Science and Teaching of Forestry. 



composition of soils and of the various forest products ; particularly 

 with vegetable physiology, the vital processes of trees and other plants ; 

 with descriptive botany for the discrimination of species, and with 

 entomology as to the insect foes and friends of the trees. It is necessary, in 

 fact, that the theory of the healthy culture of trees, and its study in the lecture- 

 room and laboratory, must be accompanied by that of the art of forestry, so far 

 as it concerns sowing, planting, protecting and such pruning and thinning as 

 the health of the trees require. It is as essential to the estate manager who 

 plants for ornament, recreation, or game covert, as to him who plants for 

 profit in timber. 



Forest administration deals with the realisation of the crop to the best 

 advantage. The leading principle of this science is that the forest as a 

 whole be regarded as capital, and that the interest thereon is the amount 

 of wood formed in the year. This is the greatest amount of timber that 

 ought to be removed in the year. 



The methods by which this result is approximated are various ; but 

 there are four chief plans which we will consider in what is their chrono- 

 logical and natural order. They are felling by selection, or Pldnterbetrieb; 

 clearing by compartments, or tire et aire, felling by rotation of area, or 

 FachiverJce Methode, with artificial planting, and the same method with 

 reproduction by means of natural seeding. 



The first of these, felling by selection, or Planterbetrieb, is the primitive 

 system, if system it can be termed, in all countries. The forester either 

 fells just such trees as he wants over the whole forest area, or he takes all 

 those of full age each year, so that there will be a corresponding number 

 reaching maturity the next year. The drawbacks to this system are, 1st, its 

 disregard of the annual increment of the forest in cubic feet of timber ; 

 2nd, the difficulty of supervision when operations are spread over so large 

 an area, and, 3rd, the damage done to seedlings and saplings all over the 

 forest in removing the felled logs. This method is virtually followed in 

 many small English woodlands and private forests in Germany ; but the 

 yield it gives is both uncertain and less in amount than that of more 

 scientific methods. It has, however, been modified in some cases so as to 

 resemble the French system of tire et aire. The forest is divided into 

 twenty blocks, and in the first year all trees from eighty to a hundred years 

 old are felled in block 1 ; in the second all trees from eighty-one to a 

 hundred-and one in block 2 ; and so on. Thus whilst in the twentieth year 

 the trees felled will be from one hundred to one hundred and twenty years 

 old in the twenty-first they will be from eighty to one hundred. 



In the French system of tire et aire, now abandoned, a period called a 

 revolution was fixed for the clearing of all existing trees, natural seeding 

 being relied on for reproduction. The forest was then divided into as many 

 compartments as there were years in the revolution, one being felled each 

 year, with the exception of a few standards left as seed-bearers. It was 

 found in practice that little dependence could be placed on this unsheltered 

 seeding, and that not unfrequently trees of a quite distinct species sprang 

 up, thus changing the character of the forest for a generation or more. 

 This system was superseded in France by the German Fachwerke Methode 

 about fifty years ago. In the Scotch plantations it is still followed with 

 very satisfactory results, with the modification that each year's subdivision 

 of the forest area is entirely cleared and then replanted. Thus the trees are 

 all felled at one age, and those in any compartment are also all of one age. 



Hartig, the father of German forestry in Nassau, at the beginning of the 

 century, and Cotta, in Saxony, some ten years later, laid the foundation of 



