MARYLAND WEATHER SERVICE 281 



Comandra umbellata 



Hypo. vis lii rs n I n 

 Habenaria ciliaris 

 Cypripedium acaule 

 Dicksonia punctilobula 

 J uncus dichotomies 

 Polygala viridescens 

 Eynchospora glomerata. 



Rocky Slopes. 



The Rocky Slope type of forest occurs throughout the Mountain 

 Zone in tracts of limited size. It has been examined in its virgin 

 state at Boiling Spring and Swallow Falls. It formerly existed 

 along the banks of the Youghiogheny, Castleman and Savage rivers 

 and in isolated groves at the heads of smaller tributary streams. 

 The dominant tree is the Hemlock, which forms 75% to 90% of tin' 

 stand. The circumstances under which the lumbering of the orginal 

 tracts took place has rendered the conditions extremely unfavorable 

 fur the reseeding of Hemlock, and the writer does not recall having 

 seen any second growth forest of this type. The principal deciduous 

 species in the forest are Yellow Birch, Red Maple and Sugar Maple. 

 Relatively infrequent are the Beech, the White Oak, the Butter-nut, 

 the Linden and the Yellow Birch. 



In some parts of the Rocky Slope forests, particularly along 

 streams, the undergrowth of Rhododendron maximum forms dense 

 thickets which are very difficult to penetrate, in other places the 

 floor of the forest is almost clear of shrubs and carpeted by small 

 herbaceous plants, mosses and hepatics. In addition to Rhododen- 

 dron, Kahnia latifolia is abundant. Viburnum alnifohum. a striking 

 shrub with large leaves resembling those of the Linden, is frequent 

 in these forests but not found elsewhere in the state. Sambucus 

 pubens is also frequent, ami in pockets of deep soil the prostrate 

 shrub Taxus minor is not uncommon, resembling the Hemlock very 

 strongly in the appearance of its foliage. Less frequent arc Men- 

 ziesia pilosa, Diervilla diervilla and Lonicera ciliata. 



