flora de gran canaria - opuntia maxima plant, introduced and invasive

arid barrel-shaped blue-grey cactaceae cactus camuesa canaria canary difficult dry edges edible eradicate fiber fibrous flattened fleshy flora floral flower fruit gran hard introduced invasive islands lands maxima mixed nopal open opuntia organic pear pink plants prickly purple rocky round segments sessile sharp shrub slopes species spines stem succulent tough unusual wheel woodlands yellow