378 PROCEEDINGS OF THE ACADEMY OF [Aug., 



or less completely covered with vegetation. All three kinds of marsh 

 may be covered at the time of the Spring and Fall tides, and they are 

 intersected by ditches, thorofares, and deeper boat channels, which 

 give a characteristic appearance to the monotonous landscape. 



The following analysis of a machine-cut sod, 10 x 10 x 27 inches, 

 weighing 121 pounds, was made by Dr. Jacob G. Lipman, of the New 

 Jersey Agricultural College, from material taken August 13, 1907, on 

 a Raritan marsh opposite Sayreville: 



Original Weight, 121 pounds. 



• Dry Weight, 23.39 " 



Moisture, 80.67 per cent. 



Dry Matter, 19.33 " 



Upper Portion. Lower Portion. 



Nitrogen, 0.65 per cent. 0.63 per cent. 



Organic Matter, . . .34.23 " 21.30 " 



Ash, 65.75 " 78.70 " 



The spongy, fibrous character of the upper portion of the sod, ex- 

 tending from twelve to eighteen inches and composed of roots and 

 other vegetable matter, is gradually modified in its lower portion. 

 The distinct root structure tends to disappear, and with the darker 

 color the entire mass becomes more compact and resembles muck 

 rather than peat. The proportionate amount of carbon and ash are 

 both increased, while the proportion of organic matter is diminished. 7 



The development of the salt marsh vegetation was studied in a 

 number of places. When the mud flats rise above the surface at any 

 stage of tide plants begin to invade them. Such a bar, uncovered 

 in the Shrewsbury River five or six years ago, according to a fisherman 

 who lived in the neighborhood, is now covered by a dense growth of 

 Spartina stricta maritima, a grass which has large root-stocks that ex- 

 tend deep into the mud. At the end of each year the tops of this wiry 

 grass die, and new shoots come up the next Spring; mud and other 

 materials are held at the base of the stems until the surface is gradually 

 built up, when the first type of salt marsh passes into the second. 

 -Gradually other plants come in that have a root system adapted to 

 growth under the conditions provided by mud covered and uncovered 

 alternately by tidal flow, until the zonal arrangement of plants which 



7 Smith, John B.: The New Jersey Salt Marsh and its Improvement, Bulletin 

 207, New Jersey Agricultural Experiment Station, 1907. In one marsh the writer 

 found the marsh soil above a gravel bed measured 82 cm. (= 32J inches), and 

 in a subsequent paper he will describe the appearance and constitution of 'each 

 soil stratum. 



