View source for Stenocereus thurberi

{{SPlantbox
|familia=Cactaceae
|genus=Stenocereus
|species=thurberi
|common_name=Organ pipe cactus
|name_ref=Flora - A Gardener's Encyclopedia
|habit=cacti-succulent
|habit_ref=Flora - A Gardener's Encyclopedia
|Min ht box=3
|Min ht metric=ft
|Max ht box=25
|Max ht metric=ft
|height_ref=Flora - A Gardener's Encyclopedia
|Min wd box=3
|Min wd metric=ft
|Max wd box=15
|Max wd metric=ft
|width_ref=Flora - A Gardener's Encyclopedia
|lifespan=perennial
|life_ref=Flora - A Gardener's Encyclopedia
|exposure=sun
|sun_ref=Flora - A Gardener's Encyclopedia
|features=flowers
|flowers=white
|Temp Metric=°F
|min_zone=9
|usda_ref=Flora - A Gardener's Encyclopedia
|max_zone=10
|image=Organ pipe cactus.jpg
|image_width=200
|image_caption=Organ Pipe Cactus
}}
The '''Organ Pipe Cactus''' (''Stenocereus thurberi'') is a species of [[cactus]] native to [[Mexico]] and the [[United States]]. The species is found in rocky desert. Two subspecies are recognized based on their distribution and height. The [[Organ Pipe Cactus National Monument]] is named for the species. 

It is locally known as '''''pitahaya dulce''''', [[Spanish (language)|Spanish]] for "sweet [[pitahaya]]". Elsewhere, this refers to ''[[Hylocereus]]'' fruit, which do not grow well in the Organ Pipe Cactus' [[arid]] range.

This cactus species has several narrow stems that rise vertically, growing from a single short trunk just above the ground level. These stems are about 6 inches (15&nbsp;cm) thick and grow to a height of 16 feet (5&nbsp;m), however it has been known to reach 23 to 26 feet (7 to 8&nbsp;m).<ref name=des>{{cite book | author = Johnson, G. Mark | date = 2003-03-26 | title = The Ultimate Desert Handbook | publisher = McGraw-Hill Professional | isbn = 0-07-139303-X | page = 27}}</ref>  These stems rarely branch but rather grow annually from the tip of the last growth. The mature plant can reach a width of 12 feet (3.7&nbsp;m). Each stem has 12 to 19 1/3 inch (.85&nbsp;cm) high ribs that bear dark brown to black spines that turn gray as it matures. It takes 150 years to reach maturity.<ref name=des/> The older plants produce three-inch (8&nbsp;cm) funnel-shaped white flowers annually which are open at night and close by the morning and have a purple or pink tint to them. These usually grow during April, May, and June. The organ pipe cactus is usually pollinated by bats. The plant also produces fruit about the size of a tennis ball. Beneath the fruit's spined exterior is red flesh that supposedly tastes like watermelon.<ref name=sw>Native Plants for Southwestern Landscapes, University of Texas Press, ISBN 0-292-75147-8</ref> This fruit has traditionally been harvested by the [[Seri]]s, who call the plant '''ool''' {{IPA-all|oːɬ|}}, and is used as a medicine.<ref name=cact>Cactus Family, Timber Press, ISBN 0-88192-498-9</ref><ref name=ethnseri>People of the desert and sea: ethnobotany of the Seri Indians, Tucson: University of Arizona Press, ISBN 0-8165-0818-6</ref>

This species is found mostly in [[Mexico]], mainly in [[Sonora]] and southern [[Baja California Sur|Baja California]]. It is also known to the United States, but is much rarer, with the notable exception of [[Organ Pipe Cactus National Monument]]. The plant is predominantly found on rocky hillsides up to 3000 feet (900&nbsp;m) in elevation.