TREES AND SHRUBS 169 



flowering trees. Both of these are represented 

 by several species, and the representatives of each 

 are subject to considerable variation. 



There are at least two distinct hybrid catalpas, 

 involving three species, and I have noted great 

 difference in the rapidity of growth of seedling 

 catalpas; also variation in color and abundance 

 of flowers, in length of seed pods, and in manner 

 of growth of the trees themselves, some being 

 much more upright than others, and I have ob- 

 served magnolia hybrids also, and have thought 

 it matter for surprise that there are not more of 

 them, for the trees are readily cross-fertilized. 

 Doubtless the fact that different species bloom 

 at different seasons largely accounts for the rela- 

 tive infrequency of natural crossing. 



There is an opportunitj^ to work with the 

 catalpa, and I could scarcely mention a plant that 

 seems to me to give better promise for experi- 

 ments in crossing and selection than the great 

 and varied familj^ of magnolias. 



If the seeds are planted while fresh, they 

 germinate readily. The seedlings are easily 

 raised — almost as easily as apples or pears. 



Among the magnolia seedlings now growing 

 on my grounds, there are some that will grow 

 three or four feet the first season, while others 

 grow only as many inches. Some have a branch- 



