250 DISEASE IN PLANTS. 



throughout in adaptation to the conditions, and 

 simply carry out their functions on a smaller 

 scale. 



Dwarfing is frequently a consequence of the 

 lack of food materials, or of some particular 

 ingredient in the soil, and in such cases is a 

 diseased condition of some danger ; similar results 

 may ensue in soils containing the necessary 

 chemical elements, but in unavailable forms. 



Dwarfing may also be brought about by repeated 

 maiming, nipping off the buds, pruning, etc., as in 

 the miniature trees of the Japanese; and the case 

 of trees continually browsed down by cattle, or of 

 moor plants perennially dwarfed by cutting winds, 

 are further illustrations in the same category, as 

 are also those of certain alpine and moraine 

 plants, whose only chance of survival depends 

 on their adapting themselves to the repeated 

 prunings suffered by every young shoot which 

 rises into the cutting winds, since there is no 

 question of lack of food-materials in these 

 cases. 



The practice of the Japanese is to pinch out the 

 growing tips of the shoots wherever they wish to 

 prune back, and it is by the judicious use of this 

 heading in, and suitable pot-culture, that the 

 dwarfs are made, 6-20 inches high at from 30-80 

 years old. 



Dwarfing is often brought about by grafting on 

 a slow-growing stock, and this method is employed 

 in practice, as are also heading in, pruning of roots, 

 and confinement in pots. 



