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recommended for lawns badly infested with dandelions. Reseeding 

 of the lawn is advised as a supplementary measure. 



During 1914, Arthur reported that, in Indiana, on one area sprayed 

 with iron sulfate four times in 1913 and three times in 1914, most of 

 the dandelions were killed, but that they again appeared during the 

 next three months and later became quite abundant. On another 

 area, sprayed four times during 1914, approximately one-half of the 

 dandelions were killed. After-treatment measures, in the form of 

 liming the soil and reseeding with blue grass seed, were used in these 

 experiments. 



In a recent and very complete bulletin, Longyear (1918) discussed 

 the life.histqry of the dandelion and some methods of eradication used 

 in Colorado. This experimenter concludes that there is no easy, 

 certain method of exterminating the dandelion or of holding it in 

 check for any considerable length of time. However, it may be 

 kept under control by persistently employing one or more of the fol- 

 lowing methods: (a) careful establishment of the lawn and later 

 heavy reseeding; (b) applying a small amount of gasoline or kerosene 

 to the crown of each individual plant; (c) deep digging of the entire 

 plant; (d) prevention of seed production on the premises; and (e) 

 by spraying infested lawns with a solution of iron sulfate. The last- 

 named method, labor costs considered, proved to be the cheapest and 

 most effective method of eradicating dandelions. 



THE DANDELION. 



SPECIES. 



In New York lawns the common dandelion (Taraxacum officinale 

 Weber) with its showy flowers and ragged, mussy foliage is the one 

 generally found. However, the red -seeded dandelion (T. erythros- 

 permum Andrz.) occurs occasionally. The red-seeded dandelion is 

 readily distinguished from the common dandelion by its smaller, 

 sulphur-yellow heads, glaucous bracts, more finely cut leaves and 

 bright red or red-brown seeds with very fine grayish- white pappus. 

 The common dandelion has orange-yellow heads, coarsely pinnatifid 

 and bluntly lanceolate leaves, and olive-green or brownish seeds 

 with short .hard points. In both species, when the blossom appears, 

 the double row of bracts which encloses the many-flowered head 

 spreads apart and exposes them. The inner involucre closes after 



