ON CHRYSANTHEMUMS. 



165 



this be not done the teleutospores are dispersed in various 

 ways, many faUing upon the soil. They will not germinate the 

 same season, but they assuredly will do so in the ensuing spring, 

 commencing again the cycle of life, unless the grower sprays 

 his plants from the earliest times, as suggested below. 



There is absolutely no cure when once the Leaf-Rust fungus 

 has asserted itself. It is, however, possible to stay its progress 

 by spraying with sulphide of potassium (a common fungicide 

 with rosarians and others), at the rate of loz. to 3galls. of water, 

 used lukewarm. This will destroy the spores before they can 

 enter the foliage. Affected plants should also be isolated. As a 

 precautionary measure, too, growers would be well advised to 

 spray periodically — say, every eight or ten days — throughout the 

 season. Still, notwithstanding the spraying, some of the spores 

 will doubtless find a suitable resting-place. Where, therefore, the 

 disease has been knowm to exist, very great care should be 

 exercised by the gardener in collecting every leaf and stem from 

 plants which have been infested, and instead of consigning them 

 to the rubbish-heap they should be burned, otherwise next season 

 the chances are that a severer attack will be experienced. 



Mildew^ though not a formidable fungus disease like the 

 one just described, is nevertheless undesirable, and has a 

 debilitating effect upon its host-plant. Many growers are under 

 the impression that certain atmospheric conditions are able to 

 produce Mildew : in other w^ords, that a spontaneous origin is 

 possible. Those, however, who have paid a little attention will 

 know that while certain conditions will predispose to an attack, 

 the Mildew usually found upon Chrysanthemums is due to the 

 presence of a specific fungus, Oidiu??t chrysajifhe??ii, a relative of 

 that pest of the Vine, Oidium Tuckeri. Powdered sulphur, or 

 better still, spraying with sulphide of potassium of the strength 

 recommended for Leaf-Rust, will be found effectual, especially if 

 combined with plenty of light and air, and fluctuations of 

 temperature are avoided. 



Leaf-Spot (^Septoria chrysanthemi) is a disfiguring and weakening 

 fungus disease characterised by dark brown spots on the foliage. 

 They are at first small, but gradually increase in size, and the 

 leaves fall. Spraying, as before recommended, is the remedy. 



Damping. — The condition of the blossoms popularly described 

 as " damping " is too well know^n. Frequently it is present with 

 the Mildew attack above noted, the conditions of the atmosphere 

 being favourable for the development of either. Chrysanthe- 

 mums in foggy towms are more liable to the condition than those 

 grow^n where fogs are comparatively light. An atmosphere sur- 

 charged with moisture is also fatal, and therefore a buoyant one 

 should prevail. Another prolific source of "damping" is due 

 to the use, or rather to the abuse, of stimulants. 



