speaking of crested: Myrtillocactus geometrizans (bilberry cactus, whortleberry cactus or blue candle) is a species of cactus in the genus Myrtillocactus, native to central and northern Mexico.

Cultivation
It is a popular species in cultivation, where young plants commonly remain unbranched for many years. The fruit is edible, and sold for consumption in Mexico.

The bilberry cactus is fast growing, and is often used as grafting stock because of this. With favourable conditions it can reach heights of up to 15 feet.