Rosendahl: observations on betula 445 



in Minnesota, efforts were made to secure staminate catkins and 

 young twigs and also if possible to find more stations for the species. 

 Several additional bushes were located, scattered throughout the 

 tamarack swamp in which the shrub was found the previous season. 

 Among these was one which differed from all the others in a very- 

 noticeable wintergreen flavor of the inner bark of the twigs and 

 young branches, in which character it agreed with Betula lutea. 

 The habit of the shrub, the small staminate catkins, and the appear- 

 ance of the unfolding leaves, as far as it was possible to judge, re- 

 sembled Betula Sandbergi somewhat closely. The unmistakable 

 wintergreen flavor of the inner bark, however, aroused suspicion, 

 and so the shrub was marked with the object of obtaining mature 

 fruits and leaves later in the season. Two collections were made 

 during the summer, one on July 11 and the other on September 22. 

 From the July collection it was very clear that the shrub was not 

 B. Sandbergi, for the catkins and bracts were even then much larger 

 than the corresponding structures in mature specimens of the latter. 

 Moreover, both bracts and nutlets were of a different shape and ap- 

 proached more closely those of B. lutea. That the shrub might be 

 a depauperate individual of B. lutea suggested itself, but the size, 

 form, serration and texture of the mature leaves at once precluded 

 this possibility. Apparently, therefore, another unrecognized shrubby 

 birch had been discovered. 



Before venturing to describe it as a new species, however, 

 further search in the field in the same general region, as well as in 

 other localities in the eastern part of the state, was continued for two 

 seasons. It seemed that if the plant merited specific recognition 

 there ought to be more than a single individual found in a region 

 w^iere much collecting has been done. Summer before last another 

 shrub of the same type was found in the vicinity of the first collec- 

 tion, and still another was discovered in one of the adjoining coun- 

 ties in a swamp about twenty-five miles towards the northeast. 



A study of the catkins, bracts, nutlets and leaves of both Betula 

 Sandbergi and the undescribed form revealed the interesting fact 

 that the former occupies a place intermediate between Betula papy- 

 rifera and B. piimila or rather B. puinila var. glandulifera, (which 

 is the form of the low birch which abounds in Alinnesota), while 

 the latter appears to be intermediate between Betula lutea and B. 

 pumila var. glandulifera. It was therefore natural to conclude that 



