526 Forestry Quarterly 



ber of roots and condition of foliage. For example the number 

 of lateral root branches was 5, 143, 468 respectively for the 

 full-shade, half-shade, and no-shade conditions. 



The average green v^^eight of plants in the no-shade bed w^as 

 almost tv^^ice that of those grown in the half-shade and a little 

 less than four times that of those grown in the full-shade bed. 

 The dry matter grown in the no-shade bed was almost twice as 

 great as that grown in the half-shade bed, and six times more 

 than that grown in the full-shade bed. The average ash con- 

 tent in the plants in the no-shade bed was over five times as 

 much as that in plants of the full-shade bed, but the latter were 

 richer in the percentage of ash. 



The second bulletin under notice deals with the problem of 

 the influence of lath covers upon water-loss from the White pine 

 seedlings and of the relation which such water-loss bears to the 

 evaporation from porous cups, atmometers, of the Livingston 

 type. The observations were made during the first two weeks 

 of August in fifteen four-hour periods. Under the no-shade 

 condition the average transpiration from six pine seedlings was 

 compared with the evaporation from the atmometers. During the 

 fifteen periods the average water loss per plant from six seed- 

 lings was : no-shade, 8.89 cc. ; half-shade 3.42 cc. ; full-shade, 0.47 

 cc. At the same time, the evaporation from a black atmometer 

 was 141.67 cc, 98.83 cc. ; and 53.33 cc. respectively for the no- 

 shade, half-shade and full-shade conditions. The ratio of evapor- 

 ation to transpiration, or the evaporation-transpiration coeffici- 

 ent becomes .063, .035 and .0088 in the three conditions in the 

 order enumerated above. It was found that the effect of cover on 

 the plants was more marked than upon the instruments. 



At the close of the experiments the plants were removed from 

 the beds and the average dry weight of the seedlings in each 

 case determined. The relation of water-loss from one gram dry 

 weight of seedlings grown in the different beds to the water-loss 

 from the atmometer from the same bed was found to be: no- 

 shade 1.53, half-shade 1.64, full shade 1.62 in the case of the 

 black atmometer. Comparing this state of affairs in three-month- 

 old seedlings with that of two and three-year-old seedlings, the 

 authors find that per gram of dry weight, the former give off 

 much more water than the latter, and hence they conclude that the 



