Plant Assessment Form

More Linaria dalmatica ssp. dalmatica resources

Linaria dalmatica ssp. dalmatica

Synonyms: Linaria genistifolia ssp. dalmatica, Linaria dalmatica, Linaria dalmatica ssp. dalmatica, Antirrhimum dalmaticum

Common Names: Dalmatian toadflax, broad-leaved toadflax, wild snapdragon

Evaluated on: 1/27/05

List committee review date: 08/07/2005

Re-evaluation date:

Evaluator(s)

Elizabeth Brusati, project manager
California Invasive Plant Council
1442A Walnut St. #462, Berkeley, CA 94709
510-843-3902
edbrusati@cal-ipc.org

Joseph DiTomaso
University of California-Davis
Dept. Plant Sci., Mail Stop 4, Davis, CA 95616
530-754-8715
jmditomaso@ucdavis.edu

List committee members

Joe DiTomaso
Alison Stanton
Joanna Clines
Cynthia Roye
Doug Johnson

General Comments

Removed second scientific name, Linaria genistifolia ssp. dalmatica, and added it to the synonym line, 3/24/17. Ramona Robison

Table 2. Criteria, Section, and Overall Scores

Overall Score? Moderate

Alert Status? No Alert

Documentation? 3 out of 5

Score

Documentation

1.1

?Impact on abiotic ecosystem processes

B. Moderate

Reviewed Scientific Publication

Impact?
Four-part score BBBU Total Score
B

1.2

?Impact on plant community

B. Moderate

Reviewed Scientific Publication

1.3

?Impact on higher trophic levels

B. Moderate

Other Published Material

1.4

?Impact on genetic integrity

U. Unknown

2.1

?Role of anthropogenic and natural disturbance in establishment

B. Moderate

Other Published Material

Invasiveness?
Total Points
12 Total Score B

2.2

?Local rate of spread with no management

A. Increases rapidly

Other Published Material

2.3

?Recent trend in total area infested within state

B. Increasing less rapidly

Observational

2.4

?Innate reproductive potential
(see Worksheet A)

A. High

Reviewed Scientific Publication

2.5

?Potential for human-caused dispersal

C. Low

Other Published Material

2.6

? Potential for natural long-distance dispersal

D. None

Other Published Material

2.7

?Other regions invaded

C. Already invaded

Other Published Material

3.1

?Ecological amplitude/Range
(see Worksheet C)

A. Widespread

Other Published Material

Distribution?
Total Score B

3.2

?Distribution/Peak frequency
(see Worksheet C)

D. Very low

Observational

Table 3. Documentation

Scores are explained in the "Criteria for Categorizing Invasive Non-Native Plants that Threaten Wildlands".

Section 1: Impact
Question 1.1 Impact on abiotic ecosystem processes? Consider the impact on the natural range and variation of abiotic ecosystem processes and system-wide parameters in ways that significantly diminish the ability of native species to survive and reproduce. Alterations that determine the types of communities that can exist in a given area are of greatest concern. Examples of abiotic processes include: - fire occurrence, frequency, and intensity; - geomorphological changes such as erosion and sedimentation rates; - hydrological regimes, including soil water table; - nutrient and mineral dynamics, including salinity, alkalinity, and pH; - light availability (e.g. when an aquatic invader covers an entire water body that would otherwise be open). Select the one letter below that best describes this species' most severe impact on an abiotic ecosystem process: A. Severe, possibly irreversible, alteration or disruption of an ecosystem process. B. Moderate alteration of an ecosystem process. C. Minor alteration of an ecosystem process. D. Negligible perceived impact on an ecosystem process. U. Unknown.	B Reviewed Scientific Publication
Identify ecosystem processes impacted: Plants are highly competitive for soil moisture. Sources of information: Rose, K. K., A. L. Hild, T. D. Whitson, D. W. Koch, and L. Van Tassel. 2001. Competitive effects of cool-season grasses on re-establishment of three weed species. Weed Technology 15(4): 885-891
Question 1.2 Impact on plant community composition, structure, and interactions? Consider the cumulative ecological impact of this species to the plant communities it invades. Give more weight to changes in plant composition, structure, and interactions that involve rare or keystone species or rare community types. Examples of severe impacts include: - formation of stands dominated (>75% cover) by the species; - occlusion (>75% cover) of a native canopy, including a water surface, that eliminates or degrades layers below; - significant reduction or extirpation of populations of one or more native species. Examples of impacts usually less than severe include: - reduction in propagule dispersal, seedling recruitment, or survivorship of native species; - creation of a new structural layer, including substantial thatch or litter, without elimination or replacement of a pre-existing layer; - change in density or depth of a structural layer; - change in horizontal distribution patterns or fragmentation of a native community; - creation of a vector or intermediate host of pests or pathogens that infect native plant species. Select the one letter below that best describes this species' impact on community composition, structure and interactions: A. Severe alteration of plant community composition, structure, or interactions. B. Moderate alteration of plant community composition. C. Minor alteration of community composition. D. Negligible impact known; causes no perceivable change in community composition, structure, or interactions. U. Unknown.	B Reviewed Scientific Publication
Identify type of impact or alteration: Displaces existing plant communities through vegetative reproduction. Highly efficient in competing for moisture and usually emerges before competing species (1). Seedlings are less successful where dense stands of grasses are present, but this may not be very important as most of its competitive ability comes from the spread of roots. Plants are highly competitive for soil moisture with winter annuals and shallow-rooted perennials, and large colonies that displace desirable vegetation can develop in natural areas. The toadflaxes are especially problematic in the northwestern states, where thousands of acres of rangeland are heavily infested. Production of dalmation toadflax declines as seeded grasses increase (2). Plant competition was the main factor influencing seedling counts, suggesting that recruitment of Dalmation toadflax is limited by interspecific resource competition (3). Sources of information: 1. Lajeunesse, S. 1999. Dalmatian and yellow toadflax. pp. 202-216 in Sheley, R.L., and J. K. Petroff. Biology and management of noxious rangeland weeds. Oregon State University Press, Corvallis, OR 2. Rose, K. K., A. L. Hild, T. D. Whitson, D. W. Koch, and L. Van Tassel. 2001. Competitive effects of cool-season grasses on re-establishment of three weed species. Weed Technology 15(4): 885-891 3. Grieshop, M. J. and R. M. Nowierski . 2002. Selected factors affecting seedling recruitment of dalmatian toadflax. Journal of Range Management 55(6): 612-619.
Question 1.3 Impact on higher trophic levels? Consider the cumulative impact of this species on the animals, fungi, microbes, and other organisms in the communities that it invades. Although a non-native species may provide resources for one or a few native species (e.g. by providing food, nesting sites, etc.), the ranking should be based on the species' net impact on all native species. Give more weight to changes in composition and interactions involving rare or keystone species or rare community types. Examples of severe impacts include: - extirpation or endangerment of an existing native species or population; - elimination or significant reduction in native species' nesting or foraging sites, cover, or other critical resources (i.e., native species habitat), including migratory corridors. Examples of impacts that are usually less than severe include: - minor reduction in nesting or foraging sites, cover, etc. for native animals; - minor reduction in habitat connectivity or migratory corridors; - interference with native pollinators; - injurious components, such as awns or spines that damage the mouth and gut of native wildlife species, or production of anti-digestive or acutely toxic chemical that can poison native wildlife species. Select the one letter below that best describes this species' impact on community composition and interactions: A. Severe alteration of higher trophic populations, communities, or interactions. B. Moderate alteration of higher trophic level populations, communities, or interactions. C. Minor alteration of higher trophic level populations, communities or interactions. D. Negligible impact; causes no perceivable change in higher trophic level populations, communities, or interactions. E. Unknown.	B Other Published Material
Identify type of impact or alteration: Loss of forage can impact big-game species. Deer browse dalmation toadflax, but it is not know to be heavily used by any native species (1). Livestock typically avoid grazing toadflax; thus, livestock carrying capacity is much reduced in areas where there are large, dense populations of toadflax. Both species contain quinazoline alkaloids that could possibly pose toxicity problems if ingested in sufficient quantity, but intoxications of livestock have not been reported. Sources of information: 1. Lajeunesse 1999 DiTomaso and Healy. 2006. Weeds of California. UC DANR Publ. #3488.
Question 1.4 Impact on genetic integrity? Consider whether the species can hybridize with and influence the proportion of individuals with non-native genes within populations of native species. Mechanisms and possible outcomes include: - production of fertile or sterile hybrids that can outcompete the native species; - production of sterile hybrids that lower the reproductive output of the native species. Select the one letter below that best describes this species' impact on genetic integrity: A. Severe (high proportion of individuals). B. Moderate (medium proportion of individuals). C. Minor (low proportion of individuals). D. No known hybridization. U. Unknown.	U
There is one native (L. canadensis, blue toadflax) and several introduced species of Linaria in California (1). A hybrid between L. dalmatica and L. vulgaris was found in Modoc County (2), so presumably it could also hybridize with L. canadensis. Sources of information: 1. Hickman, J. C. (ed.) 1993. The Jepson Manual, Higher Plants of California. University of California Press. Berkeley, CA 2. Vujnovic K., and R.W. Wein R.W. 1997. The Biology of Candadian Weeds. 106. Linaria dalmatica (L.) Mill. Canadian Journal of Plant Science 77(3): 483-401.
Section 2: Invasiveness
Question 2.1 Role of anthropogenic and natural disturbance in establishment? Assess this species' dependence on disturbance: both human and natural: for establishment in wildlands. Examples of anthropogenic disturbances include: - grazing, browsing, and rooting by domestic livestock and feral animals; - altered fire regimes, including fire suppression; - cultivation; - silvicultural practices; - altered hydrology due to dams, diversions, irrigation, etc.; - roads and trails; - construction; - nutrient loading from fertilizers, runoff, etc. Examples of natural disturbance include: - wildfire; - floods; - landslides; - windthrow; - native animal activities such as burrowing, grazing, or browsing. Select the first letter in the sequence below that describes the ability of this species to invade wildlands: A. Severe invasive potential: this species can establish independent of any known natural or anthropogenic disturbance. B. Moderate invasive potential: this species may occasionally establish in undisturbed areas but can readily establish in areas with natural disturbances. C. Low invasive potential: this species requires anthropogenic disturbance to establish. D. No perceptible invasive potential: this species does not establish in wildlands (though it may persist from former cultivation). U. Unknown.	A Other Published Material
Describe role of disturbance: All papers describe it as occurring in disturbed habitats, but it is frequently invading undisturbed sites. Many populations have evolved with, and are adapted to, periodic disturbances of agriculture. Can also establish in naturally-occurring disturbances (1). In California, occurs in a range of disturbed areas (see 3.1). In Washington, dalmation toadflax seedings were never found on non-cultivated areas, indicating it may be unable to become established in heavy stands of vegetation (2). See also question 1.2. Sources of information: 1. Lajeunesse 1999 2. Gates D.H., Robocker W.C. 1961?. Revegetation with adapted grasses in competition with dalmation toadflax and St. Johnswort. Scientific Paper 1943, Washington Agricultural Experiment Station, Pullman, WA
Question 2.2 Local rate of spread with no management? Assess this species' rate of spread in existing localized infestations where the proportion of available habitat invaded is still small when no management measures are implemented. Select the one letter below that best describes the rate of spread: A. Increases rapidly (doubling in <10 years) B. Increases, but less rapidly C. Stable D. Declining U. Unknown	A Other Published Material
Describe rate of spread: Can expand at a rapid rate in many locations of the west, including California. Sources of information: DiTomaso and Healy. 2006. Weeds of California. UC DANR Publ. #3488.
Question 2.3 Recent trend in total area infested within state? Assess the overall trend in the total area infested by this species statewide. Include current management efforts in this assessment and note them. Select the one letter below that best describes the current trend: A. Increasing rapidly (doubling in total range statewide in <10 years) B. Increasing, but less rapidly C. Stable D. Declining U. Unknown	B Observational
Describe trend: Spreading, but not rapidly. Some control efforts by CDFA keep populations down. Sources of information: DiTomaso, observational.
Question 2.4 Innate reproductive potential? Assess the innate reproductive potential of this species. Worksheet A is provided for computing the score.	A Reviewed Scientific Publication
Describe key reproductive characteristics: Deep-rooted, short-lived (3-5 yrs) herbaceaous perennial (1). Insect-pollinated and self-incompatible (2). Individual patches can persist 13 yrs or more. Flowering begins in June and continues until September or October, but can occur earlier in warmer habitats. Within nine weeks after germination, seedling roots have vegetative buds that can give rise to new, independent plants. Roots of mature plants can reach to 10 ft deep (1). Produces seeds for 3 months. A large plant can produce 500,000 seeds. >90% germination can be obtained from 2 or 3-yr-old seeds in the lab. Seed longevity under field conditions can be up to 10 yrs (3). Sources of information: 1. Lajeunesse 1999 2. Vujnovic, K. and R. W. Wein 1997. The biology of Canadian weeds: 106. Linaria dalmatica (L.) Mill. Canadian Journal of Plant Science 77(3): 483-491. 3. Robocker, W. C. 1970. Seed characteristics and seedling emergence of Dalmatian toadflax. [Linaria dalmatica]. Weed Science 18(6): 720-725.
Question 2.5 Potential for human-caused dispersal? Assess whether this species is currently spread: or has high potential to be spread: by direct or indirect human activity. Such activity may enable the species to overcome natural barriers to dispersal that would not be crossed otherwise, or it may simply increase the natural dispersal of the species. Possible mechanisms for dispersal include: - commercial sales for use in agriculture, ornamental horticulture, or aquariums; - use as forage, erosion control, or revegetation; - presence as a contaminant (seeds or propagules) in bulk seed, hay, feed, soil, packing materials, etc.; - spread along transportation corridors such as highways, railroads, trails, or canals; - transport on boats or boat trailers. Select the one letter below that best describes human-caused dispersal and spread: A. High: there are numerous opportunities for dispersal to new areas. B. Moderate: human dispersal occurs, but not at a high level. C. Low: human dispersal is infrequent or inefficient. D. Does not occur. U. Unknown.	C Other Published Material
Identify dispersal mechanisms: Was used as a garden plant, although is not currently listed in the Sunset Western Garden Book (1). On farm land, root pieces can be spread by farm equipment. Seeds can be tranported in mud on bikes, tires, feet of livestock, etc. (2). However, most seed fall directly below parent plant. Sources of information: 1. Brenzel, K. N. 2001. Sunset Western Garden Book. Sunset Publishing Company, Menlo Park, CA. 2. Lajeunesse 1999
Question 2.6 Potential for natural long-distance dispersal? We have chosen 1 km as the threshold of "long-distance." Assess whether this species is frequently spread, or has high potential to be spread, by animals or abiotic mechanisms that can move seed, roots, stems, or other propagules this far. The following are examples of such natural long-distance dispersal mechanisms: - the species' fruit or seed is commonly consumed by birds or other animals that travel long distances; - the species' fruits or seeds are sticky or burred and cling to feathers or hair of animals; - the species has buoyant fruits, seeds, or other propagules that are dispersed by flowing water; - the species has light propagules that promote long-distance wind dispersal; - The species, or parts of it, can detach and disperse seeds as they are blown long distances (e.g., tumbleweed). Select the one letter below that best describes natural long-distance dispersal and spread: A. Frequent long-distance dispersal by animals or abiotic mechanisms. B. Occasional long-distance dispersal by animals or abiotic mechanisms. C. Rare dispersal more than 1 km by animals or abiotic mechanisms. D. No dispersal of more than 1 km by animals or abiotic mechanisms. U. Unknown.	D Other Published Material
Identify dispersal mechanisms: Seeds can be dispersed by wind, but 80-90% of seeds fall within 0.5m of the parent plant (1), so long distance dispersal does not sound common. Sources of information: 1. Lajeunesse 1999
Question 2.7 Other regions invaded? Assess whether this species has invaded ecological types in other states or countries outside its native range that are analogous to ecological types not yet invaded in your state (see Worksheets B, C, and D for California, Arizona, and Nevada, respectively, in Part IV for lists of ecological types). This information is useful in predicting the likelihood of further spread within your state. Select the one letter below that best describes the species' invasiveness in other states or countries, outside its native range. A. This species has invaded 3 or more ecological types elsewhere that exist in your state and are as yet not invaded by this species (e.g. it has invaded Mediterranean grasslands, savanna, and maquis in southern Europe, which are analogous to California grasslands, savanna, and chaparral, respectively). B. Invades 1 or 2 ecological types that exist but are not yet invaded in your state. C. Invades elsewhere but only in ecological types that it has already invaded in the state. D. Not known as an escape anywhere else. U. Unknown.	C Other Published Material
Identify other regions: Native to the Mediterranean. Serious problem in rangeland of the northwestern U.S. Listed as a noxious weed in Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Oregon, South Dakota, Washington, Wyoming (1). Also invasive in Canada, the British Isles, the mideast , and other areas around the world.Dalmatian toadflax and yellow toadflax were brought to North America from Europe as garden ornamentals in the mid- to late-1800s and mid-1600s, respectively, and have since widely escaped cultivation. Sources of information: 1. DiTomaso and Healy. 2006. Weeds of California. UC DANR Publ. #3488.
Section 3: Distribution
Question 3.1 Ecological amplitude/Range? Refer to Worksheet C and select the one letter below that indicates the number of different ecological types that this species invades. A. Widespread: the species invades at least three major types or at least six minor types. B. Moderate: the species invades two major types or five minor types. C. Limited: the species invades only one major type and two to four minor types. D. Narrow: the species invades only one minor type. U. Unknown.	A Other Published Material
Occurs throughout California, except Great Basin and deserts, to 1000m. Grows in disturbed open sites, fields, pastures, rangeland, forest clearings, roadsides, crops. Can tolerate a broad range of climatic conditions and soil types, but grows best in cool, semi-arid climates, and on dry, coarse soils at neutral to slightly alkaline pH. Does NOT occur in the following counties: Amador, Fresno, Imperial, Kings, Marin, Mariposa, Orange, Riverside, San Benito, Santa Clara, Santa Cruz, Stanislaus, Sonoma, Sutter, Tuolumne, Yuba. Sources of information: DiTomaso and Healy. 2006. Weeds of California. UC DANR Publ. #3488.
Question 3.2 Distribution/Peak frequency? To assess distribution, record the letter that corresponds to the highest percent infested score entered in Worksheet C for any ecological type.	D Observational
Describe distribution: Not common in state, mainly found in northern areas. Sources of information: DiTomaso, observational. Joanna Clines, Sierra National Forest, pers. obs.

Worksheet A - Innate reproductive potential

Reaches reproductive maturity in 2 years or less	Yes
Dense infestations produce >1,000 viable seed per square meter	Yes
Populations of this species produce seeds every year.	Yes
Seed production sustained over 3 or more months within a population annually	No
Seeds remain viable in soil for three or more years	Yes
Viable seed produced with both self-pollination and cross-pollination	No
Has quickly spreading vegetative structures (rhizomes, roots, etc.) that may root at nodes	Yes
Fragments easily and fragments can become established elsewhere	No
Resprouts readily when cut, grazed, or burned	Yes
Total points:	8
Total unknowns:	0
Total score:	A? Scoring Criteria for Worksheet A A. High reproductive potential (6 or more points). B. Moderate reproductive potential (4-5 points). C. Low reproductive potential (3 points or less and less than 3 Unknowns). U. Unknown (3 or fewer points and 3 or more Unknowns).

Related traits:

Worksheet B - Arizona Ecological Types is not included here

Worksheet C - California Ecological Types

(sensu Holland 1986)

Major Ecological Types	Minor Ecological Types	Code? A means >50% of type occurrences are invaded; B means 20% to 50%; C means 5% to 20%; D means present but <5%; U means unknown (unable to estimate percentage of occurrences invaded)
Marine Systems	marine systems
Freshwater and Estuarine	lakes, ponds, reservoirs
Aquatic Systems	rivers, streams, canals
Aquatic Systems	estuaries
Dunes	coastal
	desert
	interior
Scrub and Chaparral	coastal bluff scrub
	coastal scrub
	Sonoran desert scrub
	Mojavean desert scrub (incl. Joshua tree woodland)
	Great Basin scrub	D, < 5%
	chenopod scrub
	montane dwarf scrub
	Upper Sonoran subshrub scrub
	chaparral
Grasslands, Vernal Pools, Meadows, and other Herb Communities	coastal prairie
	valley and foothill grassland
	Great Basin grassland	D, < 5%
	vernal pool
	meadow and seep
	alkali playa
	pebble plain
Bog and Marsh	bog and fen
Bog and Marsh	marsh and swamp
Riparian and Bottomland habitat	riparian forest
	riparian woodland
	riparian scrub (incl.desert washes)
Woodland	cismontane woodland
	piñon and juniper woodland
	Sonoran thorn woodland
Forest	broadleaved upland forest
	North Coast coniferous forest
	closed cone coniferous forest
	lower montane coniferous forest	D, < 5%
	upper montane coniferous forest	D, < 5%
	subalpine coniferous forest
Alpine Habitats	alpine boulder and rock field
Alpine Habitats	alpine dwarf scrub
	Amplitude (breadth):	B
	Distribution (highest score):	D

Infested Jepson Regions

Click here for a map of Jepson regions

CA Floristic Province
Cascade Range
Central West
Great Valley
Northwest
Sierra Nevada
Southwest
Great Basin Province
Modoc Plateau
Sierra Nevada East