Periodical Literature. 281 



cent, were killed, showing the plantations to have borne the 

 drought better than the sowings, made in both cases in furrows. 

 In the oak cultures, sowings showed very little loss ; plantings of 

 small stock 12 per cent. ; plantings of saplings 30 per cent. Here, 

 however, the good sites involved explain the small loss in the 

 sowings. In pine stands underplanted with spruce, 50 per cent, 

 were lost. The underplanted spruce in oak, beech and larch in 

 the Harz Mountains was entirely lost. Beech of natural re- 

 generation was lost to the extent of 22 per cent. ; but stands 

 over 20 years of age did not suffer much. On grassy soils the 

 cultures suffered considerably more than on open soil, even in 

 sandy situations. As regards mixed stands, spruce in the Harz 

 Mountains suffered more in the mixed than in pure stands, 

 especially in the deciduous mixture. Spruce with oak suffered 

 more than with beech, the lower stem classes particularly. When 

 mixed in single individuals the loss was less than when in groups. 

 Evidently the shallow-rooted spruce could secure less moisture 

 from the soil than the deeper-rooted deciduous' trees. In mixed 

 stands of pine with beech and oak no difference appeared, when 

 compared with pure stands. 



The resistance to drought of different species was found on 

 the whole to depend upon the depth of root system. The series 

 being beech, pine, oak, alder, birch and aspen, spruce. In cul- 

 tures, however, the series is somewhat different, namely oak, 

 spruce, pine, birch and alder. 



As regards the influence of depth of soil, even the young stands 

 suffered less on deep soil than on the shallower soils. As re- 

 gards exposure, apparently not much difference was found, the 

 loss on the plateau being 5 per cent., north and south exposures 

 9 per cent., south and west exposures 8 per cent. As regards 

 site classes, the better the more resistant were the stands shown 

 to be. As regards age classes, naturally the younger stands 

 showed the largest loss, the 1-20 age class showing a loss of 8^ 

 per cent., the age classes from 21 to 80 years between one and i.i 

 to i^ per cent., the older age classes showing a slight fraction. 



As a consequence of the larger amount of dead material, insect 

 pests began to develop rapidly, but the immediate utilization of 

 the dead material and pulling out of the young damaged growth, 

 and other thorough methods of combating the pests have prevented 



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