72 ESTABLISHMENT OF A NATIONAL BOTANIC GARDEN. 



The Soils of the Proposed Botanic Garden Site on Anacostia 



Kiver, D. C. 



[By Hugh H. Bennett, Bureau of Soils.] 



The tract of land included in the soil survey lies on the west side 

 of Anacostia River, between the Bladensburg Road and the river, 

 and between the Pennsylvania Railroad on the north and M Street 

 on the south. The topography ranges from level to rolling, with steep 

 slopes on Mount Hamilton, Hickey Hill, Licking Banks, and along 

 the deep ravines that have cut into the southeastern side of Mount 

 Hamilton and from the Anacostia marsh back into the uplands of 

 the northeastern part of the tract. The range of elevation is from 

 tide level to about 239 feet at the peak of Mount Hamilton. 



The boundaries between the several classes of soil shown on the 

 map were not traced out in detail in all cases, but they are sufficiently 

 accurate to show the essential soil features of the tract. Some unim- 

 portant small patches of soil have been ignored in this survey. 



The soils of the tract vary widely in the character of both the soil 

 and subsoil material, in depth of soil, and in topography and drain- 

 age. There is a range from good sandy loam soil of easy working 

 quality to the most intractable clay and stony sandy land of low 

 productivity. The principal upland soils consist of : (1) Sandy loam, 

 with stiff red clay subsoil, constituting a medium good grade of agri- 

 cultural land ; (2) sandy loam, with light reddish to red sandy clay sub- 

 soil, representing good agricultural land; (3) stiff red clay and clay 

 loam, partly steep and stony, representing land of low productivity; 

 (4) droughty sandy slopes and stony hilltop land of poor to fair agri- 

 cultural value. The stream bottoms are subject to overflow, and in 

 present condition are permanently wet, with the exception of the 

 relatively high flat (or low second bottom) area near the mouth of 

 the stream crossing the tract about its center, which is occupied bjr 

 good well-drained sandy loam and loam. The marshes include (1) 

 siltv clay of fairly firm consistency and (2) boggy material under- 

 lain by peat. 



The material forming the upland soils consists of water-laid or 

 marine sediments (Coastal Plain material). The sandstone rock 

 occurring on the hills and slopes was locally formed by cementation 

 of sand with iron oxide, apparently in the same manner some of the 

 more consolidated "hardpan" layers of the West are formed. Some 

 of the rock resembles bogiron ore. 



The soils represented on the tract are common to eastern and 

 southern Maryland, Delaware, and southern Xew Jersey- The better 

 grades of land represented here are extensively farmed through this 

 region, being used for vegetables, the general farm crops, tree fruits, 

 and berries. Commercial fertilizers are in common use and applica- 

 tions of lime are frequently made with good results. The soils are 

 deficient in humus and probably most of them are much in need of 

 lime. 



UPLAND SOILS. 



Soils "-/fJi stiff red clay subsoils — Susquehanna group. — These soils 

 have heavy, plastic, red-clay subsoils, which frequently are mottled 

 with gray, white, yellow, and shades of red. The sandy loam (24) 



