NOTES AND QUERIES. 



NOTES AND QUERIES. 



Moisture v. Light in the Development of Stands. 



In considering the relationship of individual trees to one 

 another in areas of forest growth, emphasis has always been 

 placed upon the importance of light as the determining factor in 

 the development of the crop. Recent articles by continental 

 officials are of much interest, and would indicate that the 

 amount of moisture which reaches the individual trees, may 

 possibly be as important. The matter is one which deserves 

 some attention. 



For example, one forester points out how the shape of the 

 twigs and branches of beech causes the rain-water which falls 

 upon them to run along definite channels on the tree itself, and 

 so down the trunk to the ground. In this way the tree practi- 

 cally monopolises the rainfall over the area which its crown 

 covers, and conducts the water to its own roots. Oak, on the 

 other hand, allows the rain-water to drop off from innumerable 

 small projections, so that the ground under its crown receives a 

 large amount of moisture. This, he thinks, may be the main 

 reason why the vegetation is so luxuriant under an oak wood 

 and practically absent under beech, and not the difference in 

 shade cast by the species. 



Another authority, dealing with the same subject, relates how 

 he isolated some suppressed trees in a wood, by digging a trench 

 round them, so that all the roots from the neighbouring stems 

 were cut. These suppressed trees, so isolated that there was no 

 competition for soil moisture, continued to live, while others, not 

 so treated, died off in the usual way. Further, within the 

 isolated area, quite a strong vegetation developed, although the 

 overhead light had not been increased. 



In a plantation of Abies grandis at Novar, it was quite 

 interesting to observe how the large, dominant stems appropriated 

 more of the rainfall than the suppressed and sub-dominant trees. 

 So much so, that after a light shower the stems of the first 

 were running with water in a few minutes, while the latter 

 remained quite dry below the crown. In this respect, this silver 

 fir resembles beech. A Douglas fir wood close by, on the other 

 hand, resembled oak, in that the rain-water dripped through its 



