﻿COTTONWOOD IN THE MISSISSIPPI VALLEY. 



17 



There is an important relation between the height of the stump 

 and the proportion of sprouts arising respectively from the root 

 collar and the top of the stump. 1 Of the two kinds of sprouts, only 

 the former is of practical importance from the standpoint of renew- 

 ing a stand commercially. Sprouts from the top of the stump are 

 dependent upon the stump for support, as they are unable at once 

 to form an independent root system of their own. Cottonwood 

 stumps, however, decay rapidly, and as the mechanical support of 

 the new sprouts thus becomes weakened they are easily sloughed off 

 and eventually are almost always thrown by the wind. The num- 

 ber of vigorous sprouts from the root collar decreases with the height 

 of the stump; other conditions being favorable, very low stumps 

 (below G inches) invariably produce vigorous sprouts. Very "little 

 dependence can be placed upon stumps more than 15 inches high to 

 sprout vigorously from the root collar. In fact, stumps higher than 



11 inches produce a disproportionately large number of sprouts from 

 the top of the stump. If dependence is to be placed upon sprouts 

 from the foot collar, it would therefore seem advisable to cut the 

 stumps as low as 6 inches, if possible, and certainly not higher than 



12 to 14 inches. Table 2 shows the relation between the height of 

 stump and the kind and vigor of sprouts. 



Table 2. — Relation between height of stump and kind and vigor of sprouts. 





. 



Aver- 



Aver- 



Aver- 









Aver- 



Aver- 



Aver- 





Height 



Num- 



age 

 number 



age 

 number 



of 

 sprouts 

 on top 



of 

 stump. 



age 

 number 

 of vig- 

 orous 

 sprouts 



on 

 stump. 



Aver- 

 age 



Height 



Num- 



age 

 number 



age 

 number 



of 

 sprouts 

 on top 



of 

 stump. 



age 

 number 

 of vig- 

 orous 

 sprouts 



on 

 stump. 



Aver- 

 age 



of 

 stump. 



ber of 

 stumps. 



of 

 sprouts 

 on root 

 collar. 



height 



of 

 sprouts. 



of 

 stump. 



ber of 

 stumps. 



of 

 sprouts 

 on root 

 collar. 



height 



of 

 sprouts. 



Inches. 











Feet. 



Inches. 











Feet. 



4 



11 



14 







14 



10.00 



23 



9 







42 



31 



5.58 



5 



16 



11 







11 



6.66 



24 



26 







26 



12 



6.25 



6 



21 



12 



2 



14 



7.25 



25 



16 







45 



20 



5.00 



7 



18 



9 



5 



12 



9.16 



26 



11 







38 



16 



4.50 



8 



12 



7 



14 



20 



9.33 



27 



14 







38 



18 



4.75 



9 



27 



13 



20 



25 



8.75 



28 



21 



1 



56 



18 



4.50 



10 



31 



5 



8 



13 



7.41 



29 



8 







46 



18 



4.66 



11 



20 



8 



2 



10 



8.25 



30 



36 







60 



20 



4.00 



12 



16 



9 



30 



39 



6.66 



31 



29 







51 



22 



4.16 



13 



32 



5 



48 



53 



7.00 



32 



31 







44 



15 



5.08 



14 



51 



7 



21 



28 



7.16 



33 



20 







54 



21 



4.50 



15 



42 



6 



17 



23 



7.66 



34 



27 







63 



14 



3.66 



16 



23 



3 



32 



35 



6.16 



35 



18 







37 



8 



4.25 



17 



57 



2 



36 



32 



7.08 



36 



25 







67 



10 



3.16 



18 



37 







42 



35 



7.16 



37 



13 







74 



9 



3.66 



19 



7 







62 



20 



6.00 



38 



9 







35 



10 



4.58 



20 



41 



1 



44 



30 



5.50 



39 



5 







57 



12 



3.41 



21 



23 







24 



18 



6.16 



40 



2 







65 



10 



3.16 



22 



10 







37 



22 



5.25 



41 



3 







61 



16 



4.58 



1 " The Cottonwood (Populus deltoides) : A Tree Study," Master's Thesis, by Julius V. 

 Hofmann, University of Minnesota, April, 1912. 



8471°— Bull. 24—13 3 



