44 



of the cut plants were dead. The other seven had made some 

 growth. By September 1 only four of the twenty plants were alive. 

 Apparently, the plants were killed at the outset by cutting them 

 during dry weather. These results do not agree with those obtained 

 in other tests on more favorable locations, and can be explained only 

 by the fact that the soil upon which the plants grew was exceedingly 

 dry, and the cutting was immediately followed by very dry weather. 

 (3) Cutting plants in midsummer, or later, caused new growth at 

 the expense of reserve food stored in the roots, and gave the best 

 results by either killing the plants or weakening them. 



CUTTING VS. SPRAYING DANDELIONS. 



At this station, French (1911) concluded from his experiments and 

 observation that spraying did not remove the leaves so completely 

 from treated plants as did cutting, since plants which survived six 

 or more cuttings could withstand as many sprayings and probably 

 more. In order to obtain further data on this point, three experi- 

 ments were conducted as follows : 



Experiment 1. Ten pairs of dandelion plants of practically the 

 same size, and growing within a foot of each other were selected. One 

 plant of each pair was cut off below the crown, while the other plant 

 was " sprayed off " with twenty per ct. iron sulfate solution. These 

 plants were cut off and " sprayed off " on the same date five times 

 during the season, the first treatment being given on May 3. Fol- 

 lowing each treatment, the " sprayed off " plants were the first to 

 respond by making new growth. These plants usually made a 

 growth of from three to five inches, and had four or five leaves before 

 the cut-off plants were large enough to be again cut off. At the 

 time of the third treatment, only one of the cut-off plants was alive, 

 while four plants of the " sprayed-off " series were living, two of them 

 having made a vigorous growth. At the time of the fourth treatment 

 only two plants in the " sprayed-off " series were living. The foliage 

 of these was again killed down by the sulfate solution. However, 

 on October 3 of that year one of these plants was still living, and 

 made some foliage which was " sprayed off " for the fifth time, after 

 which it did not reappear. This experiment showed that in every 

 case the " sprayed-off " plants were the last to succumb to the treat- 

 ment, this indicating, in this case at least, that cutting is more 

 effective than spraying. 



