320 MISCELLANEOUS FARM SUBJECTS 



Florida Sumatra wrapper tobacco ; the sandy loam is good for cotton, 

 sugar cane and corn. 



Houston Series. This occurs principally in the black, cal- 

 careous prairie regions of Alabama, Mississippi, and Texas. The 

 soils are characterized by a large percentage of lime, especially in the 

 subsoil, which in some of the types consists of white, chalky lime- 

 stone. The series has been derived from the weathering of calcareous 

 clays, chalk beds, and rotten limestones, all of late Cretaceous age. 

 In some localities remnants of later sandy and gravelly deposits have 

 been mingled with the calcareous material, giving rise to the gravelly 

 and loam members of the series. 



The soils of the Houston series constitute the fertile black prai- 

 ries of the Gulf States, and are not found east of Alabama. They are 

 without question the most productive upland soils of the Gulf Coastal 

 Plain, a fact mainly due to their calcareous nature. The Houston 

 black clay, locally known as black waxy land, is the most extensively 

 developed soil of the series. In the sections where it occurs it is the 

 best cotton soil. In the past it has been used chiefly in the produc- 

 tion of this crop, but, being well adapted to alfalfa, in recent years 

 the acreage in this legume has steadily increased. In its virgin state 

 it supported a heavy growth of native prairie grasses and in some 

 sections hay and pasturage are still its important products. The 

 Houston clay, while not as valuable land as the black clay, has a 

 special adaptation for alfalfa, and produces good yields of cotton and 

 the other staple crops. In the vicinity of San Antonio, Tex., there 

 is associated with the Houston black clay a black clay loam soil that 

 is good cotton, corn, and sorghum land, and which, under irrigation, 

 could be profitably used for some truck crops. 



Laredo Series. This consists of gray to light-brown calcareous 

 soils with gray calcareous subsoils. They occur as a terrace along 

 streams in south Texas and also constitute the principal soils of the 

 Rio Grande delta above overflow. They are made up largely of ma- 

 terial which has been brought down from the calcareous and more 

 arid parts of the State. They are seldom or never overflowed, and 

 constitute very valuable farming lands when irrigated. 



Laredo Silty Clay Loam. This is a very productive soil and 

 well adapted to growing early vegetables. Profitable yields of corn, 

 cotton, and sugar cane are obtained. Fair yields of both cotton and 

 corn are often secured in a favorable season without irrigation. Let- 

 tuce, melons, cauliflower, beets, peas, cabbage, onions, eggplant, cu- 

 cumbers, tomatoes, carrots, and both sweet and Irish potatoes are all 

 profitably grown under irrigation. Cabbage is the principal crop and 

 the average yield is about 18,000 pounds per acre ; the average yield 

 of onions is about the same. Irish potatoes yield from 60 to 70 bush- 

 els and sugar cane 25 to 30 tons per acre. The clay loam, also recog- 

 nized in the Laredo area, is well adapted to the production of onions, 

 giving an average yield of about 20,000 pounds per acre. Alfalfa has 

 been grown under irrigation, though the stand continues good for 

 only one year. Cabbage, beets, and Irish potatoes do well. Sorghum, 

 cowpeas, and sweet potatoes give good returns. The Laredo silty clay 



