462 SUBSTITUTE FOR EOOT-WATEEING. 



roots with water, when newly planted, is much insisted on; 

 and in the case of large plants, particularly evergreens, it is, 

 undoubtedly, an essential process, partly because it causes the 

 flagging and injured roots to be immediately surrounded by an 

 abundant supply of liquid food, which, if the operation be 

 skilfully performed (see Macnab's Treatise, pp. 24 and 35), will 

 not subsequently fail them ; and partly because it is the only 

 means we possess of embedding with certainty all the fibres in 

 soU. "When the earth is reduced to the state of puddle, it wUl 

 settle round the finest roots, and place them as nearly as 

 possible in the same condition, with regard to the soil, that 

 they were in before the plants were removed. But the opera- 

 tion of puddling is unnecessary to small plants, if removed at a 

 proper season of the year, especially to deciduous trees of all 

 kinds ; and it may be injurious. This was long ago stated by 

 Mr. Knight {Hort. Trans, iii. 159), who found by experience 

 that when trees are very much out of health, in consequence of 

 having become dry, excess of moisture to the roots is often 

 fatal. This appears to arise from the languid powers of the 

 plant being insufficient to enable it to decompose and assimi- 

 late the water rapidly introduced into its system through 

 wounds in its root, or by the hygrometrical force of that part ; 

 under such circumstances, water will dissolve the mucilaginous 

 and other matters intended for the support of the nascent buds, 

 which matters then putrefy, lose their nutritive quality, and 

 destroy the tissue. The substitute for root-watering contrived 

 by Mr. Knight in such cases was, to keep the plants in a situa- 

 tion shaded from the morning sun, and to moisten their bark 

 frequently ; by these means water is presented to them slowly 

 through the young cortical integument, which, partaking of the 

 nature of a leaf, slowly absorbs it, probably decomposes it, and 

 transmits it laterally through the liber into the alburnum, 

 where it finds itself in the ordinary channel of the ascending 

 sap, and thus enters the system of circulation. In this way 

 Mr. Knight succeeded in preserving American Apple-trees, 

 which reached him in the middle of AprU, in so bad a state 

 that they seemed " perfectly lifeless and dry," and "much better 

 fitted for fire-wood than for planting." 



