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THE FORESTER. 



February, 



"The high price of lumber has not 

 failed to impress itself on the public mind," 

 says the Nashville American in an edi- 

 torial. "At this market alone, where 

 hardwoods are almost exclusively dealt in, 

 the price has in a year advanced from 25 

 to 33;^3 per cent. It is very likely that 



the demand for lumber of all kinds, both 

 in this country and Europe, is largely re- 

 sponsible for this increase in price; but 

 the high price, whether temporary or per- 

 manent, may well lead to the inquiry : 

 ' How is our supply of timber holding 

 out, and how long will it last?' 



Recent Publications. 



"Natural and Forest Reservoirs of the State 

 of New York," by G. W. Rafter, consulting 

 engineer, and included in the annual report of 

 the Commissioners of Fisheries, Game, and 

 Forests, is a very valuable article. 



The first part, which deals with the possi- 

 bilities for the development of water power, 

 shows the reasons why New York has hitherto 

 been unduly backward in this regard. With 

 the best natural facilities in the country, her 

 total horse-power utilization is s'ill dispropor- 

 tionately small. The hindrance has lain in the 

 inconsistency and insecurity of riparian legisla- 

 tion, which has not encouraged owners to invest 

 in improvements. New York has nothing par- 

 allel to the Mill Act of Massachusetts, whereby 

 manufacturers may exercise the right of eminent 

 domain and so possess the title to the waters they 

 might thus venture to conserve. 



The opportunities and necessities for such 

 conservation are then clearly shown. The pur- 

 pose being to equalize as far as possible the flow of 

 mill streams, from one month to another, storage 

 reservoirs at the head waters become the natural 

 means. Mr. Rafter explains that those hith- 

 erto projected have failed through the ignorance 

 of the builders in regard to rainfall and run- off 

 in the catchment basin, which to be of any real 

 service must have been determined for a con- 

 siderable period of years. 



There is then given in the most substantial 

 calculations, exactly the conditions necessary 

 for the establishment of successful reservoirs, 

 the volume of water that can be counted upon 

 for power from a stream having a known dis- 

 charge, and the cost per million cubic feet of 

 stored-up water for the needed operations. A 

 careful description follows of the method and 

 problems in the construction of the Indian Lake 

 Reservoir, the clearing of timber up to the flood 

 level, the making of the dam, everything down 

 to the estimate of costs. 



Besides this most instructive discussion of 

 water power and water storage, there is a section 

 on 'Why Forests Conserve Stream Flow." 

 This is a real help to American study of the sub- 

 ject. Its main value, perhaps, consists in its 

 sane and scientific manner no vague assertions, 

 no general opinions, but everything convincing. 



The author does not attempt to settle the con- 

 troversy once and for all. 



On the contrary he takes pains to state that 

 the observations and experiments necessary for 

 its settlement must extend over a number of 

 years. Meteorological data, as he points out, 

 are very dangerous evidence to trust, and, to be 

 of any use at all must have been collected and 

 averaged through a long series of seasons. 

 This, as yet, has not been accomplished (at least 

 not under the proper conditions) ; and rainfall, 

 temperature, evaporation, and all the other phe- 

 nomena of the weather, in their relations to 

 forest cover, remain ungauged. 



As an example of the problems included in 

 such research may be mentioned Mr. Rafter's 

 remarks on evaporation. From water to air, as 

 well as from any surface kept constantly wet, 

 the process is measured by a definite law and 

 formula. "The main difficulty, therefore," he 

 says, "in reducing evaporation from the ground 

 to a simple formula is largely due to uncertainty 

 of the water supply. The demands of evapora- 

 tion from the surface of the ground are contin- 

 uous, the same as from other surfaces, but con- 

 stant interruption, by either complete or partial 

 exhaustion of the available supply, complicates 

 the action so much that it renders expression by 

 formula apparently impossible. This sounds 

 like a sensible reason for discounting any sweep- 

 ing statement about the relative evaporations of 

 forests and farms, or cleared land. 



After similar evidence against the authority of 

 data about dew point, humidity, vapor pressure, 

 what the author calls a " tentative proposition " 

 is particularly taking and suggestive. It is * 

 " that the real reason why forested areas furnish 

 more water in the streams for a given rainfall 

 than do deforested areas, is because forests, on 

 the whole, consume less water than do deforested 

 and cultivated areas." Following this are a 

 dozen pages of most interesting and unanimous 

 data on the use of water by vegetation. 



The final inference is " that highly cultivated 

 farming areas will consume in surface evapora- 

 tion and plant transpiration from two to three 

 times as much water as averagedeciduousforests, 

 and from three to five times as much as average 

 evergreen forests." 





