RAISING SEED. 161 



five years, that a rod of land well burned and prepared 

 in the fall, will furnish as many good plants as double 

 the area burned at the usual time, in February or March. 

 This planter, however, had never used the canvas covers. 



The question has been frequently asked, why soils 

 unburned will not answer as well as burned soils. All 

 the good effects of burning have never been accounted 

 for. We do know, however, that soils well burned will 

 bring strong, healthy plants, and those unburned will 

 often produce yellow, small and sickly ones. One effect 

 of the fire is to destroy all the seeds of weeds and grass, 

 giving the entire land to whatever seeds are sown upon 

 it. A second effect is to render the soil more permeable 

 to the roots of the plants, and by increasing its absorp- 

 tive capacity, preserve the proper degree of warmth and 

 moisture. A third effect is the inducing of a more 

 thorough pulverization of the soil, rendering it more 

 friable, and increasing, as it were, the area of the feed- 

 ing ground of the roots, thus rendering more plant food 

 available. 



Another beneficial effect is produced by the pres- 

 ence of minute particles of charcoal, which, being black, 

 makes the bed warmer, and being a good condenser of 

 the gases within its pores, particularly of carbonic acid 

 gas (absorbing, as it does, 90 times its volume), it col- 

 lects a rich supply of food for the plants. And finally, 

 it is well known to chemists that burned clay, being 

 more porous, absorbs ammoniacal and other gases from 

 the soil and from the atmosphere more readily, and fixes 

 them for the use of plants. All clays, says Mr. Johnson, 

 contain sensible quantities of most of the mineral sub- 

 stances, potash, soda, lime, etc., which plants require 

 for their healthy growth. They are, however, in an 

 insoluble condition, which circumstance, united to the 

 stiffness of the clay, prevents the roots of plants from 

 readily taking them up. The chemical condition of the 

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