Natric Till Plain Savanna

Description

This state is a savanna community dominated by big bluestem, switchgrass, sedges and forbs, with an overstory of scattered oaks and hickories. This state occurs on level to gently sloping soils that have high sodium levels and a seasonal high water table during the spring months in most years. Some ponding may also occur. These conditions influence the species composition and site productivity. Two phases can occur that will transition back and forth depending on fire and wetness frequencies. This state is extremely rare (maybe completely expatriated). Nearly all sites have been converted to cool season grassland and cropland. Some altered sites have transitioned to woodland.

Dominant plant species

1. post oak (Quercus stellata), tree

2. Carolina rose (Rosa carolina), shrub

3. sedge (Carex), grass

4. switchgrass (Panicum virgatum), grass

Submodel

Description

These existing alternative areas have experienced fire exclusion for decades along with periodic uncontrolled domestic livestock grazing. In the absence of fire, ongoing recruitment of trees into the canopy develops a closed canopy, shading out the herbaceous ground flora. Oak, hickory and midstory species increase. Herbaceous cover and diversity greatly diminishes, leaf litter builds up, and more shade-tolerant species persist.

Dominant plant species

1. pin oak (Quercus palustris), tree

2. swamp white oak (Quercus bicolor), tree

3. red maple (Acer rubrum), tree

4. American elm (Ulmus americana), tree

5. goldenrod (Solidago), grass

Submodel

Description

Conversion of other states to non-native cool season species such as tall fescue (Schedonorus arundinaceus (Schreb.) Dumort., nom. cons.) and white clover (Trifolium repens L.) has occurred in the MLRA. A return to the reference state may be impossible, requiring a very long term series of management options.

Dominant plant species

1. tall fescue (Schedonorus arundinaceus), grass

2. creeping bentgrass (Agrostis stolonifera), grass

3. white clover (Trifolium repens), grass

Submodel

Description

This is the dominant state that exists currently with intensive cropping of corn (Zea mays L.), soybeans (Glycine max (L.) Merr.), and common wheat (Triticum aestivum L.) occurring. When weather turns dry, drought symptoms on crops often appear (Figure 3). Some conversion to cool season hay land occurs for a limited period of time before transitioning back to cropland.

Dominant plant species

1. corn (Zea mays), grass

2. common wheat (Triticum aestivum), grass

3. soybean (Glycine max), grass

Submodel