173 



were secured at The New York Botanical Garden. Neither has 

 its pollen previously been used with success in any crosses unless 

 this was done at Strasbourg. 



And so the work of breeding day lilies resolved itself, first of 

 all, into a study of the sterilities, or we may say, of the physio- 

 logical incompatibilities (both self and cross) in the processes of 

 fertilization. It has been a case of trying to circumvent or over- 

 come the obstinate sterilities characteristic of these plants and 

 most particularly of the gaily-colored H. fulva. 



This work has been in progress for_ten_ xears. Thousands of 

 controlled pollinations have been made. Crosses which did not 

 succeed were repeated over and over until as in the H. flava and 

 H. fulva cross a few seedlings were obtained. A cross that failed 

 when made directly was sometimes made indirectly, so to speak, 

 by using a third type as an intermediate parent. As a result the 

 gayer and somewhat bold colors of the orange day lily have been 

 both subdued and intensified in combination with shades of yel- 

 low, golden-yellow, and orange. This has also been done with 

 the red tint of Hemerocallis aurantiaca. A color pattern rather 

 closely resembling that of the commonly cultivated form of H. 

 falva has actually appeared in the flowers of certain hybrids 

 between species other than H. fulva. 



But certain crosses between species and varieties are easy to 

 make. Thus the yellow-flowered Hemerocallis flava and the H. 

 Thunbergii with lemon-yellow flowers readily hybridize with H. 

 aurantiaca. The variety luieola (itself a hybrid between H. 

 aurantiaca var. major and H. Thunbergii) readily hybridizes with 

 H. aurantiaca and the seedlings of this cross are among the finest 

 thus far obtained at The New York Botanical Garden. Of the 

 combinations just mentioned more than two hundred hybrids have 

 already bloomed. Hybrids between other species and varieties are 

 also blooming. A total of about 1,500 hybrids (all different seed- 

 lings) are being grown. 



The flowers of these hybrids taken collectively exhibit a wide 

 range of colors from light lemon-yellow (even lighter than the 

 old Thunbergii) to a very dark rich orange. Nearly all these 

 shades are to be seen both in clear uniform color and in combina- 

 tion with various degrees of the red seen in H. fulva and H. 

 aurantiaca. The red may be rather uniformly dispersed over the 



