1915] BROWN— PINUS STROBUS 



239 



15. White pine has long roots and short roots. Only the first 

 elongate to any extent and often are in s3Tnbiosis with mycorhiza. 

 Growth in length begins during the last half of April, in some cases 

 even earlier; no reUable data were obtained regarding its cessation. 

 Secondary growth occurs during the first season and proceeds 

 in the usual way. 



This work was undertaken at the suggestion of Professor W. W. 

 RowLEE, Cornell University, to whom I am very grateful for 

 help and criticism. Acknowledgments are also due to Professor 

 Walter Mulford and Professor John R. Bentley of the De- 

 partment of Forestry, New York State College of Agriculture, 

 Ithaca, N.Y. 



Syracuse University 

 Syracuse, N.Y. 



LITERATURE CITED 



1. Brown, H. P., Growth studies in forest trees, I. Pinus rigida Mill. 

 BoT. Gaz. 54:386-402. 1912. 



2. BucKHOUT, W. A., The formation of the annual ring of wood in the Euro- 

 pean larch and the white pine. Forest Quar. 5:259-267. 1907. 



3. BusGEN, M., Bau und Leben unserer Waldbaume. 1897. 



4. , Einiges iiber Gestalt und Wachstumweise der Baumwurzeln 



AUg. Forst- und Jagd-Zeit. 77:273-278, 73:305-309. 1901. 



5. Christison, H., Observations on the annual increase in girth of trees in the 

 Royal Botanic Garden and at CraighUl, near Edinburgh, from 1878 to 

 1887. Trans, and Proc. Bot. Soc, Part I, July 12, 1887; Part II, Feb. 14, 

 1889. 



6. Engler, a., Perioden in Wurzelwachstum. Promethes 16:623, 624. 1905. 



7. Friedrich, J., tjber den Einfluse der Witterung auf den Baumzuwachs. 

 Mitth. Forstl. Versuchs. Oesterr. 22:pp. 160. 1897. 



8. GoEF, E. S., The resumption of root growth in spring. Wis. Agric. Sta. 

 Ann. Rep. 15:220-228. 1898. 



9. Hartig, R., Das Holz der Deutschen Nadelwaldbaume. 1885. p. 35. 



10. , Ein Ringelungsversuch. Allg. Forst- und Jagd-Zeit. 1889. 



11. , Anatomie und Physiologic der Pflanzen. 1891. 



12. Hartig, T., Anatomie und Physiologic der Holzpflanzen. 1878. 



13. JoST, L., Betrachtungen iiber den zeitlichen Verlauf des sekundaren 

 Dichenwachstums der Baume. Ber. Deutsch. Bot. Gesells. 10:587-605. 

 1892. 



