CHEMICAL CHANGES WITH MATURATION OF THE BAMBOO SPECIES PHYLLOSTACHYS PUBESCENS

Bamboo chemical properties were measured at three different heights from one-, three- and five-year-old plants and at three different radial positions from the three-year-old culms of Phyllostachys pubescens grown in south-eastern USA. Small but significant increases in holocellulose and alpha-cellulose contents were detected from the base to the top of the culm at all three ages. In contrast, no significant differences in Klason lignin and ash were detected. The increases in carbohydrate content with age correlated with increases in specific gravity. Alcohol-toluene extractive content increased from the base to the top of the stem in the three-year-old and five-year-old bamboo and showed a continuous increase with age. The epidermis had the highest extractive and ash contents and the lowest holocellulose and a-cellulose contents. The outer layer of the stem had the highest holocellulose, cc-cellulose and Klason lignin contents and the lowest extractive and ash contents. The chemical content and specific gravity of bamboo stabilizes at about three years of age, which is an appropriate time for harvesting.