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WRIGHT : THE GENUS DIOSPYROS 
Rate of Growth. 
The genus Diospyros, in Ceylon, possesses some of the 
most slowly-growing tropical trees. In the seedling and 
sapling stages, np to the first ten or twelve months the growth 
takes place at a fairly rapid rate ; seedlings two months old 
may measure, above ground, from 30 to 150 mm. according to 
the length of the hypocotyl, but in two and a half years the 
total height may exceed 3,300 mm. ; saplings ten years old 
may measure less than this, and the subsequent growth takes 
place at a slow rate. The following are the dimensions of 
two and a half years old saplings raised in the same plot at 
Peradeniya :— 
Species. 
Height. 
mm. 
Circumference. 
mm. 
D. montana ... 3,610 (11 ft. 10 in.) ... Ill 
D.Ebenum ... 1,828 (6 ft.) 84 
D. Embryopteris ... 1,220 (4 ft.) ... 81 
D. quæsita ... 610 (2 ft.) ... 38 
Some species never develop into large trees, e.g ., D. acuta 
and D. pruriens, but the majority of Ceylon species attain 
huge dimensions, particularly D. sylvatica, D. crumenata, and 
D. affinis. There are, however, very few trees of known age, 
and exact information cannot therefore be obtained. There 
is one specimen of D. quæsita in the gardens, which, though 
known to be over sixty years old, measures only 472 mm. in 
circumference and a total height of about 14 metres ; this, 
however, is one of our slowest growing species ; other 
species, notably D. Embryopteris and D. montana, probably 
grow at a much quicker rate. 
Sample plots for observing the rate of growth have been 
established by the Ceylon Forest Department, and yearly 
observations have been made on selected trees in the various 
forests ; the results are, however, at great variance. 
Broun states that after reaching a circumference of 914 mm. 
(3 feet) D. Ebenum is very slow growing, and that the tree 
may reach a circumference of 457 mm. (1 foot 6 inches) at the 
age of 25 years, 914 mm. (3 feet) at 75 years, 1,372 mm. (4 
