NOTES ON CONIFEROUS SEEDLINGS. 

 R. T. Guthrie '12. 



An experiment was made to determine whether coniferous 

 seedlings have distinctive specific or generic characteristics by 

 which they may be recognized. The seed of twenty-two spe- 

 cies representing nine genera were sown in sandy loam on a 

 greenhouse bench. Seedlings of sixteen species representing 

 seven genera were obtained. They were examined at the time 

 of the development of the primary leaves which follow the 

 cotyledons, no secondary or true foliage being formed within 

 four months after planting. Many of the characters which 

 were noted seem to be variable and cannot be used as a basis 

 of classification. Very little difference was found between a 

 number of species. 



The serrulate character of leaves cannot be determined 

 without the aid of a hand lens. The lens shows minute, color- 

 less, sometimes recurved projections scattered at intervals or 

 rather numerously along the edges of the leaf. The number of 

 cotyledons given is the range found in the seedlings grown in 

 this experiment. A more extended test would doubtless show a 

 greater range in several of the species in which the number is 

 variable. The cotyledons of pine and spruce are wedge-shaped 

 in cross-section, forming a sector of the circle formed by their 

 whole number. The length of stem and leaves probably varies 

 with the conditions under which the seedlings are grown ; namely, 

 soil, moisture, temperature, depth of planting, and character 

 of the seed. 



Very little detailed work seems to have been done in the 

 study of coniferous seedling characteristics. H. Marshall Ward 

 in "Trees," Vol. V, gives a seedling key that includes thirteen 

 coniferous species. Three of these, Pinus strobus, Juniperus 



