1S70.] CULTIVATION OF HARDY FRUITS. 351 



is intended to bear the crop. In the smaller-growing varieties, 4 to 6 

 inches, and in the larger kinds 9 or 10 inches, will be found to be a 

 good distance for the crop. To the half of these distances let them at 

 this stage be thinned, and when thoroughly stoned the superfluous 

 fruit may be removed. 



The principal diseases with which the Apricot is attacked in this 

 country are gum, canker, mildew, and that mysterious dying-off of the 

 branches, and sometimes whole limbs, during the growing season. The 

 exudation of gum is generally, though not perhaps always, the result 

 of some external injury. Undue twisting or bending of branches, to 

 the breaking of the bark or injury of the cellular tissue, is in every 

 case followed at an earlier or later date, according to the extent of the 

 damage, by an exudation of gum. Sometimes, at the nailing season, 

 by a slip of the hand of the operator, the hammer may fall upon a 

 branch and injure the bark ; this also is the precursor of this disease. 

 There is no known remedy for it, so that every care and precaution 

 ought to be exercised to avoid the slightest injury to the tree 

 which might lead to this result. Canker in the case of the 

 Apricot, as in everything else, is the result of the tree being 

 planted in an uncongenial soil, or when the roots penetrate down 

 into a bad subsoil. Whenever the first symptoms of it appear, 

 means ought to be adopted to prevent its further progress, and to re- 

 establish the constitution of the tree. To accomplish this, the tree 

 ought to be well root -pruned, having all rank and watery roots 

 removed ; after which a good supply of fresh soil ought, if possible, 

 to be procured, into which the tree may be planted : this will for 

 a time, at all events, stop the further progress of the disease. " Mil- 

 dew appears," Mr Knight has stated (see ' Horticultural Transactions,' 

 vol. i. p. 86) " to be the want of a sufficient supply of moisture 

 from the soil, with the excess of humidity in the air, particularly 

 if the plants be exposed to a temperature below that to which they 

 have been accustomed." This appears to be a fair statement of the 

 case ; and so far as my own experience has gone, it was only under 

 such circumstances that I have seen mildew attack the iVpricot. The 

 best remedy is an application of sulphur upon the first appearance 

 of an attack. The cause of the dying-off of portions of a tree at 

 the growing period is involved in considerable mystery. Various 

 are the reasons given by many of our best horticulturists regarding 

 the matter ; but most of these opinions are mere speculations, and 

 by them only given as such. Some have said that it is the result 

 of sunstroke, others that it is through injury sustained by the sap- 

 vessels through the agency of frost. I am rather sceptical regard- 

 ing either of these being the cause, as I have noticed that branches 



