WILLOWS : THEIR GROWTH, USE, AND IMPORTANCE. 



13 



diameter growth gain their lead over the average trees during the 

 first two decades. By thinning, the diameter growth can be made 

 more sustained. 



Table 3 is based on measurements of 34 trees in Arkansas with 

 stumps 2.5 to 3.2 feet in diameter and 42 to 63 years old. Soil, a 

 rich, moist bottom land. The trees when plotted were divided into 

 three classes based on diameter growth. The minimum growth 

 given in the table is the average for the slowest growing trees; the 

 average growth is for the trees growing at a medium rate and the 

 maximum growth is an average for the fastest growing trees. Neither 

 the minimum nor the maximum growth is the slowest or fastest 

 found for individual trees. 



Table 3. — Diameter growth of black willow, Phillips County, Ark. 





Diameter, breasthigh. 



Increase in diameter 

 periods. 



by 5-year 



Age. 















Minimum. 



Average. 



Maximum. 



Minimum. 



Average. 



Maximum. 



Years. 



Inches. 



Inches. 



Inches. 



Inches. 



Inches. 



finches. 



5 



1.4 



2.6 



3.9 



1.4 



2.6 



3.9 



10 



3.3 



5.6 



7.9 



1.9 



3.0 



4.0 



15 



5.3 



8.5 



11.4 



2.0 



2.9 



3.5 



20 



7.5 



11.1 



14.4 



• 2.2 



2.6 



3.0 



25 



9.5 



13.5 



17.3 



2.0 



2.4 



2.9 



30 



11.5 



15.6 



19.8 



2.0 



2.1 



2.5 



35 



13.3 



17.5 



22.1 



1.8 



1.9 



2.3 



40 



15.1 



19.4 



24.3 



1.8 



1.9 



2.2 



45 



16.6 



21.2 



26.3 



1.5 



1.8 



2.0 



50 



18.1 



22.8 



28.2 



1.5 



1.6 



1.9 



55 



19.6 



24.3 



29.9 



1.5 



1.5 



1.7 



60 



21.0 



25.7 



31.6 



1.4 



1.4 



1.7 



Table 4 is based on measurements of 76 trees in Mississippi with 

 stumps 16 to 34.6 inches in diameter inside bark and 36 to 58 years 

 old. Soil, a rich, moist bottom land. 



Table 4. — Diameter growth of black willow, Jefferson County, Miss. 





Diameter, breasthigh. 



Increase in diameter by 5-year 

 periods. 



Age. 















Minimum. 



Average. 



Maximum. 



Minimnm 



Average. 



Maximum. 



Years. 



/ii<' lit:. 



Inches. 



Inches. 



Inches. 



Inches. 



Inches. 



5 



1.9 



3.1 



4.9 



1.9 



3.1 



4.9 



10 



3.9 



6.5 



9.0 



2.0 



3.4 



4.1 



15 



5.9 



9.5 



12.6 



2.0 



3.0 



3.6 



20 



7.5 



12.2 



15.9 



1.8 



2.7 



3.3 



25 



9.0 



14.4 



IX. 7 



1.5 



2.2 



2.8 



30 



10.4 



16.2 



21.4 



1.4 



1.8 



2.7 



u 



11.7 



17.9 



23. 8 



1.3 



1.7 



2.4 



■10 



13.0 



10.:! 



26.0 



1.3 



1.4 



2.2 



4.0 



14.2 



20.8 



27.8 



1.2 



1.5 



1.8 



60 



16.4 



22.2 



29.3 



].2 



1.4 



1.5 



66 



10.7 



2.i. .', 



30. 7 



L3 



1.3 



1.4 



60 



17.7 



21.7 



31.8 



J.O 



1.2 



1. I 



