Kudzu protection with special reference to influence of frequency of cutting on yields and formation of root rserves

Experiments with kudzu regarding the effect of number of cutting treatments on yields and on the production of reserve foods in the roots brought out the following facts: 1. The fewer the number of cuttings the greater is the production of root reserves. The roots of plants receiving six cuttings per season decreased in weight during a period of two years, those from plants receiving four cuttings increased about 150%, those from plants receiving two cuttings increased approximately 400%, and those from plants receiving one cutting increased about 1,250%. 2. Yields of top were found to be dependent on the amount of reserve food stored in the roots. The greater the amount of root storage, the greater is the yield of top. 3. The greatest yield of tops was secured with the two-cutting treatment when the roots were of equal size at the beginning of the experiment. Due to the greater amount of storage material formed in the roots during the first year from plants cut only once, however, the greatest yield secured the second year was from the one-cutting treatment. 4. The percentage of reserve starch and nitrogen was found to be less than one-half as much in the roots from plants receiving six cuttings as in the roots of plants receiving four or a less number of cuttings. The percentage of total sugars, however, was found to be greater. This is taken to indicate that a change from starch to sugar is taking place in the roots of plants receiving six cuttings in order to produce new top growth. A study of the changes during the season in the reserve food storage of the roots of plants receiving no cuttings and the effect of late cutting on these reserves gave the following results: 1. The percentage of sugar did not change materially during the season. 2. The percentage of nitrogen was high at the beginning of the season and gradually decreased, while growth was rapid until sometime in August. Then, it again increased until the end of the season. 3. The percentage of starch and dextrins remained very constant until sometime in September and then increased very markedly from about 30 to 45%, calculated as dextrose. 4. Cutting the tops as late as September 5 caused a marked reduction in the percentage of starch and dextrins and an increase in the percentage of sugars and water found in the roots for the remainder of the season. Studies made in order to determine the effects of planting various sized roots on the vigor of the plants showed that the top growth from large roots was much more rapid than from small roots. This was taken as additional evidence that top growth is dependent to a large extent on the reserve storage materials in the roots. The practical field applications of these results are discussed.