THE VEGETATION OF SHACKLEFORD BANK 



By I. F. Lewis. 



INTRODUCTION 



Shackleford Bank is the strip of land extending from Cape Lookout 

 on tlie east to Beaufort Inlet on tlie west. It is about eight miles long 

 and, on an average, half a mile broad. On the south it is bounded by 

 the Atlantic Ocean, on the north by Bogue Sound. Together with Core 

 Bank, with which it is continuous, it forms a long link in the chain of 

 sand reefs bordering the southeastern coast of the United States. 



GEOLOGY 



Evidence has recently been brought forward by Cobb^ to show that 

 this long sand reef is essentially a part of the mainland, and that the 

 adjoining sound may be regarded as the estuary of a river which was 

 formerly "a southern tributary of the large river made up of the Pam- 

 lico and the I^euse." 



SOILS 



The soils of Shackleford may be classified under three heads: (a) A 

 fine white marine sand, with little or no humus, is found on the outer 

 beach, the dunes, and in places bordering the sound, (h) A gray sandy 

 loam in the elevated central portion of the Bank. The quantity of 

 humus in the soil varies. In places it is slight in amount, but usually 

 it is present in sufficient quantities to form a good garden soil, capable 

 of supporting a luxuriant vegetation, (c) In the marshes on the sound 

 side of the bank a black mud, 1 to 2 feet deep, is found overlying a sandy 

 substratum. 



The soil water is usually 18 inches or less below the surface, and, 

 with the exception noted below, uniformly fresh. Even where the tides 

 cover the marshes, and water standing on the surface is salt, with a spe- 

 cific gravity of 1.023, the soil water is fresh. In this case the ground 

 water probably comes up from below through the sand, the soil being 

 too impervious to allow the surface salt water to ipercolate through to 

 the fresh water below. Only in the Spartina-Salicornia marshes, which 

 are constantly wet with salt water, is the ground water not fresh. Wher- 

 ever plants other than Spartina glabra (strida), Salicornia spp. or 

 Borrichia frutcsccns grow, the ground water is fresh. 



^Notes on the Geology of Core Bank, N. C. : Journal of the Elisha Mitchell Scientific Society, 

 Vol. 23, No. 1. 1907. 



