Cactus, Peebles Navajo

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Cactus, Peebles Navajo

Pediocatus peeblesianus

division: Magnoliophyta

class: Magnoliopsida

order: Caryophyllales

family: Cactaceae

status: Endangered, ESA

range: USA (Arizona)

Description and biology

The Peebles Navajo cactus is a small, globe-shaped cactus with no central spine. Like other cacti, it is a succulent (plant that has thick, fleshy, water-storing leaves or stems). It grows to a height of 2.4 inches (6.1 centimeters) and to a width of 2 inches (5.1 centimeters).

This cactus species blooms in the spring. Its yellow to yellow-green flowers measure up to 1 inch (2.5 centimeters) in diameter. The plant also bears berrylike fruit that turn from green to tan or brown when they ripen.

Habitat and current distribution

The Peebles Navajo cactus is found on low hills in Navajo County, Arizona. There are five known populations totaling around 1,000 individual plants. Two populations exist near Joseph City and the other three near Holbrook. The cacti usually inhabit dry gravel soils at elevations around 5,600 feet (1,707 meters).

History and conservation measures

Excessive collecting and habitat destruction are the main reasons for the decline of this cactus species. Because it is so rare and is difficult to grow outside of its natural habitat, the Peebles Navajo cactus is sought after by private collectors and commercial plant suppliers. Areas where it grows are easy to reach, and overcollection could quickly wipe out this cactus.

Road construction, grazing animals, mining activities, and four-wheel-drive recreational vehicles have all destroyed part of the plant's habitat. Since the cactus can grow only in a specific type of soil, its habitat range is limited. Any destruction of that habitat will seriously affect the survival of the cactus.

Conservation efforts have been directed at protecting the Peebles Navajo cactus from collectors and preserving its fragile natural habitat.


While most species of plants are pollinated by birds and insects, members of the Cactaceae family are pollinated predominantly by bats. One of the reasons is that bats are more prevalent than pollinating birds and insects in areas inhabited by cacti. Another reason is that most cacti open their flowers at dusk and hold them open during the night, a time when bats are most active. The pollen produced by cactus flowers is also higher in protein than those of plants pollinated by birds or insects. In this way, the cactus supplies the nutritional needs of the bats, insuring that they will return to help pollinate the plant in the future.