29 



published a second paper * on the subject, in which he character- 

 izes the supposed annual habit of clover dodder as one of those 

 errors which, even in the realm of science, are sometimes held to 

 with remarkable tenacity. After citing his observations made in 

 1868, he states that he has since confirmed them in various years, 

 even in those having the hardest winters. 



With the exception of two recent articles f by the writers of 

 this paper, there seems to be no published record of any dodder 

 living over winter in the United States. Yet, our observations 

 indicate that Cuscuta Epithymiun is frequently perennial here.| 

 During the past three years this species has lived over winter in 

 New York alfalfa fields, hibernating on the crowns of alfalfa, red 

 clover, and certain weeds. This is not accidental or occasional, 

 but of common occurrence. In the writers' opinion, it is the chief 

 method by which dodder is carried over from one year to the next 

 in New York alfalfa fields. In dodder-infested fields live dodder 

 may be found readily during the winter and spring at any time 

 when the ground is free from snow. One should take a sharp, 

 heavy hoe or light grub-hoe and cut off and examine the crowns 

 of plants standing on the margin of a dodder spot of the previous 

 season. For the most part, the hibernating dodder threads 

 appear in the form of tufts of short, stout yellow threads, one 

 fourth to one half inch long, attached to the bases of the branches 

 close down to the ground around the crown of the host plant 

 and especially on the under sides of branches lying close to the 

 ground. Yellow, haustoria-bearing threads tightly coiled around 

 the very lowest parts of the stem are also common, but in no case 

 have we observed dodder on the root proper. 



Besides alfalfa and red clover, the favorite winter hosts of 

 dodder are fleabane [Erigeron animus) and yellow trefoil {^Medi- 

 cago hipulina). We have seen it also on dandelion. Although 



* Ber. Physiol. Lab. u. Vers. Anst. Landw. Inst. Halle. 1900. Heft 14, 



144-155- 



f (i) Stewart, F. C. Further studies on alfalfa dodder and trefoil. N. Y. State 

 Dept. Agr. Report of Director of Farmers' Institutes and Normal Institutes for the 

 year 1906, 67, 1907. (2) Stewart, F. C. et. al. Troubles of alfalfa in New York. 

 N. Y. Exp. Sta. Bull. 305. Nov., 1908. 



j Full details of these observations are given in N. Y. Exp. Sta. Bui. 305 : 369- 

 374- 



