Comments: Overall, this species does not seem to be highly threatened at present, but there are definitely challenges to the persistence of some populations.
Wholesale destruction of wetlands by draining for agriculture and housing developments is a significant threat (Cusick pers. comm., Evans pers. comm., Smith pers. comm.). Populations have likely been destroyed through the years due to these activities. Due to the rapid urbanization of the Virginia coastal region, populations may be destroyed through habitat destruction, water quality degradation, and boat-wake disturbances (Ludwig pers. comm.).
Dredging of stream and rivers, coupled with the drainage of upland wetlands, has quickened the run-off of spring melt-waters and rainfall. Excessive run-off over a shortened period of time has likely had detrimental effects on historic C. decomposita populations by increasing the height of flood waters and affecting new habitats. Apparently, the species is not able to survive in areas where water levels fluctuate significantly throughout the year (Bryson per. comm.); it is only found in old oxbow swamps away from the current flooding regime, sinkhole ponds and other wetlands of this sort. Natural upland cover and wetlands within the watersheds should be restored and/or protected.
Conversion of natural ponds to stock watering holes through the deepening and removal of native vegetation is also a significant threat to the species (Smith pers. comm.). Other natural ponds may experience degradation due to grazing during periods of prolonged drought.
Logging of habitat has also apparently been a threat to C. decomposita. Evans (pers. comm.) stated that populations in western Kentucky have undoubtedly been destroyed in the past due to drainage and clearing of the extensive wetlands in that part of the state.
The log sedge is apparently only found in areas that are not subjected to herbicide use (Bryson pers. comm.). In areas adjacent to rice fields, herbicide (2-4-D or 2-4-5-T) use has eliminated the species (Bryson pers. comm.).
Road grading of populations located on roadbanks within swamps is a threat to such populations in Illinois (Schwegman pers. comm.). Shifting ice sometimes takes out dead snags and the plants associated with them (Schwegman pers. comm.).
In at least Arkansas, water hyacinth is becoming a serious issue; at least two Arkansas sites are impacted.