Ecological site R119XY050OK

Tree	Not specified
Shrub	Not specified
Herbaceous	Not specified

Landforms	(1) Flood plain (2) Flood-plain step (3) Terrace
Flooding duration	Brief (2 to 7 days)
Flooding frequency	None to frequent
Ponding frequency	None
Elevation	197 – 1994 ft
Slope	0 – 3 %
Ponding depth	0 in
Water table depth	0 – 48 in
Aspect	Aspect is not a significant factor

Frost-free period (average)	190 days
Freeze-free period (average)	220 days
Precipitation total (average)	60 in

Surface texture	(1) Cobbly loam (2) Gravelly very fine sandy loam (3) Loam
Family particle size	(1) Loamy
Drainage class	Poorly drained to well drained
Permeability class	Moderately slow to moderately rapid
Soil depth	80 in
Surface fragment cover <=3"	0 – 7 %
Surface fragment cover >3"	0 – 7 %
Available water capacity (0-40in)	3.9 – 7.9 in
Calcium carbonate equivalent (0-40in)	Not specified
Electrical conductivity (0-40in)	Not specified
Sodium adsorption ratio (0-40in)	Not specified
Soil reaction (1:1 water) (0-40in)	5 – 6.2
Subsurface fragment volume <=3" (Depth not specified)	1 – 30 %
Subsurface fragment volume >3" (Depth not specified)	0 – 16 %

Ecological dynamics

Information contained in this section was adapted from Missouri ESD. The information presented is representative of very complex vegetation communities. Key indicator plants, animals and ecological processes are described to help inform land management decisions. Plant communities will differ across the MLRA because of the naturally occurring variability in weather, soils, and aspect. The Reference Plant Community is not necessarily the management goal. The species lists are representative and are not botanical descriptions of all species occurring, or potentially occurring, on this site. They are not intended to cover every situation or the full range of conditions, species, and responses for the site.

The reference community is characterized as a savanna unit dominated by big bluestem and a wide variety of prairie wildflowers while other species added to the mix of upland drainageway prairie species. Slightly higher areas within or at the edge of the ecological site supported a savanna with scattered pin oak and willow.

This ecological site occurs at the base of slopes below upland prairies and woodlands, or as high, isolated terraces surrounded by floodplain forest. The higher position and loamy soil texture created a better drainage situation. Consequently, the site is less wet than adjacent sites. These areas occasionally flooded.

Fire also played a key role in maintaining this ecological site, likely occurring at least once every 3 years. Fire removed dead plant litter and provided room for a lush growth of prairie vegetation. Fire also controlled woody species. During fire free intervals woody species would have increased in abundance and spread out onto the main prairie. Grazing by native large herbivores, such deer furthermore impacted these sites. Their activities altered the composition, fuel loads and structure of the vegetation, adding to the diversity of structure and composition.

These sites are very productive. Today, Loamy Bottomlands are nearly extirpated from the region as the former terrace prairies and savannas have been converted to intensive agriculture. Few quality remnants exist. While re-establishing prairie and savanna on converted agriculture sites is beneficial to wildlife, restoration to the reference state from agricultural land is a long term proposition with uncertain outcomes.

A State and Transition Diagram is depicted in Figure 1. Detailed descriptions of each state, transition, plant community, and pathway follow the model. This model is based on available experimental research, field observations, professional consensus, and interpretations. It is likely to change as knowledge increases.

State and transition model

Custom diagram

Standard diagram

Figure 6. R119XY050OK, Loamy Bottomland

Figure 7. R119XY050OK, Loamy Bottomland

More interactive model formats are also available. View Interactive Models

More interactive model formats are also available. View Interactive Models
Click on state and transition labels to scroll to the respective text

Ecosystem states

1. Reference

State 1
Reference

This state is native oak savanna dominated by big bluestem and a wide variety of prairie forbs. This state occurs on level to gently sloping soils. Willow occurred in small groves or as scattered individuals across the landscape.

Two phases can occur that will transition back and forth depending on fire frequencies. Longer fire free intervals will allow woody species to increase such as oaks, prairie willow, dogwoods and wild plum. When fire intervals shorten these woody species will decrease.

This state is very rare. Nearly all former reference states have been converted to cool season grassland and intensive agriculture cropland. Small acres remain in a fire suppressed woodland community.

Additional community tables

Rangeland health reference sheet

Interpreting Indicators of Rangeland Health is a qualitative assessment protocol used to determine ecosystem condition based on benchmark characteristics described in the Reference Sheet. A suite of 17 (or more) indicators are typically considered in an assessment. The ecological site(s) representative of an assessment location must be known prior to applying the protocol and must be verified based on soils and climate. Current plant community cannot be used to identify the ecological site.

Author(s)/participant(s)
Contact for lead author
Date
Approved by
Approval date
Composition (Indicators 10 and 12) based on	Annual Production

Indicators

Number and extent of rills:
Presence of water flow patterns:
Number and height of erosional pedestals or terracettes:
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
Number of gullies and erosion associated with gullies:
Extent of wind scoured, blowouts and/or depositional areas:
Amount of litter movement (describe size and distance expected to travel):
Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
Presence and thickness of compaction layer (usually none; describe soil profile features which may be mistaken for compaction on this site):
Functional/Structural Groups (list in order of descending dominance by above-ground annual-production or live foliar cover using symbols: >>, >, = to indicate much greater than, greater than, and equal to):

Dominant:

Sub-dominant:

Other:

Additional:
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
Average percent litter cover (%) and depth ( in):
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
Potential invasive (including noxious) species (native and non-native). List species which BOTH characterize degraded states and have the potential to become a dominant or co-dominant species on the ecological site if their future establishment and growth is not actively controlled by management interventions. Species that become dominant for only one to several years (e.g., short-term response to drought or wildfire) are not invasive plants. Note that unlike other indicators, we are describing what is NOT expected in the reference state for the ecological site:
Perennial plant reproductive capability:

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Ecological site R119XY050OK

Loamy Bottomland

Accessed: 08/19/2026

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General information

Figure 1. Mapped extent

MLRA notes

Classification relationships

Ecological site concept

Table 1. Dominant plant species

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Conservation Service