APPLE DISEASES 149 



ROSETTE 

 Caused by adverse soil conditions 



This peculiar condition attracted attention in Colorado apple 

 orchards following the severe winters of 1898 and 1899. In 1901 

 it was particularly noticeable in several orchards of one locality 

 in that state. What may prove to be the same trouble has 

 subsequently been observed in California and Idaho. Records 

 of apple-rosette have not come from any other sources, so that 

 the disease seems to be limited in its geographical range. This 

 fact alone accounts for the disease being considered as one of the 

 minor troubles of the apple. 



Symptoms. 



The rosette of apple is said to present an appearance sugges- 

 tive of peach-rosette. The characteristic feature of the disease 

 is the presence of a tuft or rosette of small leaves at the ends of 

 branches; such "branches are otherwise nearly destitute of 

 foliage. Affected limbs and even whole trees die from the effects 

 of rosette. In the spring the lateral buds die, and the terminal 

 one develops a clustered branch on which the leaves are much 

 more dense than they normally should be; whence the term 

 rosette. 



Cause. 



Apple-rosette is called a soil disease. No parasites of any 

 kind are concerned. Like most diseases of this sort the true 

 cause will probably remain in obscurity for some time to come. 

 Conditions accompanying the disease are somewhat as follows : 

 in an excess of marl and an adverse water-supply the tree sends 

 out few or no fibrous roots. In fact the roots cannot penetrate 

 this type of soil to any extent, consequently the tree has a 

 shallow root-system, and the water-supply becomes inadequate. 

 Accompanying these provoking conditions is winter-injury, 

 which comes about in the following way : the water may be in 

 sufficient quantities in the early part of the season, but by the 



