THE PEACH. 115 



serious disease to which this tree is subject. 

 Careful microscopic observations have shown 

 that in all cases of diseased trees different forms 

 of fungous growth enter first on the surface of 

 the trunk or branches, and penetrate throughout 

 the woody tissues. The tree becomes of a sickly- 

 yellow color, the foliage is much reduced in 

 size, the fruit ripens prematurely, and is insipid 

 in flavor. The debatable question is, whether 

 these fungi are the cause of disease, or only a 

 consequence of the enfeebled condition of the 

 tree. Working upon the last supposition, ex- 

 periments have been tried at the Massachusetts 

 Agricultural College to impart vigor to the tree, 

 by a liberal supply of the deficient element of 

 potash. It is stated by Professor Goessmann 

 that clironic cases of " yellows " have been re- 

 covered, after a treatment of three or four 

 years, hy the use of muriate of potash applied 

 to the roots. It certainly appears to be prob- 

 able that in this case, as is generally supposed 

 to be true in cases of Avhite mildews upon the 

 grape and gooseberry', the parasitic fungous 

 growth is invited by some enfeebled condition 

 of the plant. Instances of recovery, lyider 

 treatment, plainly point in this direction. 



If, instead of either of the formulas given 

 above as complete fertilizers, muriate of potasli 



