Sandy Bottomland

Description

Submodel

Description

The Mixed-grass/Mixed-brush Community (2.1) supports a 20 to 35 percent woody plant cover dominated by various bottomland hardwoods, although their numbers are often diminished. Mixed-brush areas form within the grassland particularly on recent sand deposits. Grassland vegetation still dominates herbage production. Midgrasses, shortgrasses and a variety of forbs dominate the herbaceous layer. All, but the more palatable woody species, have increased in size and density. The typical woody plant cover is dominated by mesquite, willow baccharis, salt cedar, ephedra and greenbriar. Pecan, cottonwood, western soapberry, hackberry and elm persist near the stream edge. Little bluestem often remains the dominant grass, but as regression progresses under heavy grazing pressure, it gives way to sand dropseed, silver bluestem, red lovegrass, and other less palatable shortgrasses and forbs. Alkali sacaton is abundant where saline soil conditions occur. Salt cedar may also invade these areas. Eastern redcedar is a common invader in the northern portion of this site. Annual herbage production ranges from 1,800 to 5,800 pounds per acre.

The Mixed-brush/Mixed-grass/Annuals Community (2.2) is composed of brush species including cottonwood, pecan, hackberry and western soapberry. Mesquite, willow baccharis and salt cedar have increased tremendously in the past few decades. The shrubs often form dense thickets where grazing has been heavy and continuous and fires have been excluded. Salt cedar and baccharis are particularly problematic where salinity has increased. Common understory shrubs are elbowbush, bumelia, plum and pricklyash. Midgrasses, shortgrasses, cool-season grasses and low quality annual and perennial forbs occupy the tree interspaces. Alkali sacaton, inland saltgrass and seep muhly become the primary grasses in deteriorated salty areas. The woody overstory can reach 75 percent ground cover with less than 25 percent of the herbage being produced by the grassland component.

Submodel

Description

This site, due to flooding and sandy soil is not recommended for cultivation. However, some sites in the past were farmed and planted to crops or planted to permanent pasture. Some are maintained in orchards. The permanent pasture could include bermudagrass, old world bluestems or other perennial plants.

Even though a Sandy Bottomland site may have been cultivated for a substantial period of time, the site can return to something resembling the reference state. The return of a cultivated field to the reference state depends on the soil integrity. Many things affect soil integrity, such as the amount of A horizon remaining, erosion, loss of organic matter, soil type, and others. There are many examples of idled cultivated fields that closely resemble the reference state. Remnant terraces usually reveal the fact that the fields were cultivated at some time in the past although terraces are not as common on bottomlands. It is sometimes difficult to determine if fields were cultivated others were not if successfully reseeded. The most obvious clue is the lack of native forb diversity.

If the cultivated land is abandoned, woody plants and early successional herbaceous herbaceous plants will establish. Without brush management, prescribed grazing or prescribed fires, the plant community will revert back to the Mixed brush/Mixed grass/Annuals Community (2.2)

Annual Production by Plant Type Table:
The plant production in the Converted Land is highly variable. If planted to permanent pasture and not fertilized, production will resemble the reference state. If fertilized, the plant community will produce more than the reference state depending upon level of fertility and rainfall. Total production and composition of an abandon land is very difficult to predict and should be determined on-site.