MARYLAND WEATHER SERVICE 163 



siderable variety is seen in their vegetation. The most extensive 

 tract which was visited is the celebrated Zekiah swamp in Charles 

 County, which occupies the valley of the Wicomico Kiver for a dis- 

 tance of fully ten miles, and has a width of one-half to one mile. 

 At its southern end it merges into a fresh marsh, as may be seen 

 at Allen Fresh. At some seasons of the year the swamp is largely 

 flooded, but at the time visited (July 1st and 10th) it might be 

 considered a low-lying forest traversed by several branches of the 

 Kiver. Owing to its frequent inundation the soil is a soft rich 

 alluvial material, and the arborescent covering is so dense that not 

 only is the soil constantly moist, but herbaceous vegetation is sparse. 

 On the fallen trunks grow a great variety of mosses and slime- 

 moulds, as well as fleshy fungi. The composition of the forest 

 varies somewhat in different parts, probably owing to relative mois- 

 ture. In one section, near the junction of Clark Run, with the main 

 stream, where the level is only moderately low (in fact part has 

 at one time been under cultivation), the dominant tree is Sweet 

 Gum, associated with much Black Gum, Red Maple, Willow Oak, 

 Swamp Oak, Beech, Holly, and other species in smaller numbers. 

 Half a mile farther north the leading species is the River Birch, 

 while Sweet Gum, Willow Oak, the Hornbeam, and Holly take sec- 

 ond rank. A more extended examination was made of the region 

 at the point where the county bridge crosses the swamp. Here the 

 general level is low, with standing water in many places. Many 

 large trees are to be seen here, left, no doubt, because of the great 

 difficulty in getting out timber. These are generally Swamp Oak, 

 although other species are common as e. g., Hornbeam, Sweet Gum, 

 staple, Birch, Black Gum and Holly; while Ash, Elm, Willow Oak, 

 Black Oak, Overcup Oak and Paw Paw are less common. Along 

 the water courses Alders, Willows, the Button Bush and the Winter- 

 berry are frequent, and on the road are specimens of Buttonwood, 

 a tree which is uncommon in the body of the swamp. 



Besides the Zekiah swamp there are others of smaller area in the 

 district, as along the Patuxent between Anne Arundel and Prince 

 George's counties. Here, as in the previous case, the dominant 

 trees are Sweet Gum, River Birch and Swamp Oak, but here, the 

 Buttonwood becomes more plentiful, and the Box-elder is a con- 



