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the same number from a charcoal bed weighed 40 grams. These 

 beds contained a relatively large quantity of charcoal, such as 

 could only be used in hotbeds, gardens, or other intensive work. 

 But the same tendency is shown in the use of smaller quantities. 

 Furthermore, the soil conditions are exceptionally bad in this 

 nursery. 



From constant observation and experiment, the action of char- 

 coal that makes it so valuable in the nursery seems to be entirely 

 in the improved conditions of moisture and warmth. It might be 

 thought that charcoal would loosen the soil to the extent that it 

 would dry easily if used in large quantities, but the opposite con- 

 dition occurs. In dry periods the powder of the soil to retain 

 water is increased, and in wet seasons the soil drains quickly with 

 a consequent prevention of fungus that always follows a wet 

 season in a coniferous nursery. The clay beds, by reason of their 

 caking habit in dry weather, and poor drainage in wet weather, 

 exerted the opposite efifects and the loss was much more marked. 

 In some cases it was complete. Again, charcoal beds are much 

 warmer, because of the darker color imparted to the soil. This 

 is of the greatest importance in the spring, when the ground has 

 a tendency to be cold. Germination is almost entirely dependent 

 on the warmth present and is consequently greatly helped by the 

 darker color of the soil. Since the darker colored soil does not 

 radiate any more rapidly at night, this heating effect is carried 

 forward into the night and lessens the liability of damage from 

 frost. In gardens and hotbeds, this is of considerable import- 

 ance. This increased heat is of value in another direction. The 

 aeration of the soil depends upon the heating, and it will be 

 greater in the soil which becomes warmer during the day. 



Thus we find that the action of charcoal in the soil is exerted 

 along the lines where the most can be accomplished. The phys- 

 ical conditions of the soil are so improved that the air, heat and 

 moisture coming to the crop is regulated in the most advantageous 

 manner, and mechanical analyses of the sub-soil have shown that 

 the charcoal exerts a beneficial action at a considerable depth, 

 twelve to eighteen inches below the surface. The sub-soil be- 

 neath charcoal beds is of a better color and better physical struc- 

 ture than soil from the surface of untreated beds. This means 

 an increase in the water-holding power, and a breaking up of 

 unavailable compounds into available plant food. 



To the farmer especially, the use of charcoal extends a wide 

 range of advantages. He can add to the value of his manure, 

 can improve the sanitary condition of the barnyard, poultry 

 house, hog pen, etc. ; and at the same time improve the physical 

 condition of his land. When used in larger quantities in gar- 

 dens, nursery beds, and in intensive cultivation, it offers the best 

 physical condition for the growing crop with a decrease of loss 

 from fungal attacks. The action of charcoal is comparatively 

 permanent as compared with the other agents, which are used 



