Species Brief
Scutellaria mexicana, Mexican bladdersage
Written
July, 2026
Contributors
Taryn R. Brahmsteadt - 1st Compiler, Ilana L. Abrahamson - 1st Editor
Brahmsteadt, Taryn R., compiler. 2026. Species Brief: Scutellaria mexicana, Mexican bladdersage. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Missoula Fire Sciences Laboratory (Producer). Available: https://research.fs.usda.gov/feis/species-reviews/scumex
DOI
10.2737/feis-species-brief-scumex
Scientific Name
Scutellaria mexicana
Common Names
Mexican bladdersage
paperbag bush
bladder sage
FEIS Lifeform Type
Shrub
Subshrub
Kingdom
Plantae
Class
Magnoliopsida (Dicot)
Order
Lamiales
Family
Lamiaceae
Genus
Scutellaria
Nativity
Native
Invasiveness
Noninvasive
This Species Brief is a concise summary of the biological, ecological, and fire‑related characteristics of an individual species derived from a Fire Effects Information System (FEIS) Species Review. Table 1 is derived from a standardized template and highlights these characteristics.
| Attribute | Characteristic | Justification | Source |
|---|---|---|---|
| Biological characteristics | |||
| Life form | Shrub; Subshrub | Mexican bladdersage is a perennial shrub that grows up to 2 m tall. It sometimes grows as a subshrub. | FEIS: Botanical Description [1] |
| Typical lifespan | Insufficient information | The source describes Mexican bladdersage variously as a short-lived pioneer, an intermediate-lived shrub, and a long-lived shrub, and gives no quantified typical lifespan. It shares traits generally found in short- or intermediate-lived shrubs. | FEIS: Plant Growth and Mortality [1] |
| Life cycle | Perennial | Mexican bladdersage is a perennial shrub. | FEIS: Botanical Description [1] |
| Drought tolerance | High | Mexican bladdersage is drought-tolerant, though extended drought may cause high mortality. | FEIS: Site Characteristics [1] |
| Rooting depth | Shallow* | Mexican bladdersage arises from intricately branched, narrow rhizomes that spread close to the soil surface; no deeper roots are described, so the shallow rating reflects the rhizome system. | FEIS: Belowground Description [1] |
| Bark thickness at maturity | N/A | This attribute applies to trees. | FEIS: Botanical Description [1] |
| Sheds low branches | N/A | This attribute applies to trees. | FEIS: Botanical Description [1] |
| Reproduction and Regeneration | |||
| Adventitious buds | Rhizomes | Mexican bladdersage reproduces and spreads from rhizomes and can resprout and spread from rhizomes after disturbances that top-kill or injure it. | FEIS: Vegetative Reproduction and Regeneration [1] |
| Time to reproductive maturity | 2-5 years | Mexican bladdersage begins producing flowers and fruits when it is 2 to 3 years old. | FEIS: Seed Production and Predation [1] |
| Soil seed bank longevity | Long-term persistent (>5 years)* | Field observations about seed banking are lacking. Viability of stored seeds decreases rapidly between the first and second year and then decreases steadily, nearing 0% after 11.5 years, suggesting some seeds persist beyond 5 years though field longevity is uncertain. | FEIS: Seed Banking and Germination [1] |
| Serotinous cones | N/A | This attribute applies to conifers. Mexican bladdersage produces seeds enclosed within papery, inflated calyces. | FEIS: Seed Dispersal [1] |
| Seed dispersal mechanism | Wind | Mexican bladdersage seeds are enclosed within papery, inflated calyces, which are dispersed by wind. | FEIS: Seed Dispersal [1] |
| Seed dispersal distance | Medium*; Long (>1 km) | Mexican bladdersage is an opportunistic colonizer characterized by long-distance seed dispersal by wind. Seedlings may establish in burns from seed that dispersed onto the sites from long distances by wind. However, some seeds will disperse closer to the parent plant. | FEIS: Seed Dispersal; Seedling Establishment and Mortality [1] |
| Optimal conditions for seedling establishment | Sun* | There is little information about Mexican bladdersage seedling establishment. One study found that 9 of 45 seedlings planted into full sun on a rocky hard clay ridge survived 6 years later. Mexican bladdersage dominates in frequently disturbed warm desert arroyo, wash, and upland communities, where it is likely very sunny. | FEIS: Seedling Establishment and Mortality [1] |
| Successional Status | |||
| Shade tolerance | Shade intolerant* | The source does not provide explicit information about Mexican bladdersage shade tolerance. Mexican bladdersage grows in many communities with an open shrub layer and no overstory, and it often dominates in habitats with regular disturbance. | FEIS: Plant Communities; Successional Status [1] |
| Successional status | Early; Mid*; Late* | Mexican bladdersage is classified as an early-successional pioneer species, although it also grows in undisturbed and late-successional communities. | FEIS: Successional Status [1] |
| Fire | |||
| Primary fire response(s) or adaptation(s) | Recover/Resprout; Recruit | Fire typically top-kills Mexican bladdersage, after which abundance may increase by resprouting from rhizomes or by prolific seedling establishment from wind-dispersed off-site seed. | FEIS: Immediate Fire Effects; Plant Response to Fire [1] |
| Germination is fire stimulated | Rarely/No* | After fire, seedling establishment is attributed to off-site wind-dispersed seed rather than a fire germination cue. No studies of fire effects on germination were available; however, seeds are not dormant, making it unlikely that fire stimulates germination. | FEIS: Seed Banking and Germination; Plant Response to Fire [1] |
| Flowering/fruiting is fire stimulated | Insufficient information | The source does not provide explicit information about fire-stimulated flowering or fruiting. | FEIS: Entire [1] |
| Season when it is most sensitive to fire | Insufficient information | Information about Mexican bladdersage's response to fire is limited and largely anecdotal. Information was not available about sensitivity to fire by season. | FEIS: Entire [1] |
| Plant flammability | High | Aboveground parts of Mexican bladdersage are often consumed by fire because of their relatively small size, fine branching, and high horizontal and vertical fuel continuity. | FEIS: Fuel Characteristics [1] |
| Early colonizer/recolonizer of burned or disturbed sites | Frequently* | Mexican bladdersage is an opportunistic colonizer that may dominate early- to mid-successional stands after fire, but its postfire response varies and abundance does not always increase, so colonization is not consistent across sites. | FEIS: Great Basin Pinyon-Juniper Woodland Group; Plant Response to Fire [1] |
| Effect of fire exclusion on population | N/A | Fire intervals are are estimated to exceed several centuries in most communities where Mexican bladdersage occurs, and fire exclusion has not occurred on a time scale that is relevant to these communities. | FEIS: Fire Regimes; Entire [1] |
| Is this species typically managed with prescribed fire? | Rarely/No | Fire is generally considered harmful to the desert scrub communities where Mexican bladdersage occurs, and management emphasizes fire prevention rather than prescribed burning. | FEIS: Fire Management Considerations [1] |
| Predominant historical fire frequencies of ecosystem where it most commonly occurs | Infrequent | The warm desert scrub communities where Mexican bladdersage is common or dominant historically had stand-replacing fires at long intervals and are fuel-limited in most years, with insufficient fine fuel to carry fire. | FEIS: Fire Regimes; Fuel Characteristics [1] |
| Predominant historical fire severity where it most commonly occurs | Replacement | Historical fire regimes in these communities are characterized by stand-replacing fires, and the LANDFIRE biophysical settings list replacement-severity fire as the predominant or sole severity class for the desert wash and mixed-desert-scrub communities Mexican bladdersage dominates. | FEIS: Fire Regimes; 2020 LANDFIRE Biophysical Settings [1] |
| Predominant historical fire regime group where it most commonly occurs | 5 | Mexican bladdersage most commonly dominates desert wash scrub and Mojave mid-elevation mixed desert scrub, whose LANDFIRE settings are group V-A or V-B (long intervals, replacement severity) — consistent with fire regime group 5. | FEIS: 2020 LANDFIRE Biophysical Settings [1] |
| Alters historical fuel characteristics of ecosystems where it occurs | Rarely/No | Contemporary shifts in fuel and fire-regime characteristics are attributed primarily to the introduction and spread of invasive grasses, not to Mexican bladdersage, which is native and historically grew in fuel-limited communities. | FEIS: Fire Regimes [1] |
| Biophysical Setting | Mean Fire Interval (years) | Fire Severity Percent (%) | ||||||
|---|---|---|---|---|---|---|---|---|
| Code | Fire Regime Group | Low | Mixed | Replacement | All | Low | Mixed | Replacement |
| Series 10190 - Great Basin Pinyon-Juniper Woodland | ||||||||
| 10190_13_14 | III-B | 780 | 337 | 474 | 157 | 20 | 47 | 33 |
| 10190_15 | III-B | 765 | 335 | 475 | 156 | 20 | 47 | 33 |
| 10190_4 | V-A | 814 | 467 | 640 | 203 | 25 | 43 | 32 |
| 10190_6_7_9_12_16_17_18_19 | V-A | 898 | 865 | 440 | 0 | 49 | 51 | |
| Series 10780 - Colorado Plateau Blackbrush-Mormon-tea Shrubland | ||||||||
| 10780_15 | V-A | 282 | 282 | 0 | 0 | 100 | ||
| Series 10820 - Mojave Mid-Elevation Mixed Desert Scrub | ||||||||
| 10820_12_15_16_17_23_24 | V-B | 815 | 815 | 0 | 0 | 100 | ||
| 10820_14 | V-A | 406 | 406 | 0 | 0 | 100 | ||
| 10820_4_13 | V-A | 399 | 399 | 0 | 0 | 100 | ||
| Series 11290 - California Central Valley and Southern Coastal Grassland | ||||||||
| 11290_4_5 | II-A | 4 | 4 | 0 | 0 | 100 | ||
| Series 11552 - North American Warm Desert Riparian Systems - Stringers | ||||||||
| 11552_13_14_15 | V-B | 735 | 735 | 0 | 0 | 100 | ||
| Series 10870 - Sonora-Mojave Creosotebush-White Bursage Desert Scrub | ||||||||
| 10870_4_6_12_13_14_15_17_24_25 | V-A | 329 | 329 | 0 | 0 | 100 | ||
| Summary | ||||||||
| Minimum | 765 | 335 | 4 | 4 | 0 | 0 | 32 | |
| Maximum | 814 | 898 | 865 | 815 | 25 | 49 | 100 | |
| Mean | 786 | 509 | 493 | 357 | 6 | 17 | 77 | |
| Median | 780 | 402 | 474 | 329 | 0 | 0 | 100 | |
| Percentage of fires in 3 fire severity classes, derived from LANDFIRE succession modeling. Replacement-severity fires cause >75% kill or top-kill of the upper canopy layer; mixed-severity fires cause 26%-75%; low-severity fires cause <26%. | ||||||||
| LANDFIRE. 2020. Biophysical settings models and descriptions, [Online]. Washington, DC: U.S. Department of Agriculture, Forest Service; U.S. Department of the Interior; U.S. Geological Survey; Arlington, VA: The Nature Conservancy, (Producers). Available: https://www.landfirereview.org/search.php [96496] | ||||||||
1. Brahmsteadt, Taryn R. 2024. Scutellaria mexicana, Mexican bladdersage. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Missoula Fire Sciences Laboratory (Producer). Available: https://research.fs.usda.gov/feis/species-reviews/scumex
Last updated August 24, 2026