208 



TIMBER RESOURCES FOR AMERICA' S FUTURE 



ponderosa pine through southern Idaho and 

 eastern Oregon, and small outbreaks are currently 

 active elsewhere in Idaho, as AveU as in parts of 

 Washington, Montana, and California. During 

 the past 8 years, it has killed outright at least 46 

 million board-feet of high-quality timber in the 

 Pacific Northwest and has transformed thousands 

 of good trees into high risks likely to succumb 

 to insect attack. 



Miscellaneous diseases not listed individually, 

 through their attacks in 1952, had an impact on 

 growth of over 2,300 million board-feet. This is 

 12 percent of the impact from all diseases. The 

 group includes many stem rusts, root I'ots, leaf 

 and needle diseases, and forest losses from such 

 epidemic diseases as the Dutch elm disease, 

 phloem necrosis of elm, and persimmon wilt. 



T^jvANCEs Being Made in 

 Disease Control 



Disease Surveys, the First Step 

 Toward Control 



Forest disease surveys are essential to learn 

 what diseases we have and something of their 

 importance, to detect new threats, to appraise 

 the extent and damage of known diseases as an 

 aid in planning, and to delimit outbreak areas for 

 control purposes. For the initial detection of 

 new disease threats, considerable dependence is 

 placed on the ever-growing field force of foresters, 

 pathologists, other specialists, and woods workers. 



Appraisal surveys, so essential to gage the 

 scope of attack and the possibilities for and costs 

 of control, received great impetus with the pas- 

 sage of the Forest Pest Control Act of 1947, the 

 functioning of which is explained in the final part 

 of this section. The appraisal survey program has 

 been successfully applied to oak wilt, pole blight, 

 larch canker, swectgum blight, and birch dieback. 



However, appraisal surveys do not meet the 

 full needs of control planning, estimation of 

 damage, and the determination of research 

 required. Control surveys are therefore made 

 to locate the stands or trees requiring treatment. 

 They led to the control of larch canker in New 

 England, and arc in wide use in the blister rust 

 control program and in the suppression of oak 

 wilt in the Eastern and Southern States. The 

 States have played a vital part in the financing 

 and operation of the blister rust and oak wilt 

 surveys, and are assuming a major role in forest 

 pest detection and siu'vey in general. 



Direct Control Necessary 

 Against Some Diseases 



In the sense that it is used liere, direct control 

 refers to eft'orts and expenditures made specifi- 



cally and solely for controlling a given disease, and 

 not those activities worked in as a part of normal 

 silviculture. Most current forest disease control 

 is considered indirect in that it is effected tlu'ough 

 adjustments in forest management. Of the few 

 current programs of direct disease control, the 

 largest, by far, is the blister rust program. Three 

 of the eight native white pines in the United 

 States — eastern and western white pines and 

 sugar pine — are being protected against blister 

 rust. 



Federal, State, and private agencies cooperate 

 in blister rust control. Federal funds are made 

 available to the Department of Agriculture for 

 overall leadership, coordination, and technical 

 direction, and for control on national-forest and 

 non-Federal lands in cooperation with State and 

 private agencies. The Department of the Interior 

 receives Federal funds for Indian, national park, 

 and other lands under its supervision. Satis- 

 factory control involving the removal of currant 

 and gooseberry plants, the alternate hosts of the 

 disease, from the control areas has been establish- 

 ed and is being maintained on three-fourths of 

 the Nation's primary white pine areas. The 

 remaining one-fourth includes higli-hazard areas 

 in the northern Lake States, Idaho, and parts of 

 Oregon and California. 



Several States east of the Mississippi River have 

 active oak wilt control programs, some of which 

 are in cooperation with the Federal Government. 

 The tree removal and treatment phase of this 

 program was, in 1952, carried on entirely by the 

 States. 



Prescribed fire is now widely used in the South 

 to control the brown spot in longleaf pine seed- 

 lings. Allien properly used, these fires consume 

 diseased foliage with little damage to the trees, 

 checking subsequent infection long enough to 

 stimulate growth. Since such burns also reduce 

 the forest fuel, reduce grass competition, and 

 at least temporarily improve spring forage, only 

 part of their cost is chargeable to brown spot 

 control. 



Only recently have large-scale attempts been 

 made to control dwarfmistletoe by cutting 

 infected trees, although the eft'ectiveness of mistle- 

 toe elimination as a means of control has been 

 apparent for several years. In 1952 the Federal 

 Government supported such a program on some 

 of the national park and Indian lands of the 

 Southwest. 



Some larch cankei-s, in addition to those found 

 and removed following discovery of the disease 

 in 1927, were found by disease survey crews in 

 1951 and 1952. The infected trees were destroyed. 



Other current direct control of forest diseases 

 includes small-scale eft'orts against a large number 

 of diseases both in plantations and natural stands. 



The expenditures for the direct control of forest 

 diseases in 1952 totaled $3,857,300, approximately 



