40 



PLAT 5. THE ROBINSON LAWN. 



This test was made on the lawn of Mr. R. H. Robinson in the 

 city of Geneva, which represented well the average lawn surrounding 

 a city residence. The turf, composed of Kentucky blue grass and 

 some red top, was quite badly infested with dandelions. This lawn 

 was sprayed four times during the season of 1915. A barrel sprayer 

 mounted on wheels and equipped with a long lead of hose was used, 

 and the solution was made by dissolving one and one-half pounds 

 of iron sulfate in each gallon of water. 



The results of the treatment were very similar to those obtained 

 on the Station grounds. The early blossoming of the dandelions 

 was prevented, and nearly all of the dandelions were killed. The 

 grasses suffered no permanent injury. 



One application of the solution was made July 31 when the soil 

 was quite dry. Following this spraying there was quite serious 

 blackening and scorching of the grass in certain spots where the soil 

 was dry and the solution applied in liberal quantities. This experi- 

 ence agrees with a previous one on the Station lawn in which it was 

 clearly demonstrated that lawns should not be sprayed during the 

 dry summer months when both the grass and the soil lacked moisture. 

 Also, some care should be exercised to prevent drenching of the grass 

 since injury to the crowns of the plants may result. 



At the end of the season, this lawn showed approximately three 

 per ct. of the original number of dandelion plants, and none had 

 blossomed or formed seeds. This season's test was considered to 

 be successful. 



THE EXPERIMENTS IN 1918. 



PLAT 1. 



This strip of lawn, five years after spraying, had no appearance 

 of any kind which would aid in determining its location. Some 

 white clover and yellow trefoil had reappeared in the plat, and it was 

 well infested with dandelions. There were as many dandelions in 

 this plat as in the adjoining lawns; but it is safe to say that they were 

 younger plants, the leaves being smaller, more nearly erect, and in 

 more compact clusters. 



PLATS 2 AND 3. 



These plats were in no particular to be distinguished from adjoin- 

 ing lawns. Apparently, they contained as many dandelions. Plants 



