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Plant physiologists and others interested in the periodic accumulation and depletion of the reserve carbohydrates in plants have long recognized the need for a rapid method for the estimation of the readily available carbohydrate fraction. This is especially true in applied studies such as those concerned with the efficient management of pasturage or forage plants. Undoubtedly, many worth while projects of an applied nature have never been undertaken because of the lack of time to carry out the tedious fractionation of the individual carbohydrate constituents.H. WEINMANN (9) has recently published a method for the determination of the total available carbohydrates in plant material by a single determination. The present paper reports a summary of the studies on the analytical aspects of the method as well as its applicability to the study of the seasonal trends in the carbohydrate reserves in the storage orgalls of switch cane (Arundinara tecta), a plant readily grazed by eattle. MethodsThe samples were taken at monthly intervals, or oftener, from a restricted portion of a uniform stand of switch cane in the Hofmann Forest in eastern North Carolina. The cane averaged about four feet in height.Small blocks of sod were dug with stems intact and washed free of soil. Roots were removed and discarded. Rhizomes (including the underground portion of the stems), aerial stems, and leaves were divided into separate samples: 250 grams each of stems and rhizomes and 150 grams of leaves.To facilitate drying, stems and rhizomes were cut into short segments an inch or less in length. Leaves were collected only during the months when there was a reasonably abundant supply (June through December).There was some variation in the drying procedure due to the equipment available. The first five samples (April through June, 1947) were held in an oven at 1000 C. for approximately onie hour and then dried to constant weight at 70°to 750 C. without forced draft. The remainder of the samples were dried under forced draft at 70°C. The collections were made at a point more than 100 miles from the laboratory and, therefore, several hours (usually 6 to 18) elapsed before the samples were placed in the drying oven. After the samples were dried, they were shipped to the

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