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  Opuntia macrorhiza var. pottsii near Midland, Texas, USA
(syn: Opuntia ballii)

Cultivation and Mail Sale
of Cacti and Succulents.

 Compact and small with tuberous roots.

Collector: David Van Langen,  Locality: Near Midland Texas USA. Notes: Plants from this population have long  tuberous roots and are covered in spines, they are really very nice!! they are very cold hardy and stays fairly small and compact.


Morphology (Identifying Characteristics):
Diminutive shrubby plant up to 12cm tall, forming low prostrate clumps up to 2m in diameter.
Stem: Segments are round to obovate, glaucous blue-green, 5-10cm long, 5-6 cm wide, to 1.2 cm thick. Cladodes elongate conical, to 7.5 mm long. wrinkled under very dry or cold conditions.
Glochids: Yellow or brown, to 3 mm long.
Spines: One to five spines from the upper areoles, 2.5 to 6cm long, grey or brownish, acicular and downwards pointing
Roots: Large tuberous and fleshy.
Flower: Yellow with red bases to reddish, appear on early June , 5-6 cm in diameter and long.
Fruit: Obovoid narrow and smooth, purple or reddish purple at maturity, fleshy, 2.5-4 cm long, 2.5-3cm in diameter flattened and irregular.
Seeds: Tan to grey, 5mm in diameter

Two varieties are recognized:
  • var. macrorhiza has only moderately glaucous stem segments that may reach 10 cm in length and diameter and basically yellow flowers.

  • Var. pottsii (Opuntia balliii) has very glaucous compact stem segments reaching 5-6 cm in length and diameter.  It is easily distinguished from other varieties of O. macrorhiza by its red flowers (as opposed to yellow),  and very slender spines. This variety is thought by some experts to deserve specific (species) status.

Photo gallery: Alphabetical listing of Cactus and Succulent pictures published in this site.

Photo gallery Opuntia




Family: Cactaceae (Cactus Family)
Scientific Name:

Scientific name:  Opuntia macrorhiza var. pottsii (Salm-Dyck) L.D. Benson 1969
Published in: The cacti of Arizona 20, 1969

Origin:  Widespread In Midwest and south-western United States and northern Mexico, ranging from Texas to Arizona and New Mexico. (Colorado, Utah, Wyoming, South Dakota, Nebraska, and Missouri)

Habitat: Grows on loam or rocky, sandy places at an elevation of 800 to 2200 m

Conservation status: Listed in CITES appendix 2.

Common Names include:

Etymology: The genus name "Opuntia" refers to a Greek name used by Pliny for a diverse plant which grew in the region of the town of Opus in Greece. 
The species name "macrorhiza" derives from
 the Greek adjective “macros (μακρος)” meaning “large, long, tall, high, deep, far,”, and the Greek word “rhiza (ριζα)”meaning “root, stem, origin”  ( The specific name implies: " large rooted ").
The variety name "pottsii" has been created in honour of "John Potts" manager of a mine in Ciudad Chihuahua who collected cacti for the the prince Salm-Dyck.


  • O. ballii Rose 1911
    in: Contributions from the U. S. National Herbarium 13 (9): 309, t. 64, 1911
  • O. pottsii Salm-Dyck 1850,
    in: Cacteae in Horto Dyckensi Cultae [ed. 1849] 236, 1849[1850]
  • O. macrorhiza Engelmann 1850,
    in: Boston Journal of Natural History 6: 206, 1850
  • O. mesacantha Raf. var. macrorhiza (Engelm.) J.M.Coult., 1896
  • O. compressa (Salisb.) Macbr. var. macrorhiza (Engelm.) L.D.Benson, 1944
  • O. tortispina Engelm. & Bigelow, 1856
  • O. sphaerocarpa Engelm. & Bigelow 1856
  • O. plumbea Rose 1908
  • O. delicata Rose 1911
  • O. setispina Engelm ex Salm-Dyck. 1850
  • O. tenuispina Engelm. 1857
  • O. filipendula Engelm.1856.
  • O. cymochila Engelm. y Bigelow, 1856
  • O. compressa J.F.Macbr. var. grandiflora (Engelm.) Weniger
  • O. compressa J.F.Macbr. var. stenochila (Engelm.) Weniger
  • O. grandiflora Engelm
  • O. leptocarpa Mackensena
  • O. mackensenii Rose

Cultivation: A quite cold tolerant plant, it can succeed outdoors. Requires a sandy or very well-drained soil . Prefers a neutral to alkaline soil. Plants must be kept rather dry in the winter but they like a reasonable supply of water in the growing season. A position at the base of a south-facing wall or somewhere that can be protected from winter rain is best for this plant. Requires plenty of sun. Plants endure considerable abandon.

Photo of conspecific taxa, varieties, forms and cultivars of
plants belonging to the Opuntia humifusa (compressa) complex
(This Taxon has lots of synonyms ( like many other cacti) whit several controversial varieties and subspecies and comprises a multitude of different forms, but where each form is linked to others by populations of plants with intermediate characteristics):

The plant photos in this page courteously provided by David Van Langen

Home | E-mail | Plant files | Mail Sale Catalogue | Links | Information | Search

All the information and photos in cactus art files are now available also in the new the Enciclopedia of Cacti. We hope you find this new site informative and useful.