

Table 1. Management options*

Site Physical Control Cultural Control Biological 

Control Chemical Control

Roadsides,

irrigation ditches,

fence lines, or 

non-crop areas

Seedlings (< 3/8" diam.) and 

saplings (3/8 to 2.5" diam.): dig 

or grub with shovel, hoe or weed

tool.

Small trees (2–3" diam.): remove 

individual plants using the 

cut/stump method.

Larger trees (> 3" diam.): girdle 

trunks and leave in place or use 

cut-stump method. Where access 

is not limiting, remove trees with 

an excavator or backhoe. Control 

re-sprouts as needed.

Use seed, mulch, and fill 

materials certified to be 

weed-free.

Train road crews to identify

and report infestations along 

roads; implement

requirements for vehicle

operations.

Use weed screens on 

irrigation canals.

Consider 

intensive, shortterm grazing of 

seedlings and 

young trees with 

male goats. 

Light infestations: for trunks < 

3' diam. and less than 8' tall, use 

basal bark treatment; for trunks 

> 3" diam., girdle or use cutstump with herbicide.

Dense infestations: use foliar 

application with backpack 

sprayer; truck/ATV-mounted

sprayer. Wash under vehicle 

after application to prevent

spread.

Rangelands,

pastures, or

riparian corridors

Light infestations: use an 

individual plant method to 

remove trees.

Dense infestations: remove stems 

with heavy machinery in the 

winter; follow-up with chemical 

treatment to control re-sprouts in 

late summer.

Reseed with certified, weedfree seed; fertilize and 

irrigate, if possible, to make 

desirable plants more

competitive.

Same as above. For light infestations with 

Siberian elm interspersed with 

desirable native plants, use a 

backpack sprayer to treat

individual plants (basal bark, 

cut-stump, or girdling with

herbicide).

For dense infestations in 

disturbed areas with few 

desirable plant species present,

use broadcast spraying.

Wilderness, other

natural areas,

and/or small

infestations

Same as above. Use seed certified to be 

weed-free.

After passing through

infested areas, inspect and

remove seed from animals,

clothing, and vehicles before 

entering treated or uninfested areas.

Same as above. Same as above.

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

Large-scale clearing – In areas densely infested with 

Siberian elm, consider removing trunks and stems during 

winter with heavy machinery such as an excavator or

backhoe. Excavators can be used to remove individual

trees selectively, and skilled operators of this equipment

can efficiently remove the top growth and most root

material. Pulled material should be immediately destroyed

by shredding or piled for later burning, shredding, or

mulching. Later in the summer, sprouting from 

incompletely extracted root parts is often common when 

left in the soil. Therefore, follow-up control with 

mechanical or chemical treatment will be necessary.

Prescribed Fire

Use of fire is usually not recommended for Siberian elm 

control. However, a prescribed burn may be used in

certain fire-adapted areas to remove and suppress top

growth. Depending on fire intensity, burning will control

seedlings, but saplings and older trees will usually survive 

and regrow from the root system.

Cultural Control

Siberian elm is available for sale in nurseries and has 

been planted widely as a fast growing hedge or windbreak

tree in conservation plantings. While the popularity of
4

using Siberian elm as a drought-resistant planting option

is not as common as it was in the past, public education is 

still needed to raise awareness of the invasive

shortcomings of the species.

Land managers, the local public, and road crews should be

educated as to how to identify nonnative noxious species

such as Siberian elm so they can help report allsuspected

infestations. Seed and materials used for mulch, forage, or 

fill should be certified to be weed-free. Vehicles, humans, 

and livestock should be discouraged from traveling 

through infested areas; and a program to check and 

remove seeds from vehicles and livestock should be 

implemented to help stop dispersal. If possible, weed 

screens should be used on irrigation water intakes in 

infested areas to prevent seed transportation in irrigation

canals.

Biological Control

Grazing

While published research does not specifically address 

livestock grazing on Siberian elm, anecdotal information

suggests mature male goats will selectively graze

seedlings and young trees. An intensive, short-term,

prescribed grazing approach with goats could be one 

component in a successful Siberian elm management 

program in selected areas.

Classical Biological Control

There are no classical biocontrol agents (insects, 

pathogens, etc.) currently approved by USDA for use with 

Siberian elm.

Chemical Control

Herbicide control—used either alone or in combination

with another method—has been used with varying success 

on Siberian elm. The choice of which herbicide to use and

how to apply it is influenced by many factors including 

the time of year to be sprayed, the plants particular growth 

form (i.e., a low growing, multi-stemmed shrub versus a 

mid-sized, single stem tree), site accessibly, and other

considerations. The density of the Siberian elm population

and proximity to other desirable plants further complicates

how best to proceed with herbicide control.

Herbicide products recommended in table 2 will have 

different requirements and restrictions according to the 

label. Aquatically approved herbicide formulations and 

surfactants must be used in or near water. It is important 

to read and carefully follow all instructions and warnings

provided on the herbicide label. Consult the registrant if 

you have questions or need further detail.

Herbicide Application

There are several registered products that can be applied in 

a variety of ways including (1) foliage application, (2) soil 

application, (3) topical application to cut-stems and 

stumps, and (4) basal spraying. Herbicide spraying is 

rarely successful as a one-time treatment so it should be 

anticipated that treated areas will need to be monitored for 

several years and re-sprouts and new seedlings will 

require further treatment. Care should always be taken 

when spraying any herbicide near desirable plants. 

Foliar spraying may be used to control seedlings,

saplings, and mature trees of Siberian elm that are 

generally less than 6 feet in height and are easily covered 

with a spray application. Apply herbicide to fully 

expanded leaves using individual plant treatment (IPT 

spot spray) with a backpack sprayer, or treat clusters of 

trees using a tractor or truck-mounted sprayer (broadcast 

application). Any equipment used to spray herbicide 

should be calibrated.

When using the IPT approach, take care to direct spraying 

so that desirable, nearby non-target plants are not harmed. 

Thoroughly wet all green leaves and shoots, especially 

near the top of the shrub or tree. Plants should be wetted 

without allowing dripping to occur. Use a 1.5 percent v/v 

solution mix using triclopyr (Garlon® 4) to spray IPT. 

Glyphosate, imazapyr, or a spray mixture of 

aminocyclopyrachlor combined with imazapyr and 

metsulfuron methyl (Viewpoint®) are also effective 

herbicide treatments as described in table 2. When mixing 

any herbicide solution, consult the label on the need to 

add a nonionic surfactant (a 0.25 percent by volume is 

usually added). Also, adding a blue indicator dye (0.5 

percent) to the mixture is recommended to help view 

coverage of sprayed plants. The practicality of using a 

foliar spray approach depends primarily on tree density
5 

Table 2. Herbicide recommendations

Common

Chemical Name

(active 

ingredient)

Product

Example1

Broadcast 

Treatment 

(rate per 

acre)

Spot 

Treatment 

(spray 

solution)2

Time of

Application Remarks

Triclopyr Garlon 4

[many others

available] 

3–6 quarts Low volume:

1.5%

High volume: 1–

1.5%

Summer/early

fall when tree is

actively growing

and fully leafed

but before fall

color begins. 

Selective, systemic broadleaf herbicide;

will not impact grasses. Low soil activity;

no impact to groundwater.

Follow label for quantity of water and

nonionic surfactant to mix.

Garlon 4 volatilizes above 86 °F.

Glyphosate Rodeo,

Roundup Pro 

[many others

available] 

Rodeo: 3–7.5 

pints

Roundup : 

1.5–3.3 

quarts

Rodeo: 

0.75–1.5%

Roundup: 

1–1.5%

Same as above. Nonselective herbicide; can injure

surrounding plants and open more area for

weeds. 

Follow label for how much water to mix.

Imazapyr Arsenal

Habitat 

Chopper 

Stalker

[others

available] 

Arsenal: 

1–1.5 

pints

Chopper: 2–3 

pints

Arsenal: 1-5%

Chopper: 5%

Same as above. Nonselective herbicide; overspray can 

injure surrounding plants and open up

additional area for weeds.

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.

Aminocyclopyrachlor

+ imazapyr + 

metsulfuron methyl

Viewpoint 13–20 ounces Consult label for 

spot applications.

Same as above. Apply as high volume or broadcast foliar

spray.

Nonselective herbicide used on non-crop 

sites; may cause temporary injury to some 

grass species.

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 Siberian elm.

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.

and access to the area to be sprayed. An efficient way for 

treating younger plants and re-sprouts across a large area

is to use a team approach where each member equipped 

with a backpack sprayer walks side-by-side about10 feet 

apart and spot sprays plants in their zone. A blue or red 

indicator dye in the spray mixture is very helpful for 

determining coverage. Sprayed areas should be revisited 

after 2 or 3 years to re-treat surviving or missed plants.

Basal bark spraying is a highly selective, yet labor

intensive method that is most appropriate for controlling

smaller trees less than 8 feet tall with stems that are about 

2 to 3 inches in diameter. Use a backpack sprayer

equipped with an adjustable nozzle (X0 to X1) to deliver 

a mist spray from the base of the stem up to 12 inches 

above the ground. Spray a band of herbicide around the 

entire circumference of the stem until the bark is wet but not

running off. A20 percent solution of triclopyr combined

with 80 percent penetrating oil should be mixed and applied 

in the winter (January or February) or from mid-summer to 

early fall (June-September). Add blue dye to the chemical 

solution as an aid for determining coverage. Leave treated 

trees standing in place so they can be revisited the next year 

and, if necessary, new foliage can be spotsprayed.

Cut-stump treatment with herbicide allows specific trees 

to be immediately removed. Use a chain saw to cut the 

trunk as close to the ground as possible. Within 5 to 15
6

minutes of cutting, apply glyphosate to the cut surface 

using a paint brush, wick applicator, or low-volume 

hand-held sprayer. Although the product label indicates a

50–100 percent concentration of glyphosate should be 

used, literature indicates that a 20 percent glyphosate 

solution is effective in preventing root re-sprouts.

Girdling with herbicide, as described in part in the

“Physical Methods” section above, is an effective control

treatment for larger trees. Spray or paint the cut-surface

of girdled areas with a 50–100 percent concentration of 

glyphosate or triclopyr. The most effective time to girdle

and apply chemical treatment is during summer when

Siberian elm is fully leafed-out and actively growing.

Management Strategies

The first priority in Siberian elm management is early 

detection and control to prevent widespread

establishment. Small infestations on otherwise healthy 

sites should be given high priority for treatment. Siberian 

elm growing in riparian corridors along waterways 

should be treated by starting at the upper reaches of the 

drainage and then progressing downstream.

Numerous strategies have been used for Siberian elm

control, and local situations usually dictate the best

approach to follow. A popular approach is to use a basal

spray or a cut-surface treatment initially and then follow 

up later by using a foliar active herbicide to spot spray

new seedlings, sprouts, and root suckers. Once Siberian 

elmis controlled, planting desirable trees and other

restoration activities may be used to help prevent the 

problem from recurring. This includes establishing a 

thick cover of competing vegetation (i.e., desirable trees, 

shrubs, and grasses) that can provide shade and crowd 

out Siberian elm.

Strategies to contain and reduceSiberian elm populations 

require long-term planning and integrated management. 

A combination of control methods applied over 5 to 10 

years is usually necessary to provide effective control of 

Siberian elm. 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. After 

initial treatment, it is especially important that resources are 

also available to respray or retreat the treated area as 

necessary. Regardless of the initial strategy used, the key to

successful long-term control of Siberian elm is to monitor 

treated areas for several years after initial treatment. Always 

be prepared to remove any new plants quickly. Failure to

perform follow-up monitoring and treatment could result in 

a return to pretreatment density levels.

Adaptive Management

It is important to establish realistic goals and objectives 

when managing Siberian elm, especially when infestations

occur extensively across a given landscape. To improve 

long-term success, consider using an adaptive management 

approach with the overall goal of 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 may be 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.
7

References and Further

Information

Bargeron, C.T., C.R. Minteer, C.W. Evans, D.J.

Moorehead, G.K. Douce, and R.C. Reardon. 

(coords.) 2008. Invasive Plants of the United States 

CD-ROM: Identification, Biology and Control. 

USDA Forest Serv. FHTET-2008-11. Available at

http://www.invasive.org/weedcd/ (accessed May

2010)

Colorado State University Extension, Denver Botanic 

Gardens, and Green Industries of Colorado, Inc. 

Plant Talk Colorado. 2016. Elm trees, 1746. 

Available at http://www.ext.colostate.edu/ 

ptlk/1746.html (accessed October 2016)

Cowling Arboretum at Carleton College. 2008. Siberian 

Elm (Ulmus pumila). Available athttp://apps. 

carleton.edu/campus/arb/species/invasives/siberian

_elm (accessed May 2010)

Herman, D.E et al. 1996. North Dakota Tree Handbook. 

USDA, NRCS, ND State Soil Conservation 

Committee: NDSU Extension and Western Area 

Power Administration. Pp. III-117-118. Available at

http://www.ag.ndsu.edu/trees/handbook.htm 

(accessed May 2010)

Invasive Plant Atlas of the United States. Available at

http://www.invasive.org/weedus/index.html

(accessed May 2010)

Kennay, J. and G. Fell. 1990. Illinois Vegetation

Management Guideline: Siberian Elm (Ulmus

pumila). Ill. Nature Preserves Comm. Springfield,

Ill. Available at http://www.inhs.illinois.edu/

research/VMG/sibelm.html (accessed May 2010)

Lamming, L. 2001. Successfully Controlling Noxious 

Weeds with Goats: The Natural Choice That

Manages Weeds and Builds Soil Health. Alternative

Weed Strategies 21(4):19-23. Available at

http://www.beyondpesticides.org/weeds/publication

s/Goat_weed_ management.pdf (accessed June

2010)

North Dakota Department of Agriculture. 2003. Invasive 

Species Web-based Manual. Available at

http://www.agdepartment.com/noxiousweeds/pdf/ 

Siberianelm.pdf (accessed June 2010)

Parker, D.L, M.J. Renz, A. Fletcher, F. Miller, and J. Gosz.

2005. Strategy for Long-term Management of

Exotic Trees in Riparian Areas for New Mexico’s

Five River Systems. Available at

http://nmdaweb.nmsu.edu/animal-and-plantprotection/tamarisk-salt-cedar/lt_mgmt_of_exotic

_trees_1.pdf (accessed May 2010)

Pergams, O.R.W. 2006. Treating a Single-stem Can Kill

the Whole Shrub: A Scientific Assessment of

Buckthorn Control Methods. Natural Areas Journal

26(3):300-309. Available at http://www.pergams. 

com/uploads/NAJ.pdf (accessed June 2010)

Samuel Roberts Noble Foundation Plant Image Gallery.

Available at http://www.noble.org/WebApps/ 

PlantImageGallery (accessed in May 2010)

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

Methods Handbook. The Nature Conservancy.

USDA Forest Service, Northeastern Area, Forest Health

Protection Invasive Plant website. Available at

http://na.fs.fed.us/fhp/invasive_plants/weeds/ 

siberian-elm.pdf (accessed May 2010)

USDA Plants Database. 2010. Available at

http://plants.usda.gov/index.html (accessed May

2010)

Wieseler, S. 2005. Weeds Gone Wild Factsheet: Siberian 

Elm. Plant Conservation Alliance Alien Plant 

Working Group. Available at http://www.invasive. 

org/weedcd/pdfs/wgw/siberianelm.pdf (accessed in 

May 2010)

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

Adaptive Management: The U.S. Department of the 

Interior Technical Guide. AdaptiveManagement 

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

Washington, DC. Available at http://www.doi.gov/

initiatives/AdaptiveManagement/TechGuide.pdf 

(accessed October 2011)
8

Wisconsin Department of Natural Resources. Invasive 

Factsheet: Siberian Elm. Available at http://dnr.

wi.gov/invasives/fact/elm.htm (accessed May

2010)

Zheng, H., Y. Wu, J. Ding, D. Binion, W. Fu, R. Reardon. 

2005. Invasive Plants Established in the United 

States that Are Found In Asia and Their

Associated Natural Enemies-Volume 2. USDA

Forest Service FHET 2005-15. P. 139. Available at

http://www.invasive.org/weeds/asianv2.pdf 

(accessed May 2010)

Suggested Web Sites

For information on invasive species:

National Invasive Species Information Center

http://www.invasivespeciesinfo.gov/ 

Invasive.Org

https://www.invasive.org/species.cfm

For information about calibrating spray equipment: 

NMSU Cooperative Extension Service Guide A613 Sprayer Calibration. Available at 

http://aces.nmsu.edu/pubs/_a/A-613.pdf

Herbicide labels online:

http://www.cdms.net/
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.