166 



THE DISADVANTAGES OF DEEP PLANTING TREES. 



themselves off on the public as first rale 

 gardeners. This acts injuriously on the 

 prosperity of gardening in many ways. 

 One is, that with inconsiderate people, 

 theory is often underrated in its impor- 

 tance. This should not be. It ought to 

 be an established rule, that no person should 

 be deemed a first rate member of any pro- 

 fession, who is not able to tell why a thing 

 is to be done as well as how. He should, j 

 in other words, be master of the theory of 

 his profession as well as the practice. 

 This holds good in the simplest operation. 

 A scientific workman is worth two mere 

 laborers ; every one knows that. With 

 these views, it is necessary to consider 

 why trees should be shallow planted. 



It has not yet been placed beyond dis- 

 pute that vital action, or life in vegetable 

 organisms, is caused by electric agency. 

 Many modern physiologists incline to that 

 opinion. But so far as the principle has 

 been tested by mechanical contrivances, it 

 seems to be a failure. It is, however, cer- 

 tain that vegetable life derives an essential 

 stimulus from heat. A great — probably 

 the greatest — part of the heat necessary to 

 the existence of vegetable life, is derived 

 through the medium of the roots. Hence 

 arises the necessity, that no impediment 

 intervene to interrupt the relations natu- 

 rally existing between heat and the roots. 

 It is essential that the temperature of the 

 atmosphere should generally approximate 

 to the soil around the roots ; because the 

 evaporation of the juices of a plant through 

 the leaves, by a given degree of heat, the 

 same or nearly the same degree of heat 

 can only supply, through the roots. And if 

 the roots of plants, therefore, be in a colder 

 medium than the leaves, more matter will 

 be evaporated than the roots can supply ; 

 and if the roots are in the warmer medium, 

 more matter is received into the system 



than the leaves can digest. In either case, 

 death is the consequence. It is probable 

 the temperature of the earth and air never 

 coincide altogether ; one being sometimes 

 much warmer than the other, and some- 

 times the contrary. It seems to be an 

 established principle, that vegetation is 

 healthier the nearer these approximate. 

 There is a great difference in the tempera- 

 ture of the soil at different depths, near the 

 surface of the earth. Lindley has some- 

 where published a case, where a trial in 

 summer gave 61°, Fahrenheit, at 6 inches 

 below the surface ; and at 3 feet, 44°. The 

 nearer, then, the roots are to the surface, 

 the more equal will be the heat to the roots 

 and to the leaves. 



Even could these principles be inviolate 

 when deep planting is resorted to, it is 

 doubtful whether plants could long remain 

 healthy so. It is an error to suppose, as 

 many do, that the roots of plants feed only 

 on the soil. They feed also on the gases 

 floating in the atmosphere, through the de- 

 composition of organic beings. More es- 

 pecially do they feed on ammonia, from 

 which they probably derive the major part 

 of their nitrogen. The mechanical force 

 of the descending rain brings these sub- 

 stances to the surface, where they are 

 left to be absorbed by the roots in the 

 immediate vicinity. Roots which are far 

 beneath the surface can so receive no 

 benefit from these revivifying circumstan- 

 ces. 



It follows, from these principles, that the 

 nearer the roots of plants are to the surface 

 of the earth, consistently with their real 

 known aversion to light, the nearer will 

 they be to those conditions which nature's 

 immutable laws declare to be most condu- 

 cive to a perfect state of health. Should 

 the transplanted tree be likely to suffer 

 from drouth, a good mulching will effectu* 



