CANNABIS SATIVA 2.15 



Orient. In the Western Hemisphere, especially in Mexico and 

 southwestern United States, the drug is known as "marihuana" and 

 is smoked in cigarettes. In many places, the species has become a 

 most troublesome weed. 



Hemp is grown for fiber in Russia and throughout Europe, 

 especially in Italy, as well as in Africa, India, China, Japan, and 

 to a lesser degree in Brazil and the United States. Russia produces 

 more hemp for export purposes than all other countries, but the 

 fiber of best quality is produced in Italy, owing in part to the 

 manner in which the fiber is retted. The production in this coun- 

 try is confined chiefly to Wisconsin and Kentucky, and much of 

 the seed used elsewhere is raised in the latter state. Hemp is also 

 grown in Nebraska, California, Indiana, and New York. 



GENERAL MORPHOLOGY 



The plant is an annual and at maturity develops a rigid, woody 

 stem ranging in height from 3 to 16 feet. The tallest forms are 

 produced in China and Japan, where the slender, sparsely branched 

 stalks have internodes 8 to 10 inches long. The European varieties 

 are usually shorter with more rigid stems, and require 10 to 15 days 

 less time to mature than do the Asiatic forms. 



The Shoot. — The young stem is succulent, but it lignifies 

 rapidly. At maturity, it is obtusely hexagonal, more or less 

 grooved or furrowed; and the most common varieties in this 

 country have a hollow stem. As Heuser (15) has pointed out, cul- 

 tural conditions exert a great influence on the form of the plant, 

 especially with respect to length of stem and degree of branching. 

 Where the crop is not crowded, a single plant may occupy a large 

 area, becoming much branched and attaining a bushy habit, and 

 cases have been reported in which the main axis attained a diameter 

 of 6 cm. or more. Such plants are undesirable for commercial fiber, 

 and the best results are obtained when the crop is seeded thickly 

 so that they are slender and essentially unbranched except at the 

 tip. Under these conditions, the diameter of the stem may range 

 from 6 to lo mm. It is not uncommon for the lower portion of the 

 stem to exhibit a definite curvature known as "wind-bending," 

 which results from the pressure of prevailing winds on young 

 plants. This and other mechanical stresses may have a detrimental 

 effect upon the quality of the fiber produced. 



The stem is leafy, but the leaves fall from the lower portions of 



