TENDING OF WOODS DURING EARLY YOUTH. 195 



to protect forests against them are taught in Forest 

 Protection. Several species of both insects and fungi 

 are specially dangerous to young forest plants ; hence it 

 is the duty of the forester to watch carefully his re- 

 generation areas, and to remove and destroy all plants 

 as soon as they are attacked, and even sickly plants, so 

 as to prevent the spreading of the evil. In many cases 

 it is necessary to let areas lie fallow for a few years, 

 until species, which breed in the stools and the refuse of 

 the old wood, have disappeared again. As an illustration, 

 Ilylobius abietis, the pine weevil, may be mentioned, 

 which frequently becomes disastrous to young Scotch 

 Pine and Spruce woods. 



2. Preservation of a proper Density of the Crop. 



In the majority of cases it occurs that, for one reason 

 or another, some of the plants fail, thus causing smaller 

 or greater blanks. All these must be filled up without 

 loss of time. As long as the young crop is only a few 

 years old, recruiting can be done with plants of the 

 same kind as the original crop. Such plants may 

 be obtained from nurseries, or, in the case of natural 

 regeneration, they may be taken from places where 

 the plants stand too close together. Direct sowing is 

 also done, but planting with strong plants is preferable, 

 because these have a better chance of keeping pace with 

 the rest of the crop. 



If the original crop is already so far advanced that 

 plants of the same species are not likely to catch it up, 

 the recruiting must be done with a quicker-growing 

 species; if this is not feasible, with a shade-bearing 



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