26 BULLETIN 24, U. S. DEPARTMENT OF AGRICULTURE. 
TABLE 5.—Yield of cottoniwood stands on upland soil in Iowa and Minnesota. 
: 
| | Yield peracre, | 
| Average Scribner. 
Number | 5-. | at 
Location. | Age. | of trees | Tani eae Fests 3 IS see Remarks. 
< } ond . } 
Deb SESS | Sihigh ol To 12-inch|To 10-inch 
top. top. | 
Years Inches Feet. Bd. ft Bd. ft. | ; 
Lee County, Iowa -- 25 108 | 13.0 80 1, 700 | 5,100 | Scattered, with many 
associate species. 
Dos ae 25 8s 13.8 82 4,100| 6,600 Do. 
Allamakee County, 45 131 Losi) $4 12, 900 15,600 | Pure stand. 
Iowa. 
Jackson County, 50 80 18.3 100 15,800 | 18,100 | Very dense pure stand. 
Iowa. | 
Monona County, 55 | 88 16. 5- Ot 13,100 | 16,800 | In Missouri Valley, less 
Towa. | | humidclimate, dense, 
5 | "| _ pure. = 
Scott County, Minn- 56 25 24.8 | 107 15,000 | 18,100 | Maple,elm,ash, etc.,in 
| mixture. 
It is probable that some of these stands have been cut to a slight 
extent, but it is not lkely that on upland soil in this region cotton- 
wood will cut more than 20,000 feet per acre at 50 years of age. At 
ihis age, however, it has already reached maturity and is losing 
rather than gaining. Yields of between 15,000 and 20,000 board feet 
ought to be possible in 35 to 40 years. One or two plantations in 
Towa on good bottomland soil have yielded more, as may be seen 
from Table 6. 
¢ 
TABLE 6.—Yield of cottonicood on bottomland soil in Toa. 
a Average | | 
oe sce, wrmber | diameter Average | Yield Original 
: Seis per acre breast height. | peracre.| spacing. 
*| high. 
Years. Inches. Feet. : | Bad. ft. Feet. 
Harrison County. .°) {91-8 = ese eee 34 126 14.5 | 87 | 23,850 7k by 6 
IMontoc County = s205 soa eee 35 137 13.3 77 24,500 8i by 8 
| 
At least one of the plantations has occasionally been thinned, 
Moreover, the trees had plenty of room for early growth, and it is 
probable that they were cultivated for the first few years. In the 
case of these plantations, however, the estimates take in all straight 
logs to a top diameter of 6 inches, for even such small-sized material 
is actually sawed up for farm use. Considering, however, only logs 
10 inches and over in diameter, northern stands of cottonwood will 
probably seldom yield more than two-thirds as much saw timber as 
stands of the same age in the lower half of the valley. 
MANAGEMENT. 
ADAPTABILITY OF COTTONWOOD. 
If cottonwood stands are to be maintained permanently some sys- 
tem of management is essential.- Its demand for plenty of direct 
