IO2 WEEDS OF THE FARM AND GARDEN 



in brass tanks. Use a hand sprayer for patches; in the 

 field a large sprayer with nozzle to spray a fine mist. 

 Spray in bright sunshiny weather, at least not to be fol- 

 lowed by rain for a few days. It is best to have the spray 

 followed by a dew. This is true in particular of the dust 

 spray. 



It should be remembered in this connection that spray- 

 ing cannot be done indiscriminately to all kinds of plants. 

 It will not do to spray a clover meadow, since the iron 

 sulphate is quite as injurious to the clover as to the 

 weeds, nor is it advisable to use the sprayer in a corn 

 field, because many of the common weeds, like the foxtail, 

 crab grass, and pigeon grass, cannot be killed by this 

 spray. But it is certain that the iron sulphate has a wide 

 application in grain fields. 



Mr. R. I. Anthony, who has had some experience in 

 spraying, notes some of the conditions which may cause 

 failure or success, as follows : 



"Spraying for the eradication of weeds started in 

 Europe in France and Germany. These two countries 

 possess a climate very different from anything I know 

 in this country. When the procedure was studied a set 

 of rules for guidance quickly found place and one of these 

 was that the spraying should be carried on only on 

 bright, still days. 



"In my work from time to time I have met with fail- 

 ure and have as often been puzzled to discover why. On 

 collating the work it is clearly evident that the weather 

 conditions play a great part. French weed in certain 

 stages of growth is completely destroyed by the sulphate 

 of iron spray when the day is overcast and the relative 

 humidity high. On the contrary, when the day is bright, 

 hot, and the humidity low, the plants are resistant. The 

 same is true of mustard in a less degree. 



"Work at Warren this year has so far been a failure, 

 with atmospheric conditions as follows : Bright skies, low 



