18 



PBACTICAL FOKESTBY. 



old trees about the openings are gradually cut away, and the groups 

 of young growth, spreading from the original openings like drops of 

 oil on water, finally meet. 



This is one of the simplest and most useful of all the systems, and 

 when the openings are made small at first no other is so safe. It is 

 especially adapted to small pieces of forest, such as woodlots, because 

 it is simple, and because it assures the safety of the forest even with 

 very little skill or care on the part of the owner. 



The strip system. — In nearly every wooded region of the United 

 States a tornado occasionally destroys the trees in a long and narrow 

 belt through the forest. Fire often follows and clears the strip by 



Fis. 10.— Mimic forest, showing distribution of young growth under the group system. 



burning up the fallen timber. Seeds then fall in the opening, carried 

 from the trees on either side, the seeds germinate and grow, and the 

 reproduction of the forest takes place. 



When the ax takes the place of the tornado and the timber is logged 

 instead of being burned, the strip system is apphed. Eeproduction 

 follows from trees on either side, as before. The strip system consists 

 in cutting long narrow openings in the mature timber instead of the 

 circular openings of the group system, to which it is similar in many 

 ways. It is simple and effective when natural reproduction is good, 

 and well suited for extensive operations in places where careful work 

 is impossible. The strips are usually not over 100 yards in width. 

 Where the soil is dfy, they are run east and west to protect the young 

 growth against the sun, and are comparatively narrow. If there is 

 serious danger of windfall, they lie at right angles to the direction of 

 the wind. 



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