42 



seedling plant could be found. However, in the greater part of 

 this lawn area, sprayed four times with the power sprayer, there were 

 as many dandelions as in adjoining unsprayed lawns. But it should 

 be stated that the dandelions in the sprayed area were mainly young 

 seedling plants. 



PLAT 5. THE ROBINSON LAWN. 



The owner of this lawn decided to spray, in 1919, only restricted 

 areas on which the dandelions blossomed. It was unnecessary to 

 spray the entire lawn. This lawn, being in fairly good condition at 

 the outset of the test, responded well to the treatment by filling in 

 the bare places with a growth of grass. It is believed by the writer 

 that heavy reseeding would have been advantageous in this instance, 

 and would have hastened the thickening of the stand of grass. The 

 behavior of this lawn, bordered on both sides by lawns producing 

 dandelion seeds, seemed to demonstrate that, on the average lawn 

 similarly situated, three or four sprayings during the season with 

 iron sulfate applied carefully and at the proper time will practically 

 control the dandelion pest for a period of from two to three years. 



OTHER METHODS OF ERADICATION COMPARED WITH 



SPRAYING. 



CUTTING. 



Plainly, the problem of eradicating dandelions by cutting them 

 out involves the question of the large amount of reserve food stored 

 up in the root of the plant; also the fact that dandelion roots, when 

 cut, callous over and produce a varying number of adventitious buds 

 upon the upper end portion of the cut crown of the root. 



As early as 1873, Caspary, followed by Warming in 1877 and by 

 Wittrock in 1884, demonstrated that the dandelion (Taraxacum 

 offidnale) and certain other plants have the power to produce sprouts 

 from adventitious buds on their roots when they are cut. 



Hitchcock and Clothier (1898) and also Longyear (1918) have 

 fully demonstrated that pieces of dandelion roots even an inch long 

 may produce many new sprouts from adventitious buds on the cut 

 crowns. The former writers found as many as fourteen new sprouts 

 from a dandelion root cut off two inches below the surface of the soil. 



Munson (1903) concluded from his study of the behavior of plants 

 of two species of dandelions that, since every top or crown cut off 



