Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)

Department / School

Animal Science


One of the major factors influencing the nutritional value of grass is stage of maturity. The relationship of lignification to maturity and plant digestibility has been studied extensively. One of the purpose of this study was to determine the effect of stage of maturity on hemicellulose content of western wheatgrass and further the content of its component sugars. Western wheat grass is a rhizomatous cool season perennial grass which is very important in South Dakota ranges. Another purpose of this study is to note whether cutting date and leaf number are good measures of the stage of maturity as measured by their relationship to lignin content and in vitro digestibility. Hemicelluloses are complex polysaccharides closely associated with the cellulose of plant cell walls. The y lack the regular orientation of cellulose and differ from it by being soluble in alkaline solutions and more susceptible to acid hydrolysis. It has been stated that hemicelluloses may include short-chain glucans; polymers of xylose, arabinose, galactose and glucose and possibly other monose units; or mixed polymers of sugar units and uronic acid units, usually methylated and sometimes acetylated. Past research on hemicellulose has been confined almost entirely to those present in entire plants, i.t. a mixture of all parts, or in a major single part as wood or straw. The hemicelluloses of range grasses, however, have been almost totally neglected. Some carbohydrates are believed to provide protection, by their hydrophilic properties, from extremes of temperature and from drought injury. All carbohydrates in the top growth of plants are digested to some extent by grazing animals. The information obtained from this study should serve as a beginning for further investigation which should eventually provide a basis to understand some of the processes of animal nutrition and plant physiology.

Library of Congress Subject Headings

Forage plants


Includes bibliographical references



Number of Pages



South Dakota State University