!:§DA 

-

a 

United States Department of Agriculture 

Field Guide for Managing

Dalmatian and Yellow Toadflaxes 

in the Southwest 

Forest Southwestern 

Service Region TP-R3-16-06 Revised July 2017 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Cover Photos 

Top left: Dalmatian toadflax; Utah State University Archive, Utah State University, Bugwood.org 

Top right: Dalmatian toadflax flower; Bob Nowierski, Montana State University, Bugwood.org 

Bottom left: Yellow toadflax, David Powell, U.S. Forest Service, Bugwood.org 

Bottom right: Yellow toadflax flower; Wendy Van Dyk Evans, Bugwood.org 

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Dalmatian toadflax (Linaria dalmatica (L.) Mill. ssp. dalmatica) 

Yellow toadflax (Linaria vulgarisMill.) 

Figwort family (Scrophulariaceae) 

Dalmatian toadflax and yellow toadflax are invasive plants 

that have been introduced into the southwestern U.S. Both 

species are listed in New Mexico as noxious weeds; 

however, Dalmatian toadflax is listed only in Arizona. 

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

recommendations for management of Dalmatian and 

yellow toadflaxes 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 

Dalmatian toadflax (synonyms: broad-leaved toadflax, wild 

snapdragon) and yellow toadflax (synonyms: butter-andeggs, common toadflax, toadflax, Jacob’s ladder, common 

linaria, wild snapdragon) were brought from the 

Mediterranean region to the western U.S. as ornamentals 

Table 1. Growth characteristics 

and have since escaped to become widely growing invasive 

plants. These short-lived perennials produce new plants 

from adventitious buds on a re-sprouting root system that 

is both extensive and deep. Flowers of both plants are 

snapdragon-like. While similar in appearance, Dalmatian 

toadflax grows taller and produces new plants mainly from 

seed whereas yellow toadflax spreads mostly from root 

buds. Table 1 lists growth characteristics of both toadflax 

species. 

Ecology 

Impacts/Threats 

These aggressive weeds are highly adaptable and can outcompete winter annuals or shallow-rooted perennials for 

soil moisture. A high density of toadflax reducesthe 

availability of quality forage and diversity of flora and 

fauna species. Dalmatian and yellow toadflaxes contain 

glucoside compounds that are poisonous, especially to 

cattle; however, these plants typically are not grazed by 

animals. 

Species Life Span Growth and 

Root Habit 

Vegetative 

Appearance Flower Appearance Reproductive Method and Seed Appearance 

Dalmatian 

toadflax 

Short-lived 

perennial 

(generally < 5 

years) 

Averages 3 feet 

tall; up to 25 stems 

per crown during 

first year of 

growth; taproot 

and creeping 

lateral roots. 

Waxy, blue-green oval to 

heart-shaped; leaves 

clasp upper stem; rough, 

woody stem at base that 

becomes smooth, waxy 

and herbaceous near the 

top. 

0.75 to 1.5 inches long 

yellow, two-lipped flowers 

with an orange bearded 

throat and a long spur; 

flowers in leaf axils. 

Fruit 2 celled and 

irregular shaped. 

Reproduces mainly by seed 

and partly by adventitious 

root buds. 

Black, sharply angled seeds 

that are slightly winged. 

Produces 500,000 seeds per 

plant. 

Yellow 

toadflax 

Same as above. 1.5 to 3 feet tall; 

has taproot and 

extensive system 

of vertical roots 

with creeping 

laterals. 

Grows in tight 

clumps. 

Pale green, soft linear 

lanceolate leaves that are 

sessile and do not clasp 

stem; Upright, 

unbranched stem that is 

woody at the base and 

smooth at the tip. 

1-inch long yellow flowers 

with 5 fused petals (2 

upper lobes and 3 lower), 

an orange bearded throat, 

and a yellow spur; flowers 

in leaf axils. 

Fruit 2 celled and globe 

shaped. 

Reproduces primarily by 

adventitious buds on lateral 

roots. 

Seeds are dark brown to 

black, long, flattened, and 

winged. 

Produces 30,000 seeds per 

plant. 

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Site/Distribution 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Disturbance favors toadflax establishment. Both species 

thrive in degraded areas such as roadsides, cleared lots 

and fields, gravel pits, heavily grazed rangeland, and 

riparian zones. These weeds often establish in naturally 

occurring openings within sagebrush, ponderosa pine, 

and other woodland or parkland plant communities at 

higher elevations. Dalmatian toadflax favors cool, 

semiarid climates and coarse, dry soils with a neutral 

pH. Yellow toadflax favors moist soils and can tolerate 

subarctic conditions. 

Currently, large infestations of toadflax occur in all 

western States. In New Mexico, Dalmatian toadflax is 

typically found at elevations between 5,000 and 6,000 

feet, whereas yellow toadflax occurs at higher elevations 

between 6,000 and 9,500 feet. Infestations of both 

species are expanding in Arizona and New Mexico. 

Spread 

Yellow toadflax produces shoots from underground 

stems as early as March from which new, independent 

plants can form later during the growing season. Seed 

viability in yellow toadflax is quite low; therefore, the 

spread and persistence of plants in the field are mainly 

due to vegetative reproduction. Unlike yellow toadflax, 

Dalmatian toadflax spreads vegetatively and by seed 

with shoots emerging from these two sources in early 

April through May. Seed viability for Dalmatian 

toadflax is high with germination rates near 75 percent. 

Invasive Features 

Yellow toadflax can grow new shoots on lateral roots up 

to 10 feet away from parent plants. A singleDalmatian 

toadflax plant produces about 500,000 seeds from July 

through October depending on location, aspect, and 

availability of water. Seeds remain viable in the soil for 

up to 10 years, and roots are easily spread by machinery. 

Management 

Once the root system is established, Dalmatian and 

yellow toadflaxes are extremely competitive for water 

and resources; thus, they are difficult to eradicate or 

control. Early detection and prevention of population 

expansion should be the first priorities for managing 

these plants. The following actions should be considered 

when planning a management approach: 

• Maintain healthy plant communities to reduce or 

limit toadflax infestations. This may involve 

improving grazing management practices to 

prevent overgrazing. 

• Check hay and straw for presence of toadflax 

seed. Only certified weed-free hay and pellets 

should be fed to horses used in backcountry areas. 

• Detect, report, and eradicate new populations of 

toadflax as early as possible. 

• Combine mechanical, cultural, biological, and 

chemical methods for most effective toadflax 

control. 

• Implement monitoring and a follow-up treatment 

plan for missed plants and seedlings. 

• Map large infestations. Keep annual records of 

reported infestations. 

Table 2 summarizes some management options for 

controlling Dalmatian or yellow toadflax under various 

situations. Further details on these management options 

are explained below. Choice of individual control 

method(s) for these toadflaxes depends on the extent 

and density of infestation, current land use, and site 

conditions (accessibility, terrain, microclimate, other 

flora and fauna present, etc.). Other important 

considerations include treatment effectiveness, overall 

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

More than one control method may be needed for a 

particular site. 

Physical Control 

Physical methods to control toadflax should focus on 

destroying the root system. Surface treatments (such as 

mowing) used to reduce flowering and seed production 

can suppress infestations but will not kill the plants. 

Manual Methods 

Hand pulling, digging, or hoeing can be effective for 

seedlings or small infestations of toadflax. These 

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Table 2. Management options* 

Site Physical Control Cultural Control Biological Control Chemical Control 

Roadsides and In level terrain, use Use seed, mulch, and fill Use beetles, moths, or Apply in fall during late 

non-crop repeated cultivation materials certified to be weed-free. weevils as classical flowering stages. Use 

areas with disk or sweep-type Educate road crews to identify biocontrol agents (see truck or ATV-mounted 

cultivators about 8 to and report infestations along table 3). Effectiveness spraying equipment. 

10 times the first year roads; implement requirements of biocontrol agents Wash under vehicle 

followed by 4 to 5 for vehicle operations. may be limited when after application to 

times the second year. disturbance from road prevent spread. 

Follow up with operations interrupts an 

chemical control. agent’s life cycle. 

Rangeland In level terrain, use 

repeated cultivation 

with disk or sweep-type 

cultivators about 8 to 

10 times the first year 

followed by 4 to 5 

times the second year. 

Follow up with 

chemical control. 

Use seed and forage hay certified 

to be weed-free; use pellets for 

horses in backcountry areas. 

Check animals, clothing, and 

vehicles for seeds. Corral sheep 

for 11 days before moving to 

un-infested areas. 

Reseed treated areas if necessary 

Use beetles, moths, or 

weevils as classical 

biocontrol agents (see 

table 3). 

Closely manage grazing 

to prevent overuse. 

For extensive and dense 

infestations, use ground or 

aerial broadcast spraying. 

For less dense 

infestations, consider 

individual plant treatment 

with crews using 

backpack sprayers. 

to make desirable plants more 

competitive. Fertilization and/or 

irrigation may help establishment 

of desirable plants. 

Wilderness and Repeated hand-pulling, Use seed and forage hay certified Same as above Use backpack or hand-held 

other natural digging, or hoeing for to be weed-free; use pellets for sprayers. Broadcast 

areas seedlings and regrowth. horses in backcountry areas. spraying by aerial or 

Anticipate need to repeat 

treatments and monitor for 

~10 years. 

Check animals, clothing, and 

vehicles for seeds. Corral sheep 

for 11 days before moving to 

ground methods may be 

used on thicker stands if 

allowed. 

un-infested areas. 

Post signs warning visitors to 

inspect and remove seed from 

clothing, animals, and vehicles. 

Reseed treated areas if necessary 

to make desirable plants more 

competitive. Fertilization and/or 

irrigation may help establishment 

of desirable plants. 

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

methods are easier if done in sandy or moist soils. to mature. Therefore, debris should be destroyed by 

Although removal of the root is very difficult, it is burning or else bagged and removed from the site. If 

necessary for maximum effectiveness. Treatments flowers or seed are not present, plants may be pulled 

should be repeated several times per growing season, and left onsite. 

and the site should be revisited for many years to assure Mechanical Methods 

that new plants have not grown from dormant seed. Mowing, chopping, or cutting plants can suppress Proper disposal of debris is important to reduce further toadflax; but these practices are generally not spread. If flowers or seed are present, they will continue 

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recommended since new shoots can re-sprout rapidly from 

adventitious root buds in response. Repeated cultivation 

with a disk or a sweep-type cultivator can be effective if 

done for 2 or more consecutive years. However, 

mechanical control with these two implements is typically 

limited to agronomic settings since the terrain must be 

suitable for their use. Starting in May or June, cultivation 

should be done through the growing season as often as 

required to eliminate green growth. Do not allow new 

growth to be visible for longer than 7 to 10 days before 

repeating cultivation. Generally, 8 to 10 cultivations are 

required during the first season and at least 4 to 5 times in 

the second year. Consider reseeding the next spring or fall 

with desirable perennial forage species of varying root 

depths and growth habits. It will probably be necessary to 

use a follow-up chemical treatment to control new toadflax 

seedlings and re-sprouting of roots. Plan to periodically 

monitor the treated site for as many as 10 years, and then 

spot treat or hand pull plants as they emerge. 

If machinery is used to manage toadflax, the equipment 

should be cleaned after use to prevent movement of seed or 

root fragments into un-infested areas. 

Prescribed Fire 

Wildfire or controlled burns can destroy toadflax canopies, 

but plants taller than 2 inches tend to have well-developed 

roots and usually are not killed by heat from fire. Typically, 

there is prolific sprouting from Dalmatian and yellow 

toadflaxes after fire; therefore, burning is not 

recommended. However, burning Dalmatian toadflax 

seedlings less than 2 inches high with a propane torch has 

been used with some success in Oregon and Washington. 

Cultural Control 

Early detection and plant removal are critical in preventing 

establishment of toadflax species. Seed and materials used 

for mulch, forage, or fill should be certified to be weedfree; pellets may be used for horses in backcountry areas. 

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

educated in identifying these species (especially in the 

seedling stage) so they can help report all suspected 

infestations. Farm, rangeland, and outdoor recreation 

equipment can transport seeds; care should be taken to 

clean the equipment thoroughly before moving from 

infested areas to un-infested areas. If possible, weed 

screens should be used on irrigation water intakes in 

infested areas to prevent seed transportation in ditches or 

canals. Reseeding of treated areas may help establish 

desirable plants if native plants are not already present. 

However, native grasses generally increase rapidly in the 

season following herbicide treatment. 

Biological Control 

Grazing 

Toadflaxes contain glucosides that are poisonous to 

livestock when consumed in high quantity, but animals 

typically avoid eating these species. Care should be taken 

not to overgraze infested areas since overgrazing allows 

toadflax plants to become more competitive and abundant 

than desirable grazed species. Short-term, intensive 

grazing by sheep during spring and late season can 

suppress Dalmatian toadflax and limit seed production, as 

shown by field trials in Montana. However, follow-up 

herbicide treatment was still needed to control the toadflax. 

Classical Biological Control 

Under certain conditions, insect biocontrol agents can be 

used to help control toadflax species, but these agents will 

not completely eradicate them. Biocontrol agents for 

toadflax should be used only if infestations are large 

enough to sustain populations of these species. Some 

biocontrol agents are less effective when their life cycle is 

disturbed, either by the presence of livestock or by 

management actions involving the thistle. Treatments such 

as cutting or spraying may not allow the biocontrol agent 

to complete its life cycle. As a result, the needs of the 

biocontrol agent (if present) should be considered before 

other weed treatments are implemented. 

Several insect species are permitted for release in the 

United States as biocontrol agents for both Dalmatian and 

yellow toadflaxes. Table 3 lists biocontrol agents approved 

for release in the U.S.; however, the long-term success of 

these agents in the Southwest is largely unknown. For 

further information on biocontrol of Dalmatian and yellow 

toadflaxes, see Sing et al. (2016) in the “References and 

Further Information” section of this field guide. 

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Table 3. Biocontrol agents approved for Dalmatian and yellow toadflaxes 

Species Type of 

Agent Site of Attack Impact Use/Considerations for 

Release 

Brachypterolus beetle Dalmatian and Adults feed on shoot tips and axillary buds; lays An accidental introduction in the 

pulicarius yellow toadflax: 

shoots and flowers 

eggs in buds; larvae feed on immature seeds. Can 

reduce seed set by 74 percent. 

USA, it is approved for 

redistribution within North 

America. Because the beetle is 

already widespread and its 

overall impact is low, it is not a 

high priority for redistribution. 

Eteobalea 

intermediella and 

E. serratella 

moth Both toadflaxes: 

roots 

Adults lay eggs in lower leaf axils at base of yellow 

toadflax and on non-flowering Dalmatian toadflax 

stems. Larvae bore into stem or root. 

Impacts both toadflaxes. 

Mecinus weevil Yellow toadflax: Repeated, yearly attack by both adults and larvae While currently not widely 

janthinus stem mining can lead to striking reductions in toadflax plant 

density. Adult weevils consume/chew on the 

growing tips of toadflax shoots, stems, and leaves, 

producing a distinctive shot hole injury pattern. This 

damage weakens the plant, suppresses flowering and 

seed production, and severely stunts shoots. Larval 

mining causes desiccation and likely depletes 

nutrient reserves in the roots. 

distributed, M. janthinus 

densities and impact on yellow 

toadflax can be high locally; 

this species appears to establish 

well in new areas. 

Mecinus weevil Dalmatian Repeated, yearly attack by both adults and larvae M. janthiniformis is currently 

janthiniformis toadflax: stem 

mined 

can lead to striking reductions in toadflax plant 

density. Adult weevils consume/chew on the 

growing tips of toadflax shoots, stems, and leaves, 

producing a distinctive shot hole injury pattern. This 

damage weakens the plant, suppresses flowering and 

seed production, and severely stunts shoots. Larval 

mining causes desiccation and likely depletes 

nutrient reserves in the roots. 

Large aggregations of M. janthiniformis adults 

feeding on new shoot growth can result in 

significant injury to shoot tips and leaves; heavily 

attacked shoot tips may turn brown and shrivel. 

established in northwestern US 

where it has dramatically 

reduced Dalmatian toadflax 

populations in some locations. 

Rhinusa weevil Dalmatian and Adults eat leaf buds, young leaves, and young shoot This beetle (yellow toadflax 

antirrhini yellow toadflax: tips. After bloom, adults eat floral tissue and lay biotype) was unintentionally 

(formerly seed capsule eggs in floral ovaries; larvae eat seeds. introduced. It has spread 

Gymnaetron) throughout North America on 

both toadflaxes. 

Rhinusa neta weevil Dalmatian and Similar to R. antirrhini. Both species impact seed This beetle was unintentionally 

(formerly yellow toadflax: production and may reduce toadflax by 85 to 90 introduced and is now 

Gymnaetron) seed capsule percent. established in North America, 

but only in scattered 

populations. 

Rhinusa linariae weevil Yellow toadflax: Adult foliage feeding and larval galling are known To date, R. linariae is 

(formerly root to reduce plant nutrient reserves; however, current established only on yellow 

Gymnaetron) populations are too low to have a significant impact 

on yellow toadflax populations. 

toadflax in British Columbia. 

Since populations are slow to 

build, redistributions are made 

whenever possible. 

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Organisms (insects, pathogens, etc.) used as biocontrol 

agents in southwestern States should be adaptable to arid 

environments and local conditions. Public, tribal, and 

private land managers may obtain biocontrol agents for 

release directly from local offices of the USDA Animal 

and Plant Health Inspection Service (APHIS) when these 

agents are available. Other sources for biocontrol agents 

include locally developed insectaries or private companies. 

A permit must be obtained from APHIS before biocontrol 

agents can be transported across State lines. Regulations 

and permit applications (PPQ 526 permit forms) pertaining 

to interstate shipment of biocontrol agents can be found at 

https://www.aphis.usda.gov/aphis/ourfocus/planthealth/im 

port-information/permits/regulated-organism-and-soilpermits/sa_apply/ct_plantpest_howtoapply. Although 

biocontrol agents may be collected and released internally 

in a given State without an APHIS permit, the State’s 

department of agriculture or agricultural extension service 

should be consulted for any regulations relating to 

movement of these agents within the State. 

Chemical Control 

Herbicides recommended in table 4 will control or 

suppress Dalmatian or yellow toadflax s when properly 

applied, although these herbicides may also impact nontarget species such as forbs, shrubs, or trees. Control 

results will vary due to weather variables and the plant’s 

growth stage, so special care should be taken to follow 

label directions closely. Each herbicide product will have 

different and unique requirements and restrictions 

according to the herbicide label. Read and understand the 

label prior to any application. Consult the registrant if you 

have questions or need further details. 

The best performing herbicides for toadflax control are 

chlorsulfuron (e.g., Telar® XP) and picloram (e.g., 

Tordon® 22K) either alone or in combination. Other 

herbicides in table 4 will control toadflax, but plants often 

recover from a single treatment so anticipate that spraying 

may need to be repeated. Research of herbicide effects on 

Dalmatian toadflax in Colorado and Wyoming showed that 

Telar® XP applied at 2 oz/acre gave excellent control over 

5 years while Tordon® 22K at 2 pt./acre gave good 

control. Treatments made on yellow toadflax were 

somewhat site dependent and required higher rates of 

Telar® XP (2.5 to 3 oz/a) or Tordon® 22K (2 to 4 pt/acre) 

to be effective. When mixing Telar® XP, use a quality 

nonionic surfactant (NIS) or silicone-based adjuvant at the 

labeled rate. Control of yellow toadflax with Telar® XP 

may be improved by using methylated seed oil at 1 percent 

v/v instead of a NIS, but injury to native forbs and shrubs 

may increase. 

Herbicide Application 

Most herbicide treatments are recommended for 

application during the flowering or post-flowering stage in 

fall. Yellow toadflax is usually more difficult to control 

with herbicide than Dalmatian toadflax; however, repeated 

treatments over several years are often needed to control 

either species. 

Herbicides shown in table 4 may be applied by backpack 

or hand-held sprayers, ATV or UTV sprayers, or 

conventional boom sprayers that are pulled or attached to a 

tractor or truck. Any equipment used to spray herbicide 

should be calibrated. For individual plant treatment (IPT), 

use a single nozzle on a backpack or hand-held sprayer to 

wet the foliage and stems thoroughly. Consult the 

herbicide label for mixing directions. Herbicides listed in 

table 4 will impact desirable species; therefore, 

precautionary measures should be taken if non-target 

species need protection. 

Management Strategies 

The seedling is the most vulnerable stage for toadflaxes, 

and seedlings should be removed upon discovery. Control 

of established toadflax populations should focus first on 

smaller infestations in otherwise healthy sites. Initial 

toadflax treatments should attempt to eliminate live plants 

and disrupt seed and/or root production as much as 

possible. Later treatments should try to enhance the 

establishment and competition of native plants to further 

reduce toadflax populations. 

A detailed management plan should be developed for sites 

infested with toadflax that considers both the combination 

of methods necessary for toadflax control as well as the 

condition and composition of native plants. Before 

spraying herbicide, evaluate each site closely to determine 

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whether seeding will be necessary or if the plant 

community will return naturally. Seeding is not 

typically needed when native grasses are common 

beneath toadflax, as grasses will increase rapidly in the 

following seasons after treatment. If seeding is needed 

after a spray treatment, then additional herbicide 

treatment can be used to complement seeding of 

desirable competitive species. 

Follow-up monitoring and spot treatment of toadflax 

regrowth and seedlings should be anticipated for at least 

3 to 4 years and possibly longer if complete eradication 

of toadflax is desired. Since it is ordinarily useless to 

treat an area only one time without retreatment, 

sufficient resources must be allocated for the area where 

Table 4. Herbicide recommendations 

Common Chemical 

Name (active 

ingredient) 

Product 

Example1 

Broadcast 

Treatment 

(rate per acre) 

Spot Treatment 

(spray solution) 2 

Time of 

Application Remarks 

Picloram3 Tordon 22K 1–2 quarts 0.5–1% Late flower to 

post-bloom stage 

in the fall. 

Persistent, selective 

herbicide. Re-treatment 

for several years may be 

required. Labeled for 

rangeland use. 

Dicamba Banvel, 

Clarity, 

Vanquish 

1–2 quarts 3–5% Same as above. Same as above 

Chlorsulfuron Telar XP 2–2.6 ounces Consult label Same as above. Apply as a high volume 

foliar spray using a 

minimum of 24 gallons of 

water per acre. 

Aminocyclopyrachlor + 

chlorsulfuron 

Perspective 7.5–8 ounces Add 5–9 grams of dry 

flowable powder to 1 

gallon of water. 

Consult label for 

directions. 

Apply to fall 

rosettes for best 

control. 

Persistent; selective; may 

cause temporary injury to 

some grass species. 

Labeled for non-crop use. 

Imazapic Plateau 8–12 fluid ounces 

Plateau + 1 quart 

methylated seed oil 

(MSO) 

0.25–1.5% Same as above. Persistent, selective 

herbicide. Re-treatment 

for several years may be 

required. Use lower rate 

when cool season grasses 

are present. 

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 toadflaxes. 

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. 

3 Picloram is a restricted-use pesticide. A certified applicator’s license is required for purchase and use. 

control is attempted. After initial treatment, it is 

important that resources are also available to respray or 

retreat the treated area as necessary. Previously treated 

areas should always be continuously monitored and 

retreated when necessary. Failure to perform follow-up 

management may result in re-colonization and a return 

of the infestation to pretreatment levels. 

Adaptive Management 

Because toadflax species are difficult to control, it 

should be anticipated that ongoing management will be 

required for many years. Therefore, realistic goals and 

objectives should be established to manage toadflax 

infestations occurring extensively throughout a given 

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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 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 

Butler, M.D. and L.C. Burrill. 1994. Yellow Toadflaxand 

Dalmatian Toadflax. A Pacific Northwest Extension 

Publication PNW135. Available at 

http://weeds.nmsu.edu/pdfs/yellow_toadflax_ 

factsheet_11-06-05.pdf (accessed May 2010). 

Cardina, J., C. Hern, T. Koch, and T. Webster. Undated. 

Ohio Perennial and Biennial Weed Guide. 

Published by Ohio State University Extension. 

Available at http://www.oardc.ohio-state.edu/ 

weedguide/default.asp (accessed April 2010). 

Davison, J.C., E. Smith, and L.M. Wilson. 2007. Livestock 

Grazing Guidelines for Controlling Noxious Weeds 

in the Western United States. Publication EB-06-05. 

Available at http://www.cnr.uidaho.edu/rx-grazing/ 

Livestock_Graizng_Guidelines%28Davison_et_al.% 

202007%29.pdf (accessed May 2010). 

Douglas County Weed Division. 2005. Integrated Weed 

Management of Dalmatian Toadflax.Castle Rock, 

CO. Available athttp://www.douglas.co.us/ 

publicworks/operations/documents/DalmationToadfl 

ax.pdf (accessed May2010). 

Duncan, K., K. McDaniel, and M. Renz 2005. Chemical 

Weed and Brush Control for New Mexico 

Rangelands. Las Cruces: New Mexico State Univ. 

College of Agriculture and Home Economics and 

Cooperative Extension Service. Pp. 6. Available at 

http://aces.nmsu.edu/pubs/_circulars/CR_597.pdf. 

Hansen, R. Dalmatian and Yellow Toadflax. 1997. In C.R. 

Weeden, A.M. Shelton, and M.P. Hoffman. 1997. 

Biological Control: A Guide to Natural Enemies in 

North America. Cornell University, NY. Available 

at http://www.nysaes.cornell.edu/ent/biocontrol/ 

weedfeeders/toadflax.html (accessed May 2010) 

Invasive Plant Atlas of the United States. Available at 

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

(accessed May 2010). 

Jeffries, A. Undated. Toadflax Control Methods inthe 

Methow Valley. Methow Valley Citizens Council 

Projects. Available at http://www.methow-valleycitizens-council.org/projects/LIDA/lida.htm 

(accessed May 2010). 

Ogden, J.A.E. and M.J. Renz. 2005. DalmatianToadflax 

(Linaria genistifolia ssp. dalmatica). New Mexico 

State Univ. Department of Plant Extension Sciences, 

Las Cruces, NM. Available at 

http://weeds.nmsu.edu/pdfs/dalmatian_toadflax 

_factsheet_11-06-05.pdf (accessed May 2010). 

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Ogden, J.A.E. and M.J. Renz. 2005. Yellow Toadflax 

(Linaria vulgaris) New Mexico State University 

Department of Plant Extension Sciences, Las 

Cruces, NM. Available at http://weeds.nmsu.edu/ 

pdfs/yellow_toadflax_factsheet_11-06-05.pdf 

(accessed May 2010). 

Sing, S., R. De Clerck-Floate, R. Hansen, H. Pearce, C. 

Bell Randall, I. Tosevski, and S. Ward. 2016. 

Biology and Biological Control of Dalmatian and 

Yellow Toadflax (3rd ed.). FHTET-2016-

01.USDA NRCS. 2010. The PLANTS Database. 

National Plant Data Center, Baton Rouge, LA. 

Available athttp://plants.usda.gov (accessed 25 

May 2010). 

Whitson, T.D. (ed.), et al. Weeds of the West. Western 

Society of Weed Science in cooperation with 

Cooperative Extension Services. University of 

Wyoming, Laramie, WY. Available at 

http://plants.usda.gov/java/invasiveOne?pubID=W 

SWS (accessed March 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. Dept. of the 

Interior, Washington, DC. Available at: 

https://www2.usgs.gov/sdc/doc/DOI-

%20Adaptive%20ManagementTechGuide.pdf 

Zouhar, K. 2003. Linaria spp. In Fire Effects Information 

System (Online). U.S. Department ofAgriculture, 

Forest Service, Rocky Mountain Research Station, 

Fire Sciences Laboratory (Producer). Availableat 

http://www.fs.fed.us/database/feis/ (accessed May 

26, 2010). 

Suggested Web Sites 

Encycloweedia Datasheets by California Department of 

Food and Agriculture: http://www.cdfa.ca.gov/ 

phpps/ipc/weedinfo/linaria.htm 

For information about calibrating spray equipment: 

NMSU Cooperative Extension Service Guide A613, Sprayer Calibration. Available at 

http://aces.nmsu.edu/pubs/_a/A613 

Herbicide labels online: http://www.cdms.net/ 

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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.