APPENDIX 



231 



Sampling errors^ of estimates of commercial forest area and inventory volume in the United States by 



region and State — Continued 





Commercial forest area 



Inventory volume 





Region and State 



Million 

 acres 



Percent sampling 

 error 



Billion 

 cubic 

 feet 



Percent sampling 

 error 



Date of 

 field work 





Total 



Per 



million 



acres 



Total 



Per 

 billion 

 cu. ft. 





Central Gulf: 

 Alabama. 



21.7 

 18.0 

 13.7 



.3 

 .3 

 .3 



1.4 

 1.3 

 1.1 



14.5 

 8.4 



7.5 



1.5 

 1.4 

 2.4 



5.7 

 4.1 

 6.6 



1961-1963 



Mississippi 



Tennessee 



1956-1957 

 1960-1961 



Total 



53.4 



.2 



1.3 



30.4 



1.0 



5.5 





West Gulf: 



Arkansas 



Louisiana 



Oklahoma 



Texas 



21.5 



16.5 



5.3 



12.0 



.3 

 .3 



.7 

 .4 



1.4 

 1.2 

 1.6 

 1.4 



12.7 



15.2 



1.6 



9.0 



1.2 

 1.6 

 4.2 

 2.6 



4.3 

 6.2 

 5.3 



7.8 



1957-1960 

 1953-1954 

 1955-1956 

 1953-1955 



Total . . 



55.3 



.2 



1.4 



38.5 



1.0 



6.1 









Total, South 



201.1 



.1 



1.5 



134.1 



.5 



5.5 





Pacific Northwest: 



Alaska 



Oregon 



Washington 



5.8 

 26.6 

 19.5 



1.2 

 .3 

 .5 



3.0 

 1.6 



2.2 



35.1 

 95.1 

 72.9 



1.7 

 1.2 

 1.0 



10.0 



11.7 



8.5 



1954-1962 

 1947-1962 * 

 1948-1960 5 



Total.. _ ._ 



51.9 



.3 



2.0 



203.1 



.7 



10.4 









Pacific Southwest: 



California 



Hawaii . . ..... 



17.4 

 1.1 



.6 

 4.3 



2.5 

 4.5 



55.3 



.2 



1.7 

 13.7 



12.6 

 6.4 



1962" 

 1957-1961 







Total 



18.5 



.6 



2,7 



55.5 



1.7 



12.6 





Northern Rocky Mountain: 



Idaho _ _ . 



15.8 



17.3 



1.3 



4.9 



.9 



.7 

 2.6 



.7 



3.6 

 3.0 

 3.0 

 1.5 



26.5 



26.8 



1.0 



7.4 



1.3 



1.9 



10.0 



2.7 



6.7 

 10.0 

 10.0 



7.4 



1947-1954 ? 



Montana 



South Dakota (W.) 



1948-1958* 

 1960 



Wyoming 



1957-1960 



Total 



39.3 



.5 



3.1 



61.7 



1.1 



8.3 





Southern Rocky Mountain: 



Arizona 



Colorado 



Nevada 



New Mexico _ _ 



3.8 



12.3 



.1 



6.1 



4.0 



1.5 

 .9 

 9.1 

 1.2 

 1.5 



3.0 

 3.0 

 3.0 

 3.0 

 3.0 



6.2 



17.3 



.2 



7.5 



5.8 



4.0 

 2.4 

 25.7 

 3.7 

 4.1 



10.0 

 10.0 

 10.0 

 10.0 

 10.0 



1951-1962" 

 1956-1959 



1952 9 

 1951-1962 9 



Utah 



1958-1961 



Total 



26.3 



.6 



3.0 



37.0 



1.6 



10.0 





Total, West 



136.0 



.2 



2.7 



357.3 



.6 



10.7 





Total, United States 



508.9 



.1 



2.5 



627.9 



.3 



8.5 









' Sampling error in percent in terms of one standard 

 error based on the most recently completed forest survey. 



2 Subsample in 1954 used to update 1937 data. 



3 1961 data used for one quarter of State. 



* Western Oregon completed 1961-62. Eastern Oregon 

 completed 1947-58. NFA inventories of a later date used 

 when available for national forest. 



5 Western Washington completed 1948-60. Eastern 

 Washington completed 1953-60. NFA inventories of a 

 later date used when available for national forest. 



« Subsample of plots established in original inventory 

 remeasured in 1962 and regression techniques used to 

 update entire original sample. Recently completed NFA 

 inventories used for national forest. 



' Northern Idaho completed 1947-51. Southern Idaho 

 completed 1950-54. 



8 Western Montana completed 1958. Eastern Montana 

 completed 1948. 



» Latest NFA inventory used for national forest. Re- 

 mainder by inventory and extrapolation. 



