126 Forestry Quarterly. 



more' evident as they grow older. Contrary to the fears of many, 

 at the age of 20 years, the great density has not produced stands 

 with thin weak stems, but not only high but thick stems with 

 strong crowns have been differentiated. 



The spreading habit should not only be considered in spacing 

 plantations, but also in the practice of thinnings, in which the 

 advantages of the density must be considered and its disadvan- 

 tages avoided. 



He inveighs against both too early (10 year) and late thin- 

 nings (30 to 40 year), the latter delaying too long the decision 

 of what is to be dominant. In a vigorously growing stand he 

 proposes to thin at an age of 15 years and the thinnings cannot 

 be repeated too often, if possible annually during the years 15 

 to 20. In that manner a dominant stand of well distributed trees 

 and a lower story of soil cover can be developed, taking out only 

 what is of damage to neighbors and leaving the oppressed harm- 

 less part. 



A rather unconvincing experiment with such a thinning method 

 closes the otherwise suggestive article. 



Zur Variation des Wachstums bei unseren Waldbdumen, etc. Forst- 

 wissenschaftliches Centralblatt. November, 1910. Pp. 565-578. 



Bohmerle whose observations on the influ- 



Moss Cover ence of moss cover on natural regeneration 



and we briefed in Vol. VII, p. 200, now brings 



Increment. data from the Austrian forest experiment 



station showing the influence of moss cover 



on increment of pine in the same forest near Vienna which is 



characterized by a dry climate, especially during the period of 



vegetation. 



The forest is described in the previous brief. 

 The inimical influence had been remarked in the previous 

 publication but additional experiments were instituted in two 

 plats, in which on one-half the area the moss cover was care- 

 fully lifted and turned over, so that without scarifying the soil 

 the living moss cover was changed into a dead one, and the 

 vegetative activity of the moss and its use of water for the same 

 was destroyed. 



This was done in 1907. In 1908 a decided drouthy year oc- 

 curred, but 1909 and 1910 were rainy years. 



