60 EXPEEIMENT STATION. [Jan. 



conditions. We have employed extensively the Weedicide man- 

 ufactured by the Bowker Fertilizer Company, with excellent 

 results. 



Some other experiments were made on some plots composed 

 of sand and gravel containing growths of Panicum sanguinale, 

 Panicum crus-galli, Poa annua, chickweed, dandelion, pepper 

 grass, Poman wormwood, pursley, sorrel and pigeon grass. 

 These plots were treated with formalin, salt, crude potash, 

 benzine, gasoline, carbolic acid and arsenate and arsenite of 

 soda, with similar results to those already mentioned. The ar- 

 senate and arsenite of soda destroyed all plants quickly and 

 with quite permanent effect, while the other compounds were 

 more or less effective for the foliage, but failed to be of value 

 in preventing new growths. Carbolic acid, as before, gave the 

 quickest results, and formalin in the proportion of 4 to 400 

 proved to be superior to salt. 



The following results were obtained from several treatments 

 of a driveway more or less troubled with a variety of weeds. 



Parts of the driveway were treated respectively with white 

 arsenic and sal soda, commercial sodium arsenate, carbolic 

 acid and lead nitrate, in the proportion of 1 to 20 and at the 

 rate of 10 gallons per square rod. The latter solution proved 

 to be of little value, and while carbolic acid destroyed the weeds, 

 a new crop appeared shortly afterward. The arsenate and ar- 

 senite of soda were both very effective. 



Numerous comparisons of the arsenate of soda and arsenite 

 of soda, made by dissolving white arsenic with equal parts or 

 more of sal soda in water, seemed to favor the latter somewhat. 

 The driveway referred to had been treated with arsenic com- 

 ])ounds about four times in ten years, and the absence of weeds 

 is quite noticeable. Where the wash in the highway accumu- 

 lates on this drive a few weeds occasionally appear, and this 

 is also true of ditches along highways which have been treated. 

 It is noticeable in one case that a ditch put through a driveway 

 which had been treated for weeds grew up luxuriantly to weeds, 

 due to the fact that the bottom soil of the ditch was placed on 

 top in filling it in. We have observed that when walks and 

 di'ivoways have received a few treatments with arsenic com- 

 pounds, applied at the rate of 2 pounds to 10 gallons of water. 



