Charcoal in Nurseries 29 



mentioned. The preventatives which are given as being effective 

 seem to be too expensive for use in a nursery where the desire 

 is to raise fewer seedhngs to the bed, to work for stockiness, 

 in order that the seedHng may be fitted for permanent transplant- 

 ing at the end of two years. It is believed that five to six thou- 

 sand strong plants taken from 100 square feet ought to be the 

 aim, rather than twelve to fifteen thousand for transplanting 

 Since the first cost of the bed is the same under the two methods, 

 there must be a saving effected in the care of the less dense bed 

 during the two-year period. There seems to be good basis for a 

 belief that the application of charcoal to the bed is a very great 

 aid in the prevention of ''damping-off." Certain phases of the 

 subject are not as yet settled and experimentation will have to 

 continue longer before a definite statement to this effect can be 

 made. There were 3-50 beds sown in the Mont Alto Nursery this 

 year, White pine leading with 250, Norway spruce being sown on 

 50, and larch, Scotch pine, and Pitch pine occupying a small 

 number each. Constant observation of these beds seems to indi- 

 cate that where the proportion of charcoal in the bed is large there 

 is less "damping-off." In the section with 97 charcoal beds, only 

 six showed severe loss. The germination in these beds was so 

 delayed that the loss of 30 per cent, during the season was not 

 surprising. When the loss from weeding and other causes is 

 subtracted, not a very large proportion remains to be assigned to 

 the fungi. In another section in which ten beds were made almost 

 wholly of charcoal, there has been no loss at all from "damping- 

 off" and the beds are far too dense. In the clay beds adjoining 

 these, the loss was very great during the period from the twentieth 

 of June, in which rain fell thirteen out of twenty-six days. 



No exact percentage can be given as the proportion of charcoal 

 in the beds. The plot was plowed and disk-harrowed ; then about 

 3 inches of charcoal was spread over the top. The paths were 

 shoveled into the beds, raising the beds about 4 inches above the 

 surface. The spading was not done very deeply, thus keeping the 

 charcoal in the upper portion. Contrary to expectation, these 

 beds did not dry out easily, even in the severe drought of the fall, 

 while they drained out rapidly after heavy rains. 



There are so many factors affecting the activity of the "damp- 

 ing-off" fungi that it is almost impossible to say that any one 



