February. 1912 



THE CANADIAN HORTICULTURIST 



37 



Fumigating with Tobacco. — A Good Smoke 



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Stand free kerosene, and you are likely 

 to get some. Tobacco decoction, or, 

 better, nicotine, especially put up for 

 greenhouse work, will be found more 

 satisfactory. Hot water kills most in- 

 sects by contact and may be used to 

 advantage. Water at one hundred and 

 fifty degrees will kill many Insects, and 

 will not injure the plants, while cold 

 water sprayed on plants is found the 

 best preventive against red spider, and 

 is much used in every greenhouse. 



Bordeaux mixture, four-four-forty, is 

 effective for many kinds of fungi. It is 

 somewhat objectionable because of the 

 unsightly appearance which it gives the 

 plants. Where this is not a serious ob- 

 jection, however, bordeaux is a great aid 

 to the grower. 



FUMIGATION .. 



Fumigation has become the greatest 

 aid of the greenhouse man, hydrocyanic 

 acid gas is the most effective. It is a 

 powerful poison. The fumes of this gas 

 are fatal to all animal life. The gas is 

 produced by the action of sulphuric acid 

 upon cyanide of potassium in the pres- 

 ence of water. The formula used is one 

 ounce of cyanide, two ounces of sulphuric 

 acid and four ounces of water. Much 

 controversy has occurred concerning the 

 amount of space which this should be 

 u.sed in. Mui h depends upon the kind 

 of plants you have, and the length of 

 lime the house is under fumigation. 



Most of the commercial houses have 

 only one way of opening the ventilators 

 and that from the inside. Because of 

 this the houses are usually fumigated the 

 last thing at night and not opened until 

 llie next morning. Under such condi- 

 tions the same amount of cyanide cannot 

 be used as there would be with a shorter 

 fumigati(;n. Taking the ordinary house, 

 with an .-til-night ap£lication, one ounce 

 of cyanide to two thousand or twenty- 



five hundred cubic feet, is as much as we 

 dare recommend. This will hold white 

 fly in check, and will clear them out if 

 used a few times at intervals of a few 

 days. 



Cyanide can not be carelessly hand- 

 led. Men do handle it, however, with- 

 out the great amount of trouble which 

 it formerly gave. The first time that we 

 used it, the chemical was tied in a paper 

 bag ; a cord fastened to the top ; placed 

 over a pulley ; and bag and contents 

 lowered into the acid after we had gone 

 out and bolted and barred the door. At 

 present the jars are arranged containing 

 acid and water and the cyanide wrapped 

 in paper. The operator simply throws 

 the material in the jars and rapidly 

 walks out. 



For aphides fumigation with tobacco 

 is still the proper thing to do. The pois- 

 onous alkaloids found in tobacco are 

 fatal to these lice. The stems may be 

 obtained at any cigar factory. They 

 must not be too dry. What we want is 

 a dense smoke, and this is only obtain- 

 ed when the stems burn slowly. These 

 stem may be burned in many ways. Some 

 gardeners merely pile the required 

 amount upon the floor, and set fire to it 

 by means of shavings. We have found 

 a piece of old stove pipe, arranged as 

 per illustration, a very effective burner. 

 The frequency with which a house should 

 be smoked cannot be definitely stated. 

 Do it as often as you are obliged to. 

 Ne-ver allow aphides to get too great a 

 start. 



THE USE OF SULPHUR 



Sulphur is of the greatest service in 

 greenhouse work, especially for mildews. 

 When mixed with vi'ater or milk the ma- 

 larial is painted on the steam pipes. The 

 fumes of sulphur are thus constantly 

 given off. Other methods of evaporating 

 sulphur are in common use. A common 



pla.i is to put the sulphur in a pan and 

 .set it over an oil-stove, with the flame 

 turned low. 



Sterilization is not necessary in all 

 greenhouses, but is quite necessary if 

 you have a bad attack of nematode. These 

 eel worms, as they are commonly called, 

 are very minute. Seldom are they seen 

 with the naked eye. But their presence 

 is always manifest by the galls or tuber- 

 cules which occur on the roots of affect- 

 ed plants. They multiply with extreme 

 rapidity and give no end of trouble. 



A few tomato roots badly attacked 

 are here shown. 



Our common method of control is to 

 arrange three lines of tile with open 

 joints, through the bed, and by coup- 

 lings, these tiles are connected with the 

 steam pipes. The steam is turned on, 

 and the soil is cooked. This cooking for 

 twelve hours is usually sufficient. As 

 soon as cool the bed may be set, and 

 should give little trouble afterwards. 



We are undertaking a series of experi- 

 ments with formalin and carbon bi-sul- 



Tomato Roots Attacked by Nematode 



phide as a means of cleaning out ne- 

 matode. These materials are used for 

 insects attacking below ground, but we 

 have not sufficient data to come to any 

 conclusion. 



Coal ashes while not containing any 

 real fertilizing ingredients, will greatly 

 improve the texture of a heavy soil, mak- 

 ing it lighter and warmer. Coal ashes 

 will act in the opposite way on a light, 

 sandy soil, by consolidating it and mak- 

 ing it more able to retain moisture. 



We start the first tomato plants about 

 March first, and we like to pinch them 

 out often. As soon as they have four 

 leaves on we pinch them out again. You 

 get a better looking plant by firming the 

 soil. We transplant three times- -often 

 four. We leaf them in shallow flats. 

 Spark's Earliana is grown for the ma- 

 jority. Chalk's Early Jewel is a fine look- 

 ing tomato, but two weeks late with us.^ — 

 J. L. Hilburn, Leamington, Ont. 



Here in the west I find it necessary to 

 start nearly all annuals in shallow boxes 

 in a hot bed under glass, which can be 

 done very easily if not attempted too 

 early in the spring.— D. W. Marden, 

 Pilot Mound, Man. 



