A STUDY ON ESTABLISHMENT AND INVESTIGATION METHODS OF BAMBOO EXPERIMENTAL FIELD

The variation of basic investigation factors of bamboo stands such as volume, total weight of newly born bamboo individuals per year, density and d. b. h. (diameter breast height) are varied, with the least coefficient of variation in d. b. h. and largest in total weight of newly born bamboo individuals per year. Less variation was found in bamboo stands of grade I i. e. stand with high yield and more in stands of grade Ⅲ i. e. stand with low yield. For the measurement of total weight of newly born bamboo individuals per year, the size of sample plot for stand of grade I suggested is about 500 m2 and for that of grade Ⅱ and Ⅲ 600-800 m2 generally. Neither the shape of sample plot nor the location of the rectangular sample plot was found with apparent effect on experimental error.For the evaluation of volume or yield of bamboo stands, the simplest and fastest method found was to multiply the total number of bamboo individuals by the mean weight of bamboo individuals calculated from the mean value of the squared diameter in the sample plot. The average ratio of the deviation calculated by this method from real yield to real yield was less than 0.1%.For sample plots only with data of diameter of brow height (D1), it is possible to calculate the diameter breast height (D) from D1 using following formulae:D=0.02057+1.01767 D1 for stands of gradeI,D=0.16138+1.00546 D1 for stands of grade Ⅱ and D= 0.04155+1.01873 D1 for stands of grade Ⅲ.