Sometime ago it was the prevailing idea that dynamite was un- 

 necessary for tree planting unless the soil chanced to be underlaid 

 with hardpan, in which case the explosive was regarded as valuable 

 for breaking up the hard soil. It has been found by experiment how- 

 ever, that trees thrive better when planted in blasted holes than in 

 hand-dug holes if there is underlying hardpan, or clay, clay loam or 

 silty loams that are liable to become hard or impervious. 



The explanation of this is simple. It is because the explosion of 

 the dynamite loosens up the soil for yards around the spot, and thus 

 makes root growth easy; whereas, digging the hole with tools tends 

 to pack the earth around the sides and at the bottom of the hole and 

 retard root growth. 



Scientific agriculturists have discovered that water is the most im- 

 portant element in all kinds of plant growth. It forms a major 

 portion of the green weight of the roots, trunk, branches, twigs, leaves 

 and fruit of the plant. The proportion of moisture will, of course, 

 vary in the different parts. The roots will be found to contain more 

 moisture than the trunk, and the branches, twigs and fruit a larger 

 percentage than the hard wood parts. 



Water or soil moisture is the carrier of the tree's plant food. It 

 also influences the temperature of the plant. In dry hot weather the 

 evaporation of large amounts of water from the leaves of a tree has a 

 slightly refrigerating action. It requires more heat units to raise a 

 given weight of water one degree in temperature than it requires to 

 cause a similar increase in the same weight of wood or stone. This is 

 effective in saving trees from immediate harm due to quick changes 

 of temperature. Moisture also has the effect of maintaining the stiff- 

 ness of the more succulent parts of the plant. A good illustration 

 of this is the noticeable withering of corn and other plant leaves when 

 the supply of moisture is insufficient. Lack of moisture is just as 

 effective in retarding the development of leaves of trees, but it is not 

 so noticeable. Soil which is of the natural consistency to allow water 

 to circulate freely through it and still retain or conserve it so that it is 

 available at all times for growing plants, may be considered as ideal 

 for agricultural purposes. Few soils possess this natural consistency. 

 Other soils, which may be classified as good, average, or fair, must 

 have artificial preparation in order to make them produce the results 

 that may be expected from the rarely-found perfect natural soil. 



Few persons understand the principle of plant growth. It is not 

 necessary, as many suppose, that the root of a plant shall come in actual 

 contact with all of the plant food elements of the soil needed for the 

 sustenance of the plant or tree. Plant roots have the power to draw 

 from the surrounding soil the necessary elements of plant food, pro- 

 vided the soil is of such a character as to permit the passage of these 

 elements through it. Water or moisture is the carrier of these plant- 

 food elements through the soil and into the plant roots. This will 

 indicate the importance of a porous soil which will permit the free 

 passage of water through it in order that plants growing upon the 

 surface may be properly nurtured for rapid and healthy growth. 



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