Ferocactus is a genus of large barrel-shaped

Barrel cactus

Barrel cacti are classified into the two genera Echinocactus and Ferocactus, both of which are found in the Southwest Desert of North America. Their pineapple-shaped fruits can be easily removed but are not recommended for eating. The barrel cactus may reach over a metre in height. Its ribs are...

 cacti

Cactus

A cactus is a member of the plant family Cactaceae. Their distinctive appearance is a result of adaptations to conserve water in dry and/or hot environments. In most species, the stem has evolved to become photosynthetic and succulent, while the leaves have evolved into spines...

, mostly with large spines and small flowers. There are about 30 species included in the genus. They are found in the southwestern United States

Southwestern United States

The Southwestern United States is a region defined in different ways by different sources. Broad definitions include nearly a quarter of the United States, including Arizona, California, Colorado, Nevada, New Mexico, Oklahoma, Texas and Utah...

 and northwestern Mexico

Mexico

The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

. The young specimens are columnar but as they grow older ribs form and they take on a barrel form. Most of the species are solitary but some, such as Ferocactus robustus

Ferocactus robustus

Ferocactus robustus is a barrel cactus in the genus Ferocactus belonging to the family Cacteae.-Description:Ferocactus robustus forms large cushions reaching a height up to and a diameter up to . This plant is spherical to club-shaped and has eight sharp-edged ribs. The funnel-shaped flowers are...

and F. glaucescens

Ferocactus glaucescens

Ferocactus glaucescens is a barrel cactus in the genus Ferocactus. F. glaucescens is found in the limestone hills of the state of Hidalgo, Mexico...

, form clumps. The flowers are pink, yellow, red or purple depending on the species, and the petals sometimes have a stripe of a darker colour. They are desert

Desert

A desert is a landscape or region that receives an extremely low amount of precipitation, less than enough to support growth of most plants. Most deserts have an average annual precipitation of less than...

 dwellers and can cope with some frost and intense heat. In cultivation they require full sun, little water, and good drainage. The propagation is usually from seeds.

Like Sclerocactus

Sclerocactus

Sclerocactus is a genus of cacti. It comprises about 15 species, the exact number depending on the authority. These species are very xerophytic...

, Ferocactus typically grow in areas where water flows irregularly or depressions where water can accumulate for short periods of time. They are most often found growing along arroyos

Arroyo (creek)

An arroyo , a Spanish word translated as brook, and also called a wash is usually a dry creek or stream bed—gulch that temporarily or seasonally fills and flows after sufficient rain. Wadi is a similar term in Africa. In Spain, a rambla has a similar meaning to arroyo.-Types and processes:Arroyos...

 (washes) where their seeds have been subjected to scarfication

Scarification (botany)

Scarification in botany involves cutting the seed coat using abrasion, thermal stress, or chemicals to encourage germination.-In botany:Scarification is a natural process important for germination of many species' seeds. This process involves the breaching of the natural seed coating by mechanical,...

 due to water movement, but they oddly also tend to grow along ridges in spots where depressions have formed and can hold water for some period of time.

The "fishhook" spines and the armored web of spines enclosing the cactus body in many species of this genus is an adaptation which allows the plant to move to more favorable locations. This plants seeds germinate in areas where water movement occurs or in areas where standing water accumulates for some period of time, and during flash flood

Flash flood

A flash flood is a rapid flooding of geomorphic low-lying areas—washes, rivers, dry lakes and basins. It may be caused by heavy rain associated with a storm, hurricane, or tropical storm or meltwater from ice or snow flowing over ice sheets or snowfields...

s, the hooked spines allow the plants to be caught on water bourne debris and be uprooted and carried to areas where water tends to accumulate. Ferocactus have very shallow root systems and are easily uprooted during flash floods.

The habitat these plants exist in is hot and very arid, and the plants have adapted to exploit water movement to concentrate their biomass in areas where water is likely to be present.

Ferocactus are very popular as houseplants and are common in cultivation. However, Ferocactus cannot take freezing temperatures for long periods and plants which have been subjected to freezing temperatures for extended periods will typically yellow, bleach, then slowly die.

Many Ferocactus species are ant plants and exude nectar along the upper meristem from extrafloral nectaries above each areole and host and support ant colonies and are subsequently patrolled by ants.

Selected species

• Ferocactus alamosanus
• Ferocactus chrysacanthus
• Ferocactus cylindraceus
  Ferocactus cylindraceus
  Ferocactus cylindraceus is a species of barrel cactus which is known by several common names, including California barrel cactus and miner's compass. It was first described by George Engelmann in 1853. This cactus is usually cylindrical or spherical, with some older specimens forming columns two...
  
  (Engelm.) Orcutt – California Barrel Cactus, Biznaga-barril cilíndrica
  • Ferocactus cylindraceus cylindraceus
  • Ferocactus cylindraceus lecontei (Engelm.) N.P.Taylor
  • Ferocactus cylindraceus tortulispinus (H.E.Gates) N.P.Taylor
• Ferocactus diguetii
• Ferocactus echidne
  Ferocactus echidne
  Ferocactus echidne is a barrel cactus in the genus Ferocactus. It is found in nature in Mexico. This cactus is known commonly as "Sonora Barrel," "Coville's Barrel Cactus," "Emory's Barrel Cactus," and "Traveler's Friend." Alternatively is has been assigned the binomials Echinocactus emoryi,...
  
  – Sonora Barrel Cactus, Coville's Barrel Cactus, Emory's Barrel Cactus, Traveler's Friend
• Ferocactus emoryi (Engelm.) Orcutt – Emory's Barrel Cactus, Biznaga-barril de Emory
  • Ferocactus emoryi emoryi
  • Ferocactus emoryi rectispinus (Engelm.) N.P.Taylor
• Ferocactus flavovirens
• Ferocactus fordii
• Ferocactus glaucescens
  Ferocactus glaucescens
  Ferocactus glaucescens is a barrel cactus in the genus Ferocactus. F. glaucescens is found in the limestone hills of the state of Hidalgo, Mexico...
  
  
• Ferocactus gracilis H.E.Gates – Fire Barrel Cactus
  • Ferocactus gracilis coloratus (H.E.Gates) N.P.Taylor
  • Ferocactus gracilis gatesii (G.E.Linds.) N.P.Taylor
  • Ferocactus gracilis gracilis
• Ferocactus haematacanthus (Salm-Dyck) Bravo ex Backeb. & F.M.Knuth
• Ferocactus hamatacanthus (Muehlenpf.) Britton & Rose – Turk's-Head Barrel Cactus, Biznaga-barril Costillona
• Ferocactus herrerae – Twisted Barrel Cactus
• Ferocactus histrix (DC.) G.E.Linds. – Electrode Cactus
• Ferocactus horridus
• Ferocactus johnstonianus Britton & Rose – Johnston's Barrel Cactus
• Ferocactus latispinus
  Ferocactus latispinus
  Ferocactus latispinus is a species of barrel cactus native to Mexico. Originally described as Cactus latispinus in 1824 by English naturalist Adrian Hardy Haworth, it gained its current name in 1922 with the erection of the genus Ferocactus by American botanists Britton and Rose. The species name...
  
  (Haw.) Britton & Rose
• Ferocactus macrodiscus
• Ferocactus peninsulae
  Ferocactus peninsulae
  Ferocactus peninsulae is a barrel cactus in the genus Ferocactus belonging to the family Cacteae.-Description:Ferocactus peninsulae reaches a height of about . This plant is oval to club-shaped and has 12 to 20 showy, deep ribs. The thorns are grayish-red and have a yellowish or whitish tip. The...
  
  (F.A.C.Weber) Britton & Rose
• Ferocactus pilosus – Mexican Lime Cactus, Viznaga de Lima
• Ferocactus pottsi
• Ferocactus reppenhagenii
• Ferocactus robustus
  Ferocactus robustus
  Ferocactus robustus is a barrel cactus in the genus Ferocactus belonging to the family Cacteae.-Description:Ferocactus robustus forms large cushions reaching a height up to and a diameter up to . This plant is spherical to club-shaped and has eight sharp-edged ribs. The funnel-shaped flowers are...
  
  
• Ferocactus santa-maria – Santa-Maria Barrel Cactus
• Ferocactus schwarzii – Schwarz's Barrel Cactus
• Ferocactus stainesii
• Ferocactus townsendianus – Townsend Barrel Cactus
• Ferocactus viridescens
  Ferocactus viridescens
  Ferocactus viridescens is a rare species of barrel cactus known by several common names, including Coast barrel cactus and San Diego barrel cactus. It is native to southern California and northern Baja California...
  
  (Torr. & A.Gray) Britton & Rose – San Diego Barrel Cactus, Biznaga-barril Verdosa
• Ferocactus wislizeni
  Ferocactus wislizeni
  Ferocactus wislizeni, the fishhook barrel cactus, also called Arizona barrel cactus, candy barrel cactus, and Southwestern barrel cactus, is a cylindrical barrel-shaped cactus.-Characteristics:...
  
  (Engelm.) Britton & Rose – Fishhook Barrel Cactus, Candy Barrel Cactus, Biznaga-barril de Nuevo México

Formerly placed here

• Sclerocactus brevihamatus tobuschii
  Sclerocactus brevihamatus
  Sclerocactus brevihamatus is a species of cactus known by the common name shorthook fishhook cactus. It is native to Texas.One subspecies of this cactus is the Tobusch fishhook cactus , a federally listed endangered species. It is often treated as a species in its own right called Ancistrocactus...
  
  (W.T.Marshall) N.P.Taylor (as F. tobuschii (W.T.Marshall) N.P.Taylor)
• Sclerocactus glaucus
  Sclerocactus glaucus
  Sclerocactus glaucus is a rare species of cactus known by the common name Uinta Basin hookless cactus and Colorado hookless cactus. It is endemic to Colorado in the United States, where it is known only from the area between Grand Junction and Montrose...
  
  (K.Schum.) L.D.Benson (as F. glaucus (K.Schum.) N.P.Taylor)
• Sclerocactus mesae-verdae (Boissev. & C. Davidson) L.D.Benson (as F. mesae-verdae (Boissev. & C.Davidson) N.P.Taylor)
• Sclerocactus pubispinus (Engelm.) L.D.Benson (as F. pubispinus (Engelm.) N.P.Taylor)