4f) A N N UAL BfflFORT- OK hKl'AKTMKNT OF A( iKK I'LTL'IU;, 194 
STATUS OF CONTROL WORK BY REGIONS 
The status of control work at the end of 1939 is shown in table 7. 
Tahlb 7.- Status of blister rust control work in/ regions on in,-, .u, /.<<.;<< 
Region 
Control 
areas ini- 
tially pro- 
tected" 
Control areas 
reworked 
subsequent 
to initial 
protection 
Ribes destroyed 
Kxecu i i ve 
labor 
Northeastern States ? 
Acres 
10. 4*2. 6ft* 
5. 21 fi, 22S 
2. 770, 328 
1, 826, 694 
780,251 
36. 619 
Acres 
3. 742. 997 
899.018 
267, 051 
27.5. 619 
191, 709 
1,962 
Number 
262. 043. 040 
25,821.953 
204, 630, 483 
395. 427. 774 
123. 403. 191 
1. 583. 306 
Man-day $ 
2. 4*2.3*0 
229,666 
813,799 
1,721,050 
550,796 
13,896 
Southern Appalachian States 
North Central States... - 
Western white pine States (Idaho. Montana, 
Washington) 
Supar pine States (California and Oregon) 
Rocky Mountain States '(Colorado and Wyoming). 
Total 
21, 112. 818 
5, 378, 416 
1, 012. 909, 747 
5.811,567 
> The figures shown are net totals to Dee. 31,1939, and do not include worked areas that were later removed 
from control-area status owing to their reversion to nonpinc-producing types as a result of fire, cutting, or 
other causes. 
* The work in Colorado and Wyoming represents experimental Ribes eradication in stands of limber. white- 
bark, and bristlecone pines on national forests to develop practical control measures for the Rocky Mountain 
retrion In advance of the spread of the rust. The acreages shown for these 2 States are not at present con- 
sidered as Dart of the commercial white pine areas of the United States. No work was carried on in these 
States during 1939. 
The aggregate acreage of control areas initially protected from 
rust by the eradication of Eibes, as shown in table 7. represents over 
two-thirds of the acreage needing protection. Progress in Ribes 
eradication differed in the various white pine regions owing to 
differences in the time of rusl invasion, in the period during which 
control activities have been under way, in the abundance of Rib( », 
and in the difficulties of working conditions. In recent years the 
availability of emergency-relief funds has provided a much larger 
amount of needed labor and has made possible more rapid coverage 
of control areas in all regions. 
SPKKAD OF BLISTKK RUST IN 1939 
During 1939 there was no large extension of the limits of the known 
infected area in this country. Spread of the nisi within the infected 
parts of the different regions varied considerably, being very slight 
in the sugar pine region and quite general in the North Central region. 
Such variations result largely from the influence of prevailing 
weather conditions on rust development and spread and are normally 
to be expected. 
In the Appalachian region south of Pennsylvania, blister rust wa- 
found for the first time on Ribes in Kent County, Del., Calvert and 
Prince (Jeorges Counties, Md.: Albemarle County, Ya.: and Preston 
County, W. Ya. On white pine it was found for the first time in 
Greene < 'ounty, Ya., and in Hardy. Tucker, and Pocahontas ( fcrant ies, 
W. Ya. This represents an extension of the disease to the south- 
ward on Ribcx of one county in Delaware and two counties in Mary- 
land. Within a few of the previously known infected counties in 
the southern Appalachian region there was general infection on Rtbi - 
and some increase oi the disease on white pine. 
