CPC National Collection Plant Profile
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Agave parviflora
Family: |
Agavaceae |
Common Names: |
Santa Cruz striped agave, small-flower agave |
Author: |
Torr. |
Growth Habit: |
Subshrub, Shrub, Forb/herb |
CPC
Number: |
49 |
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Primary
custodian for this plant in the CPC National Collection of Endangered
Plants is: |
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Kathleen C. Rice contributed to this Plant Profile. |
Agave parviflora
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Most plants in the genus Agave are monocarpic, meaning that they spend a number of years growing to maturity before they flower once, produce seeds, and then die. While growing, they accumulate a large quantity of sugar and starch in the 'heart tissue' of the plant. These carbohydrates supply the energy that fuels the rapid development of the inflorescence, which is often enormous in comparison to the plant that produces it. (Phillips et al. 2000).
Agave parviflora is the smallest species of agave in Arizona. It is composed of a small rosette, 10 to 25 cm high, 15 to 20 cm broad and single or sparsely suckering. Leaves are 6 to 20 cm long and 0.8 to 2 cm wide. They are dark green with a waxy coating and beautiful white markings on both surfaces and leaf margins. These markings result from the impression of developing leaf buds on the center of the rosette. White fibers peel off the outer edges of leaf margins. The inflorescence is between 1-2 m tall, and has cream-colored flowers in clusters of 1-4 on very short branches. Fruits mature into small ovoid capsules 6-10 mm in diameter. This is the smallest species of Agave in Arizona, and highly attractive to collectors. Plants offset freely, flowering between the ages of 10-15 years.
Plants are highly desirable in an indoor or greenhouse collection as they remain small, growing to only about six inches in diameter, and are lovely, symmetrical rosettes of dark green leaves with beautiful white leaf traces. This characteristic has contributed to the decline of this species, as illegal collection of these slow-grown plants in the wild can do extensive damage to a population. They live only 15 years or so, but generally produce offsets freely in cultivation. (Gentry 1982)
Distribution
& Occurrence |
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State Range
Habitat
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Plants occur on rocky slopes of desert grassland and oak woodland at elevations from 1,100 to 2,400 meters (Gentry 1982). |
Distribution
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Agave parviflora ranges from southern Arizona to Sonora, Mexico. |
Number Left
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There are approximately two dozen populations of Agave parviflora documented in southern Arizona, and the range of this species extends south into Mexico (Reichenbacher 1986). |
State/Area
Protection
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State/Area |
Rank |
Status |
Date |
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Arizona |
S3 |
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8/1/2002 |
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Sonora |
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7/8/1992 |
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Conservation,
Ecology & Research |
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Ecological
Relationships
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• Cattle eat inflorescences if accessible.
• The flowers mature in late spring to summer, and are pollinated by bumblebees and carpenter bees. Seeds are released gradually from the drying fruit capsules during the fall and winter. (Schaffer and Schaffer 1977, Gentry 1982) |
Threats
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• Agave parviflora is threatened by loss of habitat due to mining and road construction, habitat degradation due to grazing, and illegal collection. (USFWS 2002)
• There is a well-known local story about a tour bus to Mexico passing through a rather dense patch of Agave parviflora. Visitors on the bus were observed digging plants to take back home. Illegal collection is a threat to this species, especially given its slow growth rate and extremely low population numbers.
• Because Agave species in general form hybrids when cross-pollinated with each other, there is always a danger of 'pollution' of a species' gene pool with those of another species. |
Current Research Summary
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Desert Botanical Garden has propagules from three populations in Santa Cruz County, Arizona. Garden staff have conducted controlled cross-pollinations, keeping each population separate and producing a total of 10,554 seeds. |
Current Management Summary
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The species was listed as a Category 2 taxon under the Endangered Species Act, and has now lost its protection through a 1996 revision amending Category 2 plants to 'species of concern'. |
Research Management Needs
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Determine the effects of fire on this species. Search for new populations (New Mexico) and monitor existing populations (Hodgson and Lamater 1989). |
Ex Situ Needs
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The Desert Botanical Garden plans to continue to cultivate and propagate this species. |
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Books (Single Authors)
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Gentry, H.S. 1982. Agaves of continental North America. Tucson, AZ: Univ. Arizona Press.
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Kartesz, J.T. 1996. Species distribution data at state and province level for vascular plant taxa of the United States, Canada, and Greenland (accepted records), from unpublished data files at the North Carolina Botanical Garden.
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Phillips, S.J.; Comus, P.W. 2000. A Natural History of the Sonoran Desert. Tucson, AZ: Arizona-Sonoran Desert Museum Press.
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Books (Sections)
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Kartesz, J.T. 1999. A synonymized checklist of the vascular flora of the U.S., Canada, and Greenland. In: Kartesz, J.T.; Meacham, C.A., editors. Synthesis of the North American Flora, Version 1.0. North Carolina Botanical Garden. Chapel Hill, NC.
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Electronic Sources
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(2000). Center for Plant Conservation's National Living Collection--Profiles. Desert Botanical Garden. http://www.dbg.org/Collections/cpc.html. Accessed: 2002.
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Arizona Game and Fish Department. (1999). Plant Abstracts. Compiled and edited by the Heritage Data Management System, Arizona Game and Fish Department, Phoenix, AZ. http://www.gf.state.az.us/frames/fishwild/hdms_site/Abstracts/Plants/abstracts%20-%20plants.htm. Accessed: 2002.
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USFWS. (2002). U.S. Plant Profiles. U.S. Fish and Wildlife Service, International Affairs. http://international.fws.gov/animals/plantpro.html. Accessed: 2002.
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Journal Articles
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Franco M.; Irma S. 1995. In situ and ex situ conservation of Mexican Agavaceae and Nolinaceae. Boletin de la Sociedad Botanica de Mexico. 0, 57: 27-36.
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Schaffer, W.M.; Schaffer, M.V. 1977. The reproductive biology of Agavaceae: I. Pollen and nectar production in four Arizona agaves. Southwest Naturalist. 22: 157-168.
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Schaffer, W.M.; Schaffer, M.V. 1979. The Adaptive Significance of Variations in Reproductive Habit in the Agavaceae II: Pollinator Foraging Behavior and Selection for Increased Reproductive Expenditure. Ecology. 60, 5: 1051-1069.
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Reports
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Reichenbacher, F.W. 1986. Status report for Agave parviflora. Albuquerque, New Mexico: Prepared for USFWS.
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This
profile was updated on 3/4/2010 |
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