While the first crop in the second year comes from the crown buds, the new branches which produce the second crop of the second year come from the buds formed in the axils of the leaves on the lower portions of the stalks which constitute the first crop, as shown in figure 4. These branches usually commence growth when the plants are about 24 inches high. In fields where the stand is heavy and where the lower portions of the plants are densely shaded, these shoots are soon killed from lack of necessary light. (Figs. 4 and 5.) The branches which are first to appear and which are first to be killed are those closest to the ground. It is therefore very important when cutting this crop to cut the plants high enough from the ground to leave on the stubble a sufficient number of buds and young branches to produce a second crop. [Illustration: Fig. 4.--Sweet-clover plants, showing the direct relation that exists between the thickness of stand, the time of cutting, and the height at which the stubble must be cut if a second crop is to be expected. The plant at the left was cut 10 day later than the plant at the right. Note the height at which it was necessary to cut this plant so that a second crop would develop and also the scars on the stubble where young shoots had started earlier and were killed from lack of sunlight. When the stand is thin the young shoots will survive, as they did on the plant at the right, even though the field is cut at a later date.] Examination of hundreds of acres of sweet clover in different sections of the United States during the summers of 1915 and 1916 showed that the stand on at least 50 per cent of the fields was partly or entirely killed by cutting the first crop the second season too close to the ground. A direct relation exists between the thickness of the stand, the height of the plants, and the height at which the stubble should be cut if a second crop is to be harvested. It is very essential to examine the fields carefully before mowing, so as to determine the height at which the plants should be cut in order to leave at least one healthy bud or young branch on each stub. In fact, the stand should be cut several inches above the young shoots or buds, the stubble may die back from 1 to 3 inches if the plants are cut during damp or rainy weather. [Illustration: Fig. 5.--Stubble of sweet clover collected in fields where 90 per cent of the plants had been killed by cutting too closely to the ground. The heavy stands in these fields were not cut until the plants had made a growth of 36 to 40 inches. Note the scars on the stubble where young shoots started, but died from lack of light.]