30 WORKING PLAN FOR FOREST LANDS NEAR PINE BLUFF, ARK. 



the first one hundred years the yearly average growth in height is 

 0.83 foot, and for the first twenty years 1.5 feet, (See tig. 6.) 



Relation of age to merchantable contents. — The curve here given 



20 



40 



60 



80 



160 180 200 220 240 



100 120 140 

 A6E — YEARS 

 Fig. 5.— Diagram showing the diameter growth of Shortleaf and Loblolly Pine on the basis of age. 



shows the volume growth in board feet for Shortleaf and Loblolly 

 Pine, the contents being calculated according to Doyle's Rule. 



Between 80 and 140 years of age the Shortleaf Pine increases very 

 uniformly in merchantable contents, after which age the rate of 



