_The Red Clover (Fig. 245). (Trifolium pratense._[47])--This beautiful dweller in our fields came to us from Europe, and it is also a native of Asia. It is the clover most widely cultivated in New York State for fodder, and is one of our most important crops. Clover hay often being a standard of excellence by which other hay is measured. The export of clover seed from the United States has sometimes reached the worth of two million dollars per year, and this great industry is supposed to be carried on with the aid of that other partner of the red clover, the bumblebee. Bumblebees had to be imported into Australia before clover seed could be produced there. The whole question of the relation of the bumblebee to the pollination of clover no doubt needs to be re-studied, for recent observations have led to the contesting of prevailing opinions. It has been supposed that the failure of the clover seed crop in some places is due to the destruction of bumblebees; whether this is true or not, we are certain that bumblebees visit clover blooms, and the teacher can observe for himself. [47] Pronounced _Trifol' -ium praten' -se_, the second or specific name with three syllables. There is a more perennial form of red clover, known as variety _perenne_. It is distinguished from the common form of red clover by its taller growth and mostly less hairy herbage, and by the fact that the flower-head is usually somewhat stalked. Some persons regard it as a hybrid of red and zig-zag clover. _Zig-Zag Clover. (T. medium.)_--This is another species of red clover, resembling the one just discussed, except that its flower-head rises on a long stalk above the upper leaves, while the red clover has the flower-head set close to these leaves. The color of the blossom is darker than in red clover, and the flower-head is looser. The stems of the zig-zag clover are likely to be bent at angles and thus it gets its name. It is a question whether this species is really grown on farms. It is probable that some or all of the clover that passes under this name is _Trifolium pratense_ var. _perenne_. At all events, the zig-zag clover seems to be imperfectly understood by botanists and others. _Crimson Clover--Scarlet Clover (Fig. 246). (T. incarnatum.)_--While this beautiful clover grows as a weed in the southern parts of our State, it has only recently begun to play an important part in our horticulture. It is an annual, and its home is the Mediterranean region of Europe. It thrives best in loose, sandy soils, and in our State is chiefly used as a cover-crop for orchards, and to plow under as a fertilizer. It usually has bright, crimson flowers, arranged in a long, pointed head, and its brilliant green fan-shaped leaves make it the most artistically decorative of all our clovers. [Illustration: _Fig. 246. Crimson clover._]