PAPERS OX BIOLOGY AND AGRICULTURE 16o 



the shrubs are to be found almost without exception on 

 the higher and dryer banks. 



ExceiDtions to the suggestion contained in this paper 

 undoubtedly occur. In three cases in Illinois, small 

 plantings of escaped shrubs occur where it is not known 

 that primeval forest has existed. In one instance, the 

 shrubs grew beneath cultivated cedars of considerable 

 age, and in the remaining two instances where fences 

 had sei*ved as resting places for birds. These shrubs, 

 however, were not of any great age and may be supposed 

 to be the only remaining j^lants from himdreds of seeds 

 similarly dropped throughout many square miles of land 

 never forested; hence truly adventitious in that habitat. 



BESUME 



The habitat of naturalized barberry shiiibs in the cold- 

 temperate belt of the United States has been suggested 

 as influenced by the presence or absence of calcareous 

 soils. It is shown in the present paper that in Illinois 

 an apparent relation between heath and ''timber-soils'* 

 and barberry occurrence exists so generally as to indi- 

 cate that this shrub, in becoming naturalized, seeks a 

 characteristic shrub habitat. A practical application of 

 this fact lies in paying particular attention to those 

 districts characterized as having "timber soils", in the 

 search for naturalized plantings of the common bar- 

 berry, 



BIBLIOGRAPHY 



1. DeCandolle. Alph. 



Geographie botanique. 2: 746-747. 1855. 



2. LyelL Charles 



A second visit to the United States. 1: 32. 

 .3. Bierelow. J. 



Florula Bostoniensis. (1st ed.) 7S. 1S14. 



4. Kerner and Oliver 



The natiiral history of plants. Half vol. IV: S64. 1S95. 



5. McAtee. W. L. 



How to attract birds in the east central states. U. S. D. A. 

 Farmers' Bui. 912. 



6. Rhind. W. 



A history of the vegetable kingdom. 1857. 



7. Kern, F. D. 



Observations on the dissemination of the barberry. Ecol- 

 ogy 2: 211-214. 1921. 



8. Kern. F. D. 



Distribution of Berberis vulaari^ in Pennsylvania. Bui. Tor. 

 Bot. Club 4S: 263-269. 



