Origin and Habitat: Yucca carnerosanaSN|32946]] is mostly distributed in Brewster (and Culberson?) counties in the Trans-Pecos (Texas, USA ), and adjacent Mexico (Chihuahua, Coahuila, Zacatecas, San Luis Potosi, Nuevo Le6n, Tamaulipas ). Type locality Limestone Hills, Carneros Pass, Carneros, Northeastern Mexico (Coahuila). It is cultivated in Europe and elsewhere.
Altitude range: 450-2200 metres above sea level.
Habitat and ecology: This species usually grows on limestone soils in association with Yucca torreyiSN|27871]]SN|30022]], Yucca rostrataSN|30022]]SN|27871]] and Yucca carnerosanaSN|32946]]. Although it occasionally occurs in small patches along the lower bajada washes, it is usually thinly scattered on dry rocky slopes in desert scrub or pine-oak forest in the eastern and southeastern foothills of the Carmen Mountains.

• Yucca carnerosana (Trel.) McKelvey
• Samuela carnerosana Trel.

Description: Carneros Yucca (Yucca carnerosanaSN|32946]]SN|32946]]) is is a large shrub or small tree, and one of the tree species of yucca, sometimes reaching 6 metres tall with a massive trunk about 30 cm in diameter, capped with a beautiful symmetrical rosette of leaves up to 2.5 metres in diameter. The trunks of this species are quite robust and they are densely covered with dried old leaves. On a tall specimen the oldest leaves may eventually loosen and fall away to reveal the gray-brown trunk. The leaves of Y. carnerosana are swordlike and to 1 metre long, with curling fibrous threads along their edges and a stout sharp tip. It flowers only once every three to four years, producing flower clusters up to 2.1 m tall and weighing 30 kg. Flower colour is creamy-white.
Stem: (150-) 200 to 350 cm tall (occasionally up to 10 metres tall), and up to 35 cm thick, generally simple or rarely branched once or twice 150 to 200 cm above ground level., sometimes forming groups of stems united at the base.
Rosettes: symmetrical
Leaves: 50 to 100 cm long, 5,2 to 7,5 cm wide, rigid, constricted near the base, smoothly yellow-green to bluish-green, with white, thready filaments along the leaf margins
Inflorescence: 150 to 200 cm tall and mainly unbranched, scape large and strong 75 to 100 cm tall 7,5 to 10 cm thick at the base. Bracts persistent, white. Panicle ellipsoid, starting 30 cm above the leaves and haveing about 20 to 30 branchlets, which are from 15 to 60 cm long.
Flowers: 4,5 to 9,5 cm long, strongly scented. Flower parts united to the extent of 25 mm. Outer tepals 67-94 mm long, 13-21 mm wide. Inner tepals 65-93 mm long, 20-28 mm wide. Tube 17-30 mm long. Anthers 0,5 to 0,7 cm in length, pistil 5,5 to 7 cm long, ovary approximately 5 times as long as broad and 0,7 to 1,2 cm thick. Style 0,7 mm long 3 mm thick.
Fruit: Leathery capsules, fleshy, indehiscent, oblong, 5-10 cm long, 4 cm thick
Seeds: Black, thick, and wingless 7-9 x 8-10 mm.
Blooming Period: Spring (mostly March to April). The dense cluster of flowers shoots up with breathtaking speed so that one might see the beginnings of an emerging stalk one week and then come back to find it already in flower the next.
Additional Comments: It is likely that Y. carnerosana and Yucca faxonianaSN|30019]], Faxon Yucca, will soon be considered one species, but Y. carnerosana is a large imposing plant with thick white filaments, while Yucca faxonianaSN|32946]]SN|30019]], which mainly grows in Texas, has leaves that are a little wider and shorter with almost no filaments and a plume of flowers that does not rise as high above the leaves. Some authorities consider the two to be merely variants of one species, with the name Y. faxoniana taking precedence. In habitat it can be possible to find hybrids of Yucca carnerosanaSN|30019]]SN|32946]] x Yucca faxonianaSN|30019]] or Yucca carnerosanaSN|32946]]SN|32946]] x Yucca decipiens.

Bibliography: Major references and further lectures
1) McKelvey "Yuccas of the S.W. U.S". 1:24 1938
2) Aggie horticulture, Texas A&M University, “Carneros Yucca, Giant Yucca, Giant Dagger, Palma, Palmilla, Spanish Dagger, Palma Barreta, Palma Samandoca Yucca carnerosana” Retrieved 04 May 2016 from <http://aggie-horticulture.tamu.edu/ornamentals/natives/YUCCACARNEROSANA.HTM>
3) Brian Kemble “Make a statement with Yucca carnerosana” Posted: 04/13/2016 10:00:00 AM PDT in the Mercury news, Lifestyles, retrieved 04 May 2016 from <http://www.mercurynews.com/ci_29787577/museum-broken-relationships-will-put-heartbreak-display-l?source=infinite-up>
4) Benny Møller Jensen “Yucca carnerosana” Retrieved 04 May 2016 from Benny Cactus, <http://www.bennyskaktus.dk/Y_carne.htm>
5) Benny J. Simpson “A Field Guide to Texas Trees” Taylor Trade Publishing, 01 February 1999
6) Fritz Hochstätter “Yucca (Agavaceae). volume II , Indehiscent-fruited species in the Southwest, Midwest and East of the USA,” Selbst Verlag. 2002
7) Fritz Hochstätter “Yucca (Agavaceae). Volume III Mexico”, Selbst Verlag, 2004
8) Mcelvey “ Yuccas of the S.W.U.S.” 1: 24-28, 1938.
9) Thiede, J., “Illustrated handbook of succulent plants vol. 1. (Monocotyledons (Eggli ed.)”: 91, 2002. (Yucca carnerosana).
10) Webber, “Agric. Monograph” U.S.D.A. 17: 18, 1953.
11) A. Michael Powell “Trees & Shrubs of the Trans-Pecos and Adjacent Areas” University of Texas Press, 05 July 2010
12) George A. Petrides “A Field Guide to Western Trees: Western United States and Canada” Houghton Mifflin Harcourt, 1998
13) United States. Forest Service, International Union of Forestry Research Organizations “Arid land resource inventories: developing cost-efficient methods” U.S. Dept. of Agriculture, Forest Service, 1981
14) R. K. Maiti “World Fiber Crops” Science Publishers, 01 January 1997

Cultivation and Propagation: Yucca carnerosanaSN|32946]]SN|32946]] is a slow growing, carefree and durable plant admired for its spherical form and fine texture and has become one of the most sought after of the woody lilies. It is among the yucca species that form a trunk with age and won't be passed over by anyone with an appreciation for sculptural plants. Plants of Y. carnerosana are cold tolerant and easy to grow, although good drainage is always recommended. The symmetry of the heads of stiff leaves, together with the stout erect trunks, give the plants a formal look.
Soil: Plant in very fast draining soil. It is adapted to a hot, dry environment, but has some tolerance to moisture and humidity when planted in a very well-draining soil. It is noted as preferring alkaline conditions.
Waterings: Provide little or no water in winter. Treat like a succulent. However, they grow faster if watered well (don't water the crown, though they rot easily). In the garden they should be placed in a sunny, well-drained area with additional summer water in dry climates.
Exposure: They thrive best in full sun, but can be grown with some shade and humidity, but may become leggy.
Uses: These make great specimen plants for xeriscape gardens and blend well in either tropical or arid gardens. Small plants are relatively inexpensive, but larger ones are a fortune. These make excellent potted specimens, and their symmetrical form provides a striking focal point, ans display wonderful shadows when illuminated by night lighting. In cooler climates they thrive well in gravel garden, as they have proven quite hardy because of the excellent drainage.
Other uses: The “ixtle fibers” from the leaves of Yucca carnerosanaSN|32946]]SN|32946]], are strong and of high quality. The fibre is used largely in dish washing and house construction. The leaf fibers of Yucca elata and Yucca carnerosanaSN|32946]]SN|32946]] are used in the manufacture of insoles and sandals.
Hardiness. Best where winter temperatures stay above 0° C, but is hardy to around -12° C. Plants in containers can be moved inside during longer cold spells. USDA Hardiness Zone: 5.
Maintenance: When the trunk is pruned of the older, lower leaves, the remaining leaf bases create a beautiful symmetrical spiral leaf-base pattern.
Propagation: Easy to propagate from seeds or cuttings (If available).