2,0 FRUITS AND VEGETABLES UNDER GLASS 



more rapidly in cloudy weatlicr than when it is clear. I am inclined to at- 

 tribute it to poor root action, or cold, imperl'ect drainage, or lack of free ven- 

 tilation, each of which, singly or combined, will bring on this dreaded disease. 

 I will not attempt to give anj- remedy or cure for it; the best suggestion I can 

 make is, to give all the fresh air possible and have the foliage dry over night. 

 When badly infected, it is not worth while to waste any time over the plants, 

 but just pull them up and start afresh. Here, again, the grower must make 

 preparations for a clean start, or the trouble will be likely to reappear with the 

 new crop. 



When this fungus once gets into the beds, measures must be taken to eradi- 

 cate it. A grower with the necessary equipment, or having a steam plant instead 

 of the hot water system, can sterilize the soil and thus kill all the fungous growth, 

 Have a series of perforated pipes buried in the beds and attached to the steam 

 system. Let the holes be about one foot apart, and of a size in accordance with 

 the steam pressure. Cover the bed with some close mateual, as canvas, before 

 beginning to steam it. Place enough pipes in the soil to heat it up to near 200°. 

 Establishments not equipped with steam must adopt other methods. In a 

 bad case of infection remove about an inch of the surface soil and replace it 

 with fresh soil, adding a light coat of air-slaked lime. But with a compost 

 that is free and open, which induces free root action, there should be little cause 

 for disease. 



Another thing to guard against is the destruction caused by aphis. Lettuce 

 will absolutely refuse to grow when infested with green fly. Various methods 

 may be adopted to fight this insect. The very best plan is, not to wait until 

 the plants get infested, but to take precautionary measures at the right time. 

 There are several good fumigating materials that are excellent for destroying 

 insect life. Any one of these used in a mild form before the fly appears is de- 

 cidedly better than waitii.g until it is there. There is nothing so efTecti\e in 

 eradicating insect life as hydrocyanic gas. If this is used once or twice while 

 the Lettuce is still young, or before it begins to head, there will be no trouble 

 with lly afterward, for it certainly makes clean work with the fly, without 

 harm to the growing crop. Hydrocyanic acid gas is one of the most simple 

 remedies, and, abo\c all, one of the most economical. It is death to the fly, 

 even in a very mild form. In using it, however, we must remember that we are 

 dealing with a deadly poison, and it should be treated as such at all times; but 

 there is absolutely no danger when it is handled carefully. A close house is 

 necessary; the gas will escape if there is any outlet, either above or below grade. 

 If there is an\ hole where the pipes enter the house, as is often the case, this 

 should be iilled up with leaves or anything else that will hold back the gas. 

 The cyanide of potassium can be purchased of different strengths, up to ()8%. 

 The kind I have always used is 50 fuse or $0% pure, using one-half ounce 

 to every 1000 cubic feet of space. Earthenware receptacles must be used; 

 two will be sufTicient for a house fifty feet by twenty feet. Place them at an 

 equal distance apart, and have the jars considerably larger than necessary to 

 hold the material. Gallon jars are not any too large. The operation seems so 

 simple and withal so clfectix e, that it is strange that this gas is not more generally 



