: Cylindropuntia leptocaulisSN|10935]]SN|10935]] is widely distributed, occurring in the Mexican states of Aguascalientes, Chihuahua, Coahuila, Durango, México State, Guanajuato, Hidalgo, Jalisco, Nuevo León, Puebla, Querétaro, San Luis Potosí, Sonora, Tamaulipas, Veracruz, and Zacatecas. It is widely distributed in the Chihuahuan Desert Region . In the United States it occurs in Arizona, Colorado, New Mexico, and Texas. The population in the Tehuacán-Cuicatlán region in Puebla is disjunct from the main population. Records from Baja California Sur require confirmation. This is the most wide-ranging cholla species.
Altitude range: 40-1500 metres above sea level.
Habitat and Ecology: The species inhabits deserts, grasslands, xerophyllous scrub, oak-juniper woodlands, bajadas and slopes, on sandy, loamy to gravelly substrates. It can survive in human modified habitats. In Tiburon island it grows near the shore, where it generally occurs with Peniocereus striatusSN|7900]]SN|7900]]. The reproductive potential of this species is enormous, being able to reproduce sexually and also asexually by detachable stem fragments. There are no major threats for this species. Stem fragments are easily dispersed by cattle. Its range and population are likely increasing with cattle-ranching.

• Cylindropuntia leptocaulis (DC.) F.M.Knuth in Backeb. & F.M.Knuth
• Grusonia leptocaulis (DC.) G.D.Rowley
• Opuntia leptocaulis DC.

• Cylindropuntia leptocaulis (DC.) F.M.Knuth in Backeb. & F.M.Knuth
• Grusonia leptocaulis (DC.) G.D.Rowley
• Opuntia leptocaulis DC.
• Cylindropuntia brittonii (J.G.Ortega) Backeb.
• Opuntia brittonii J.G.Ortega
• Opuntia leptocaulis var. brittonii (J.G.Ortega) Bravo
• Cylindropuntia leptocaulis var. badia (A.Berger) F.M.Knuth
• Opuntia leptocaulis var. badia A.Berger
• Cylindropuntia leptocaulis var. brevispina (Engelm.) F.M.Knuth
• Opuntia frutescens var. brevispina Engelm.
• Opuntia leptocaulis var. brevispina (Engelm.) S.Watson
• Opuntia leptocaulis f. brevispina (Engelm.) Schelle
• Cylindropuntia leptocaulis var. glauca Backeb.
• Cylindropuntia leptocaulis var. longispina (Engelm.) F.M.Knuth in Backeb. & F.M.Knuth
• Opuntia frutescens var. longispina Engelm.
• Opuntia leptocaulis var. longispina (Engelm.) A.Berger
• Opuntia leptocaulis f. longispina (Engelm.) Schelle
• Opuntia leptocaulis var. stipata J.M.Coult.
• Cylindropuntia leptocaulis var. pluriseta (A.Berger) F.M.Knuth
• Opuntia leptocaulis var. pluriseta A.Berger
• Cylindropuntia leptocaulis var. robustior (A.Berger) F.M.Knuth
• Opuntia leptocaulis var. robustior A.Berger
• Cylindropuntia leptocaulis var. vaginata (Engelm.) F.M.Knuth
• Opuntia frutescens Engelm.
• Opuntia leptocaulis var. vaginata (Engelm.) S.Watson
• Opuntia leptocaulis f. vaginata (Engelm.) Schelle
• Opuntia vaginata Engelm. in Wisliz.
• Cylindropuntia mortolensis (Britton & Rose) F.M.Knuth in Backeb. & F.M.Knuth
• Opuntia mortolensis Britton & Rose

: CylindrSN'>16241' alt='10936'>Opuntia whipplei#SN#16242'>Cylindr[[Opuntia whippleiSN' style='border:none;'>SN|10935]] (syn. Opuntia leptocaulisSN|10936]]SN|10936]]) (desert Christmas cactus, pencil cactus) is a slender spiny or nearly spineless cactus, usually bushy, variously branched, often compact, 0.2 to 2 metres high, but sometimes treelike with a short, definite trunk. As its common names indicate, it has pencil-sized and -shaped stems, which are green and hold on to showy, bright red or red-orange fruits well into winter. Many plants have proliferating chains of 2 or 3 fruits. In most cases, the stems are slightly thinner than a pencil and are decorated with a dark purplish band running lengthwise. The pale yellowish or cream flowers are less than 2 cm in diameter and open in late afternoon. The silver spines are about 2.5 cm long and grow at almost a right angle to the stem, but pointing slightly downward. Young plants produce a moderately thickened tuberous root.
Stem: Main stem (trunk) 5 to 8 cm in diameter, dull green with darker blotches below the areoles, with very slender, cylindric, ascending, hardly tuberculate branches, grey-green to purplish, 20-80 cm long, especially the fruiting ones, thickly set with short, usually spineless joints spreading nearly at right angles to the main branches, easily detached. Stem segments usually alternate, grey-green or purplish, 20-80 mm long, 3-5(-6.5) mm in diameter. Tubercles linear, drying as elongate, riblike wrinkles, 11-20(-30) mm long.
Areoles: With very short white to yellow wool, becoming grey with age, broadly elliptical. Glochids yellow to reddish brown, 1-5 mm long.
Leaves: Green, awl-shaped, 12 mm long or less, acute.
Spines: Usually solitary concentrated on apical areoles of the main branches, evenly distributed on segments, at areoles of old branches 2 or 3 together, very slender, round in cross section, angular-flattened basally, erect, flexible, straight or curved, 2 to 5 cm long or less, reddish brown with with white or grey coats. Sheaths of spines closely fitting or loose and papery, gray to purple-gray with yellow to red-brown tips or yellow throughout.
Flowers: 1-5 to 2 cm. long including the ovary. Inner perianth segments, greenish or yellowish, sometimes with reddish tips, narrowly obovate, 5-8 mm, acute, apiculate. Outer perianth segments broadly ovate, acute, or cuspidate. Ovary obconic, bearing numerous small woolly brown areoles subtended by small leaves, its glochids brown. Filaments greenish yellow; anthers yellow. Style yellow; stigma lobes greenish yellow.
*Fruits: Numerous, small, globular to obovate or even clavate, often proliferous, green, often with purple tint, becoming red or rarely yellow at maturity, 9-18(-27) mm long, 6-7(-12) mm in diameter turgid, slightly fleshy, smooth and spineless. Umbilicus 2-4 mm deep. Areoles 16-20.
Blooming season: Spring-early summer, sometimes autumn (Mar-Aug, Oct).
Seeds: Compressed, suborbicular to squarish and crenate in outline, warped, 3 to 4 mm broad, with narrow, often acute, margins.
Chromosome number: 2n = 22, 33, 44. It seems that O. leptocaulis is tetraploid in the Chihuahuan Desert Region and diploid, or tetraploid in the Sonoran Desert region. The general absence of fertile, intermediates (triploid 2n = 33), there would be ample justification for interpreting them as distinct species. CylindrSN'>10803' alt='7631'>Opuntia versicolor#SN#10805'>Cylindr[[Opuntia versicolorSN' style='border:none;'>SN|10935]] forms hybrids with CylindrSN'>16250' alt='16289'>Opuntia spinosior#SN#16252'>Cylindr[[Opuntia spinosiorSN' style='border:none;'>SN|7630]] var. major (see Cylindropuntia x tetracantha), CylindrSN'>11023' alt='11024'>Opuntia fulgida#SN#11024'>Cylindr[[Opuntia fulgidaSN' style='border:none;'>SN|10916]], Cylindropuntia arbusculaSN|11023]], CylindrSN'>16288' alt='16252'>Opuntia kleiniae#SN#16289'>Cylindr[[Opuntia kleiniaeSN' style='border:none;'>, CylindrSN'>7630' alt='10805'>Opuntia acanthocarpa#SN#7631'>Cylindr[[Opuntia acanthocarpaSN' style='border:none;'>SN|16250]], CylindrSN'>10935' alt='10936'>Opuntia leptocaulis#SN#10936'>Cylindr[[Opuntia leptocaulisSN' style='border:none;'>SN|10803]], and CylindrSN'>10935' alt='16242'>Opuntia leptocaulis#SN#10936'>Cylindr[[Opuntia leptocaulisSN' style='border:none;'>SN|16241]]. The chromosome number reported for hybrids is 2n = 22.

: Major references and further lectures
1) Edward Anderson “The Cactus family” Timber Press, Incorporated, 2001
2) Nathaniel Lord Britton, Joseph Nelson Rose “Cactaceae: Descriptions and Illustrations of Plants of the Cactus Family” vol. 1 The Carnegie Institution of Washington, Washington 1919
2) James Cullen, Sabina G. Knees, H. Suzanne Cubey "The European Garden Flora Flowering Plants: A Manual for the Identification of Plants Cultivated in Europe, Both Out-of-Doors and Under Glass" Cambridge University Press, 11/Aug/2011
3) David R Hunt; Nigel P Taylor; Graham Charles; International Cactaceae Systematics Group. "The New Cactus Lexicon" dh books, 2006
4) Leo J. Chance “Cacti and Succulents for Cold Climates: 274 Outstanding Species for Challenging Conditions” Timber Press, 19 June 2012
4) Goettsch, B. and Hernández, H.M. "Beta diversity and similarity among cactus assemblages in the Chihuahuan Desert." Journal of Arid Environments Latinoamericana y del Caribe de Cactáceas y otras Suculentas 65: 513-528. 2006.
5) Hernández, H.M., Gómez-Hinostrosa, C. and Goettsch, B. “Checklist of Chihuahuan Desert Cactaceae.” Harvard Papers in Botany 9(1): 51-68. 2004.
6) Martínez-Ávalos, J.G. and Jurado, E.“Geographic distribution and conservation of Cactaceae from Tamaulipas Mexico”. Biodiversity and Conservation 14: 2483-2506. 2005.
7) Hernández, H.M., Cházaro, M. & Gómez-Hinostrosa, C. 2013. Cylindropuntia leptocaulis. The IUCN Red List of Threatened Species 2013: e.T152600A655822. http://dx.doi.org/10.2305/IUCN.UK.2013-1.RLTS.T152600A655822.en. Downloaded on 17 March 2016.
8) Augustin-Pyrame de Candolle “Revue de la Famille des Cactées”. In: Memoires du Museum d'Histoire Naturelle, 17: 118 1828, retrieved 18 Mach 2016 from: <http://biodiversitylibrary.org/page/26229185#page/128/mode/1up>
9) A. Michael Powell, James F. Weedin “Cacti of the Trans-Pecos & Adjacent Areas” Texas Tech University Press, 2004
10) “Cylindropuntia leptocauli” in Flora of North America @ efloras.org FNA Vol. 4 Page 101, 104, 105 . retrieved 17 March 2016 from <http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=242415140>
11) Richard S Felger, Benjamin Theodore Wilder, Humberto Romero-Morales “Plant Life of a Desert Archipelago: Flora of the Sonoran Islands in the Gulf of California” University of Arizona Press, 31 january 2013

: Cylindropuntia molestaSN|16362]]SN|16362]] is a a much decorative hardy cactus occasionally grown for horticultural purposes. It is a summer grower species that offers no cultivation difficulties. Throughout its natural range it is often used in gardens and is a carefree, attractive plant. The stems get thinner in winter but do not droop, making this cholla a good year-round garden subject. Its cylindrical densely spiny joints provide a striking accent for an otherwise dormant cactus garden. The species is incredibly widespread in nature, with some clones much more tolerant of cold and winter moisture than others.This small to medium-sized cholla seldom 1.2 m)tall in cold climates, although it becomes a densely branched bush.
Soil: Use a very a particularly draining substratum, as it is sensitive to rottenness when in presence of humidity and low temperatures and let the soil dry out between waterings, since it's natural habitat is in sandy or gravelly, well draining soils.
Repotting: Repot in the spring, when their roots become cramped. Generally, they should be repotted every other year in order to provide fresh soil. After repotting, do not water for a week or more.
Water: In summer, during the vegetative period, it must be regularly watered, but allowing the substratum to completely dry up before irrigating again (but do not overwater); in winter, it’s to be kept dry. Preferable not to water on overcast days, humid days or cold winter days.
Hardiness: It is a not very frost resistant cactus, hardy to -2° C (or less if very dry). However in cultivation it is better not to expose it to temperatures lower than -0° C, even if in an aerated and protected location, in order to avoid the formation of anti-aesthetic spots on the epidermis. In presence of high atmospheric humidity avoid any frost as it is particularly sensitive to root rot. It can handle extremely high temperatures in summer.
Exposure: Outside full sun or afternoon shade, inside needs bright light, and some direct sun.
Use: It is suitable for “desert” gardens, in association with other xerophytes. Where the open air cultivation is not possible due to the climate, it is to be cultivated in pot in order to shelter it in winter.
Traditional uses: The small, red fruit are known among the Spanish-Americans as tasajulla and garrambulo.
Warning: It is armed with treacherous spines that are extremely sharp (This is one of the most dangerous of all cactus). Handle it with extreme caution, and keep it away from gangways and areas frequented by children and animals. Spines must be meticulously removed with tweezers.
Propagation: Scarified seeds, stem division. The stem segments root easily and grow rapidly when placed in loose, well-draining soil.