Opuntia humifusa Opuntia humifusa Opuntia humifusa, commonly known as the devil's-tongue, eastern prickly pear or Indian fig, is a cactus native to parts of eastern North America. As is the case in other "Opuntia" species, the green stems of this low-growing perennial cactus are flattened, and are formed of segments. Barbed bristles are found around the surfaces of the segments, and longer spines are sometimes present. The flowers are yellow to gold in color, and are found along the margins of mature segments. The flowers are waxy and sometimes have red centers. They measure 4–6 cm across. This cactus blooms in the
Plant functional type key parameters are defined, such as fecundity, competitiveness, resorption (rate at which plant decays and returns nutrients to the soil after death), etc.; the value of each parameter is determined or inferred from observable characteristics such as plant height, leaf area, etc. Climatologists and ecologists struggle to determine which minimal set of plant characteristics best model the actual responses of the biosphere in response to climate changes. Plant functional type Plant functional types (PFTs) is a system used by climatologists to classify plants according to their physical, phylogenetic and phenological characteristics as part of an overall effort to develop a