52 ROSES 



described in 1826. This is an old enemy, and 

 has long been known to the rose growers in 

 Europe. The foliage, when attacked, soon 

 develops the characteristic black spots, and 

 the leaves become elsewhere pale, and shortly 

 fall to the ground. As a result, rose houses 

 badly infested with the black spot show but 

 few leaves and fewer blooms. The micro- 

 scopic structure of this fungus has been fully 

 considered, with plates, in the first annual 

 report made by Professor Scribner as Chief 

 of the Section of Vegetable Pathology of the 

 United States Department of Agriculture, for 

 the year 1887. This trouble may be held in 

 check by the carbonate of copper compound, 

 using five ounces of the carbonate of copper 

 to three quarts of ammonia and sixty gallons 

 of water. The spraying should be done once 

 a week, using a hose with a nozzle that gives 

 a fine spray. The point should be to wet 

 every part of the plant, and yet not drench it. 

 If many leaves have fallen from the plant they 

 should be gathered up and burned. 



Some varieties are more liable to the black 

 spot than others. When possible that is, 

 when all other things remain the same it is, 

 of course, wise to grow those least susceptible 



