ANOTHER WORD ON "LIGHT BURNING" 



BY FILIBERT ROTH, DEAN OF FORESTRY, UNIVERSITY OF MICHIGAN 



STEWART EDWARD WHITE in the Sunset Maga- 

 zine of March explains "light burning," and recom- 

 mends it as a regular practice. 



An artist in popular writing, White did this so well 

 that California is quite stirred up, and lined up in two 

 camps, and the matter is truly serious. 



White is not only clever, but from his point of view 

 he is also right, and the truth of what he claims seems 

 so evident that there is no use in disputing. He makes 

 two points : 



Fires destroy "bugs." 



Regular burning prevents accumulation of debris, and 

 consequently prevents large fires. 



The first claim needs no consideration ; it is new, un- 

 proven and contradicts the experience of 100 years. The 

 "bugs" (here the bark beetles), are encouraged and 

 not discouraged by injuring pine trees. But this is very 

 secondary. 



The second and important point is well taken. Light 

 burning with raking about the trees is an old practice 

 in the South, and has successfully protected thousands 

 of turpentine orchards. Simply burning the woods at 

 frequent intervals has kept millions of acres of Southern 

 pinery "clean" of brush, young trees and debris and 

 thus has added to their safety from fire. "Use fire to 

 fight fire," was advocated by the Michigan Forestry 

 Commission years ago. 



White's chief argument may be stated thus : Nature 

 has maintained forests for untold centuries, she has had 

 fires and bugs and storms and ice and all the other trou- 

 bles and yet she has given us the most beautiful and useful 

 stands of timber, a joy to see, and valuable beyond com- 

 pare. This argument not merely seems true, but is true. 

 If man would leave nature alone, as he did in the past 

 if he would not log and lumber, if he would not clear 

 land, travel, etc., nature would certainly go on indefinitely 

 and maintain beautiful forests. But this if is not ful- 

 filled and cannot be in the future ; we do and we must log, 

 build roads and railways, we clear the lands, we travel 

 and we people the forests. 



This White knows and it is to protect the forest 

 against all these new enemies, as well as the old, that 

 he recommends light burning as nature's great remedy 

 to perpetuate the forest, whether this method will pro- 

 tect, at what cost in money and in injury to young and 

 old trees, whether it can be made as effective as the 

 protection now begun (for it is not one-fifth organized 

 as yet), all this can be tested by experiment. 



To most foresters the experience of the past is quite 

 sufficient to fill them with apprehension, but being open- 

 minded, there is no opposition on their part to meet 

 experiment, but rather against a campaign which rests 

 on inference and is not supported by experiment. 



Since White bases his argument on the success of na- 

 ture it is interesting here to consider how far she has 



really been successful and how far nature failed to work 

 even without all the man-made difficulties of lumbering, 

 clearing, etc., and also how far she relied on the light 

 burning where she did succeed in building up stands of 

 well-cleaned, now useful timber. If we leave out the 

 hardwood district where fires rarely occurred and con- 

 sider only the large pinery regions of the United States, 

 this seems true: 



Here in Michigan, white pine and Norway pine made 

 stands of 75,000 feet board measure per acre and over; 

 but 50,000 feet per acre for an entire forty was rare; 

 25,000 feet (a million forty), was "fine" timber; the old 

 stock figure for pine was 5,000 feet per acre for large 

 areas. Even doubling this old stock figure of 5,000 

 feet, and allowing 10,000 feet per acre as average, na- 

 ture seems to have been about 20 per cent efficient. From 

 large caliper surveys in the southern longleaf and short- 

 leaf timber it is apparent that, for the long rotation 

 with which nature worked she was not over 40 per cent 

 efficient, even in real forest, to say nothing of the 

 large areas in which she had nothing to caliper or to 

 cut. In the Rocky Mountain Forests, or pinery, nature 

 did maintain forest, it is true, but her success was even 

 less than in the Lake Region and South. She burned 

 altogether too freely; large areas turned to prairie; 

 parks, south slopes and foothills, often the very best of 

 sites were without timber, and taking the entire area 

 of lands fit to raise timber and from our utility stand- 

 point, best suited to timber, nature was probably not 

 over 20 per cent efficient. The fine stands of lodgepole, 

 yellow and white pine which she did produce, certainly 

 did not develop under repeated fires, but were clean 

 timber because they started in dense stands which would 

 certainly have been destroyed if ever set afire. That 

 nature burned irregularly, that large areas have not 

 seen fire in a century is amply proven by any survey in 

 lodgepole, which shows that this pine usually starts in 

 dense thickets, at times so dense as to stagnate for many 

 years. The California mountains are not very different 

 from the Rockies. With extraordinary land and climate 

 for the production of timber, with species which com- 

 monly grow to the age of 300 years and more, and with 

 numerous stands of over 100,000 feet per acre, what is 

 the average stand over the California forest area? Why 

 has nature failed to cover fine forest sites with timber? 

 What is the area .of all that foot hill country covered 

 with brush and forage stuff? Why the large areas 

 where brush has followed the timber and will prevent 

 timber growth for years? 



Nature has done well ; in her household chaparral may 

 be as good as sugar pine, but from the standpoint of to- 

 day and of our industrial people, her success is about the 

 same as nature's effort at fruit growing with her huckle- 

 berry crop every 10 years, her wild cranberry and straw- 

 (Continued on page 572) 



MS 



