FUNGUS DISEASES. 105 



additional precaution sometimes employed is to 

 grow the plants in pans or small boxes and water 

 them only by setting these in a tank of water of 

 nearly the same depth, allowing the water to soak 

 into the soil, but not touch the plants. The disease 

 is seldom troublesome on plants grown thinly in 

 the open air. If it makes its appearance, water 

 thoroughly, but not too often, and sprinkle dry 

 sand over the seed-bed among the plants.* 



Black Leg or Mildew. — This is a disease which 

 attacks the stems of young plants which are 

 being wintered over. It is undoubtedly due to one 

 or more species of parasitic fungi, but I do not find 

 that the subject has been studied. Doubtless the 

 rux^ture of the bark by alternate freezing and 

 thawing gives the fungi an opportunity to attack 

 the plant. The disease is prevented and kept in 

 check by keeping the seed-bed dry. An occasional 

 dressing of sand, lime, wood- ashes or rubbish of 

 any kind, is useful. 



* A series of articles upon " damping off " may be 

 found in the American Garden for 1889, pp. 3i7-9. 



