PROTECTING FRUIT TREES. 307 



period. Gooseberry and Currant bushes may be pro- 

 tected by placing some straw over them in frosty weather 

 only. In all cases, do not fix the lower edge of the can- 

 vas nearer than i8in. from the ground. 



Protecting Orchard Trees. In America fruit growers 

 have long adopted a method of protecting orchard tree 

 blossoms from injury by frost by means of "smudge" 

 fires. The idea has been practised in England also with 

 good results. A special form of heater is used for the 

 purpose, and about fifty of them are required per acre, 

 placed at even distances apart. The apparatus has to be 

 charged with a handful of cotton waste saturated with 

 petroleum oil, then one of firewood, and finally some coal. 

 A cover has then to be placed on top. When frost is 

 imminent, the contents of the heater are ignited by means 

 of a torch of wire and cotton-waste saturated with oil. 

 The smoke from the consuming fuel is then emitted in a 

 steady, dense volume, completely enveloping the trees, 

 and effectually warding off the frost. The cost per acre 

 for keeping fires burning for one night is estimated at 

 2os. to 255. To guard against a sudden visita- 

 tion of frost, up-to-date growers have a thermometer 

 fixed up in an exposed place near the house, and this 

 connected with an electric alarm-bell situate in the bed- 

 room of the owner or his foreman. If the temperature 

 descends to freezing point, the bell is instantly set ringing, 

 and then is the time to light the heaters. Another method 

 is to start wood fires at intervals about 2oft. apart in the 

 plantation. In both cases the materials should always be 

 in readiness, and, needless to say, only employed when 

 there is a danger of severe frost setting in. Special 

 heaters are manufactured and sold in this country, the cost 

 of which would amount to at least 7 to 10 per acre, so 

 that " smudging " is after all rather an expensive method of 

 protecting fruit blossoms. 



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