ABSTRACT
Cannabis sativa, best known as the source of marijuana, is the world’s most recognizable, notorious, and controversial plant. As befits a species that has captured the world’s attention, it is impressive in appearance (Figure 1.1). While the structure of plants may seem much simpler than that of animals, the architectural adaptations of C. sativa are very complex and are cleverly designed to carry out a wide variety of functions (Chapter 6). Cannabis plants vary enormously in height depending on environment and whether selected for stem fiber (the tallest kind), but are typically 1-5 m tall. Simmonds (1976) stated that hemp has been known to grow to 12 m in height, but it should be kept in mind that, as discussed later, other plants called “hemp” sometimes grow to such heights and are often confused with C. sativa. The main stalk is erect, furrowed (especially when large), with a somewhat woody interior, and it may be hollow in the internodes (portions of the stem between the bases of the leaf stalks). Although the stem is more or less woody, the species is frequently referred to as an herb or forb (an herbaceous flowering plant that is not grass-like, i.e., not like grasses, sedges, or rushes). Both herbs and forbs are defined as lacking significant woody tissues, so these terms are not really accurate. As discussed in this book, in many respects, deciding on appropriate terminology for cannabis is contentious.
