MARYLAND WEATHER SERVICE ^'IK', 



has been far too brief to allow the natural operation of succession 

 to bring the forest to a composition differing from that which existed 

 when the groves were first left undisturbed. The selection of the 

 most valuable trees for cutting, or the desire to leave particular 

 species for shade or other purposes, determined the composition of 

 the groves from which these old stands have grown. There are in- 

 deed no tracts of forest in the district in which the process of human 

 selection has not been going on, usually in very recent years, so 

 that the forest composition of to-day presents a bewildering variety, 

 out of which it is difficult, even by extended comparisons, to recon- 

 struct the composition of the original forests of the area. The com- 

 monest tree of the Lower Midland to-day is the Chestnut, but it is 

 altogether likely that its ability to send up suckers from stumps, 

 together with the very rapid growth of the suckers as compared with 

 the slow growth of oak seedlings, or even oak suckers, is responsible 

 for its predominance. In like manner the Yellow Locust has be- 

 come a frequent tree merely through its readiness of reproduction. 



In spite of these considerations the attempt was made to find what 

 combination of trees represents the make-up of the oldest stands of 

 the district at the present time, for the variety of the different tracts 

 may be but little greater than would have been found in separated 

 tracts of the virgin forest. In selecting areas for exact determina- 

 tions of composition it was not the oldest that were taken, but those 

 stands of trees from 30 to 60 years of age in which competition be- 

 tween the different species might be thought to have taken place to 

 at least some extent. 



Near Glenville, in Harford County, is a tract which has what 

 comes near being the average composition of all the tracts carefully 

 examined. In it the Chestnut is the predominant tree, the Hickories 

 and Oaks forming nearly all the remaining percentage, the Chestnut 

 Oak being absent. Its make-up is as follows: 



Chestnut 357<, 



White Oak 20% 



Mockernut Hickory 15% 



Black Oak 10% 



Pignut Hickory 10% 



Bitternut Hickorv 3% 



Black Walnut 3% 



Tulip Tree 2% 



Beech 1% 



Miscellaneous 1% 



