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Agave schottii

Engelm.

Schott's Century Plant

G4Apparently Secure Found in 15 roadless areas NatureServe Explorer →
G4Apparently SecureGlobal Rank
Least concernIUCN
UnknownThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.133858
Element CodePMAGA010N0
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
IUCNLeast concern
Endemicoccurs (regularly, as a native taxon) in multiple nations
KingdomPlantae
PhylumAnthophyta
ClassMonocotyledoneae
OrderAsparagales
FamilyAsparagaceae
GenusAgave
Other Common Names
Schott's Agave (EN) Schott's century plant (EN)
Concept Reference
Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
Conservation Status
Rank Method Rank calculation - Biotics v2
Review Date2026-01-29
Change Date2026-01-29
Edition Date2026-01-29
Edition AuthorsSoteropoulos (2026)
Threat ImpactUnknown
Range Extent20,000-200,000 square km (about 8000-80,000 square miles)
Number of Occurrences81 - 300
Rank Reasons
Agave schottii is a wide-ranging perennial succulent, forb to shrub found in gravelly to rocky places, mostly in desert scrub, grasslands, juniper and oak woodlands. It occurs in southwestern North America in southern Arizona and southwestern New Mexico in the United States and northern Sonora and northwestern Chihuahua in Mexico. There are over 100 occurrences, which face threats from prolonged droughts that have led to increased fire frequency, with fires leading to plant mortality, and potentially hybridization. Little is known about trends, but with a large range extent and moderate number of occurrences, abundant habitat, and broad habitat preferences, this taxon is considered apparently secure.
Range Extent Comments
Agave schottii occurs in southwestern North America in southern Arizona (Pima, Santa Cruz, Graham, and Cochise counties) and southwestern New Mexico (Hidalgo County) in the United States and northern Sonora and northwestern Chihuahua in Mexico (FNA 2002, Hodgson and Puente 2020). Range extent was estimated to be approximately 50,000 square kilometers using herbarium specimens, photo-based observations, and NatureServe Network occurrence data documented between 1994 and 2025 (AZGFD 2025, RARECAT 2025, GBIF 2026, iNaturalist 2026, SEINet 2026).
Occurrences Comments
By applying a 1 km separation distance to herbarium specimens, photo-based observations, and NatureServe Network occurrence data documented between 1994 and 2025, it is estimated that there are over 100 occurrences rangewide (AZGFD 2025, RARECAT 2025, GBIF 2026, iNaturalist 2026, SEINet 2026).
Threat Impact Comments
Although threats are not widely documented, this taxon is threatened by prolonged droughts that have led to increased fire frequency, with fires leading to plant mortality, and potentially hybridization (with A. deserti var. simplex, A. chrysantha, and possibly A. palmeri or A. parryi var. parryi), though there is insufficient data, including anecdotal accounts, to understand scope and severity of threats for this taxon (FNA 2002, Hodgson et al. 2020).
Ecology & Habitat

Habitat

Agave schottii grows in "gravelly to rocky places, mostly in desert scrub, grasslands, juniper and oak woodlands" (FNA 2002).

Reproduction

This taxon flowers in late spring (May) to late summer (August) (FNA 2002, Wildflower Center 2026). Plants are monocarpic, meaning they flower once in their lifetime and then die. Plants may create colonies; they are freely suckering, creating new individuals at the base of parent plants, though rosettes may be solitary or densely cespitose (FNA 2002).
Terrestrial Habitats
Woodland - HardwoodWoodland - ConiferWoodland - MixedShrubland/chaparralGrassland/herbaceousDesert
Other Nations (1)
United StatesN4
ProvinceRankNative
New MexicoSNRYes
ArizonaS5Yes
Threat Assessments
ThreatScopeSeverityTiming
7 - Natural system modificationsUnknownUnknownHigh (continuing)
7.1 - Fire & fire suppressionUnknownUnknownHigh (continuing)
7.1.1 - Increase in fire frequency/intensityUnknownUnknownHigh (continuing)
8 - Invasive & other problematic species, genes & diseasesUnknownUnknownUnknown
8.3 - Introduced genetic materialUnknownUnknownUnknown
11 - Climate change & severe weatherUnknownUnknownHigh (continuing)
11.2 - DroughtsUnknownUnknownHigh (continuing)

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Plant Characteristics
DurationPERENNIAL
Economic Value (Genus)Yes
Roadless Areas (15)
Arizona (14)
AreaForestAcres
Butterfly Roadless AreaCoronado National Forest42,296
Catalina St. Pk. Roadless AreaCoronado National Forest951
Cdo WsaCoronado National Forest1,955
GaliuroCoronado National Forest28,333
Happy ValleyCoronado National Forest7,972
Horse MesaTonto National Forest9,146
Lower RinconCoronado National Forest3,278
Middle Dragoon RoadlessCoronado National Forest10,543
Oracle RoadlessCoronado National Forest22,365
Santa RitaCoronado National Forest6,078
TumacacoriCoronado National Forest44,594
Upper Rincon RoadlessCoronado National Forest2,991
WhetstoneCoronado National Forest20,728
WinchesterCoronado National Forest13,459
New Mexico (1)
AreaForestAcres
Peloncillo (NM)Coronado National Forest43,339
References (11)
  1. Arizona Game and Fish Department (AZGFD). 2025. Data export from Biodiversity Tracking and Conservation System (Biotics 5). Arizona Game and Fish Department, Phoenix, AZ (accessed 19 Dec 2025).
  2. Flora of North America Editorial Committee (FNA). 2002a. Flora of North America north of Mexico. Vol. 26. Magnoliophyta: Liliidae: Liliales and Orchidales. Oxford Univ. Press, New York. xxvi + 723 pp.
  3. Global Biodiversity Information Facility (GBIF). 2026. Global Biodiversity Information Facility (GBIF) data portal. Online. Available: https://www.gbif.org/ (accessed 2026).
  4. Hodgson, W., and R. Puente. 2020. <i>Agave schottii</i>. The IUCN Red List of Threatened Species 2020: e.T115690779A116354453. Online. Available: https://dx.doi.org/10.2305/IUCN.UK.2020-1.RLTS.T115690779A116354453.en (accessed 2026).
  5. iNaturalist. 2026. Online. Available: https://www.inaturalist.org (accessed 2026).
  6. Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
  7. NatureServe. 2026. NatureServe Network Biodiversity Location Data. NatureServe, Arlington, Virginia.
  8. <p>NatureServe's Rapid Analysis of Rarity and Endangerment Conservation Assessment Tool (RARECAT). 2025. Version: 2.1.1 (released April 04, 2025).</p>
  9. Rice, K. C. 2014. Center for Plant Conservation National Collection Plant Profile. <i>Agave schottii</i> var. <i>trealesi. </i>Online. Available: https://saveplants.org/plant-profile/?CPCNum=50 (accessed 2014, 2026).
  10. Southwest Environmental Information Network (SEINet). 2026. Collections Databases. Online. Available: https://swbiodiversity.org/seinet/collections/index.php (accessed 2026).
  11. Wildflower Center. 2026. Native Plant Database. Lady Bird Johnson Wildflower Center. Austin Texas. Online. Available: https://www.wildflower.org/plants/ (accessed 2026).