24 BULLETIN 24, U. S. DEPARTMENT OF AGRICULTURE. 
TABLE 3.—Growth and yield of cottonwood (Populus deltoides Marsh) in pure, 
fully stocked stands in the Mississippi Valley. 
| Number of trees | Average size Yield per acre Average annual yield per 
per acre. = aoe ; acre. 
Age. | x : ens 
14inches} All dameter : Sten: |. 9S Stem | Scribner 
| and over.| trees. ee Height.| ood. Hondo Doyle: | Sood. | decimal. | Dev!e- 
| | (ite Fhe ae 
| Years. | Inches. | Feet. | Cu.ft.| Bd.ft.| Bd.ft.| Cu.ft.| Bd.ft. Bd. ft. 
5 een a =e 2.0 22 G50n 2222 Ss eee 130 ost aE 
| 6 ee Ie ee 2.8 29 S105) 2a 4) sess 146 
7 Be 1, 450 3.5 SG: eed 0258 4 eee siete 146 : 
8 = 1, 163 4.2 AB OVE 250 Gy oe ea i See 156 : 
9 Ee 900 5.0 AS ah 15005 rae S| Pe eee 167 2 3a 
10 pa 699 5.7 On| A SOO ite Se eens esos 180 
11 a 508 6.4 GEE 25 SP geese 198 F 
12 3 | 452 Tica 672} 2,600) |e Se | 200 217 - 17 
13 8 | 379 7.8 72 | 3,050 800 700 235 62 a4 
14 15 | 320 8.5 76 | 3,500 | -1,600 | 1,300 250 114 93 
15 22 276 9.2 81 | 3,850} 2,400 | 1,900 257 160 127 
16 29 243 | 9.8 8 | 4,150} 3,200} 2,600 259 | 200 163 
17 | 34 | 217 10.5 88 | 4,400 | 4,000! 3,300 259 235 194 
18 37 | 195 tie 92 | 4,575 | 4,900) 4,100 254 272 228 
19 40 | 178 be 95 | 4,750} 5,800; 4,900 250 305 258 
20 43 163 12.3 97 4,900 | 6,600 | 45,70€ 245 330 285 
PAL) 45 150 12.8 100 | 5,025 7,600 6,500 239 362 310 
22 | 47 140 13.4 102 | 5,125} 8,600} 7,500 233 391 341 
23 | 49 130 13.9 104 | 5,250 | 9,600; 8,400 228 4I7 365 
24 | 50 121 14.5 106 | 5,350 | 10,700 | 9,500 223 446 396 
25 52 114 15.0 108 | 5,450 | 11,900 | 10,700 218 476 428 
26 53 106 15.5 109 | 5,525 | 13,200 | 12,000 213 508 462 
27 a4 99 16.0 111 | 5,600 | 14,700 | 13,400 207 d44 496 
l 28 50 92 16.5 112 | 5,675 | 16,300 | 15,100 203 | 582 540 
29 By) 86 16.9 114 | 5,750 | 18,100 | 17,100 198 624 590 
36 55 80 17.4 115 | 5,825 | 20,300 | 19, 200 194 677 640 
31 By) 75 17.9 116 | 5,875 | 22,700 | 21, 400 190 732 690 
32 By) 70 18.3 117 | 5,950 ; 24,900 | 23,500 186 778 734 
33 55 66 18.8 119 | 6,025 | 26,800 | 25,300 183 812 767 
34 5A | 62 19.3 120 | 6,075 | 28,300 | 26,600 179 832 | 782 
30 53 a9 19.7 121 | 6,150 | 29,400 | 27,500 176 840 786 
| 36 52 57 20. 2 123 | 6,200 | 30,100 | 28, 200 172 836 7 
37 phil 753 20.6 124 | 6,275 | 3C, 400 | 28, 700 170 822 776 
38 50 | 51 21.1 125 | 6,325 | 30,700 | 29, 100 166 808 766 
39 49 | 50 21.5 126 | 6,375 | 30,900 | 29,300 163 792 751 
40 | 48 49 22.0 127 | 6,425 | 31,000 | 29,300 161 775 733 
41 | 46 | 48 22.4 128 | 6,475 | 31,000 | 29, +00 158 756 717 
42 45 45 22.9 129 | 6,525 | 31,100 | 29,500 155 740 | 702 
43 44 | 44 23.4 130 | 6,475 | 31,000 | 29,500 153 721 686 
44 43 43 23.8 | 131 | 6,625 | 31,000 | 29, 0CO 151 705 670 
45 42 42 24.2 | 132 | 6,675 | 30,900 | 29,000 148 687 656 
46 40 40 24.7 133 | 6,725 | 30,800 | 29,500 146 670 641 
47 | 38 38 25.1 134 | 6,775 | 30,700 | 29,500 144 653 628 
48 Of | 37 25. 6 | 135 | 6,825 | 30,600 | 29,500 142 638 615 
49 34 34 26.0 136 | 6,875 | 30,500 | 29,500 140 622 602 
50 | 32 32 26.5 136 | 6,900 | 30,300 | 29, 400 138 | 606 588 
Similarly, the current annual production in cubic feet or cords 
per acre culminates at the age of 12 years, at which time approx- 
imately 500 cubic feet per acre annually is being produced. The 
average annual growth, however, continues to increase up to 16 years, 
when it attains 255 cubic feet per year, against onl 221 cubic feet 
at 12 years. It is plain, therefore, that if the object of growing cot- 
tonwood is to produce the maximum amount of solid wood per acre 
per year, a rotation of approximately 16 years will give the desired 
results. The reason why the average annual growth in board feet 
per acre culminates later than the average annual production in cubic 
feet is because the board-foot production does not begin until the 
