Xerophyte

Central Spines

1-4, grey to brownish, 2-3 cm long.

Seeds

2-2.5 mm, black, warty.

Description

Stenocereus pruinosusSN|7945]]SN|7951]] is a large shrubby or tree-like columnar cactus to 4-5(-7) m tall, usually with one or more, definite trunk(s) from which little-branching stems arise from the base for a distinctive V-shape. This plant is certainly native in south-central Mexico, and distinguishable from the related cultivated Stenocereus griseusSN|8205]]SN|7855]] by fewer ribs, larger flowers, and ovoid fruit. The pruinose colour of young branches distinguishes it from the other arborescent species. This cactus is also known as 'pitayo de Octubre' or 'pitayo de mayo' in Mexico, which indicates its ripens mainly around October and May.

Taxonomy

Hunt et al. (2006) consider Stenocereus laevigatusSN|7855]]SN|8205]] (Salm-Dyck) Buxb. as part of S. pruinosus, however, Arreola (2006) reports it as valid species. Natural hybrids may be possible with Stenocereus stellatusSN|7951]]SN|7945]].

Phenology

Flowers open in from late February to May and later in September as around the clock bloomers to exploit both day and night flying pollinators and produces fruits between May and October.

Flowers

Borne on new growth at the stem tips. Funnel-shaped, modestly sized up to 9 cm long, 7 cm wide and packed with yellow stamens. Upper scales and outer perianth-segments 1 cm long or less, rounded at apex. Inner perianth-segments white or pinkish longer and thinner than the outer ones. Ovary with numerous brown-felted areoles.

Ribs

5-6 (rarely to 8 or even 10) very hight, separated by broad intervals and with wavy margins.

Stem

8-10(-12) cm in diameter, grey-green to dark green, the new growth often bearing a distinctive white-glaucous bloom near apex.

Radial Spines

5-8, greyish to brownish, radiating, 1-2 cm long.

Fruits

Ovoid the size of a small apple, 5-8 long, varying from yellow, orange-green to purple, without persistent perianth parts. The outer skin of the fruit is spiny in youth, growing smooth with maturity making them easier to harvest.

Areoles

Up to 3-4 cm apart. Flowering areoles large, brown-felted.