Missouri Department of Conservation

Taxonomy

Common Name: WEAK RUSH

Phylum: MAGNOLIOPHYTA

Class: LILIOPSIDA

Order: JUNCALES

Family: JUNCACEAE

Genus: JUNCUS

Species: DEBILIS

Taxonomic Authority: A. GRAY

Taxonomy References: 002 , 003 , 005

Status

STATE RANK S1
GLOBAL RANK G5

Status References: 001

Habitat Summary

"Is found as an emergent to mostly submerged aquatic in streams; elsewhere in a variety of moist, sandy habitats, also creeks, ponds, and seepages (on dolomitic substrate)."

Primary Habitat: "Aquatic - river/stream"

References: 002 , 003

Distribution

General Occurrence in State:

"Known only from Ripley and Jefferson counties *02,03,04*."

County Occurance

County Occurence
Known Likely Unknown Not Likely Historic Extirpated
JEFFERSON SHANNON
RIPLEY ST. LOUIS

References for distribution: 002 , 003 , 004

Distribution by Watersheds

Big R.
Current R.

Comments: "Historic record: 11010011 (Eleven Point R.) *04*."

Distribution by Ecoregions

Comments: ""

Distribution by Potential Natural Vegetation

Oak-Hickory Forest
Oak-Hickory-Pine Forest

Distribution by Natural Divisions of Missouri

Ozark Border: Mississippi River
Ozark: Lower Ozark

Habitat Associations

Species is associated with "Aquatic" habitats.

National Wetlands Inventory Association:

Palustrine
Riverine

Aquatic Associations:

"Palustrine", "Emergent, persistent",
"Riverine, unknown perennial"

References for Aquatic Associations: 002 , 003

Habitat Types:

References for Habitat Types:

Terrestrial Natural Communities:

Streambed

References for Terrestrial Natural Communities: 002 , 003

Food Habits

Trophic Level:

""

Larval Food Habits

Comments for larval food habits:
""

References for larval food habits:

Juvenile Food Habits

Comments for Juvenile Food Habits:
""

References Juvenile Food Habits

Adult Food Habits

Comments for Adult Food Habits:
""

References Adult Food Habits

Niche Requirements

Egg Niche Requirements

References for egg niches requirements:

Feeding Larvae Niche Requirements

References for feeding larvae niche requirements:

Resting Larvae Niche Requirements

References for resting Larvae niche requirements:

Feeding Juvenile Niche Requirements

References for feeding juvenile niche requirements:

Resting Juvenile Niche Requirements

References for resting juvenile niche requirements:

Breeding Adult Niche Requirements

References for feeding Adult niche requirements:

Feeding Adult Niche Requirements

References for feeding adult niche requirements:

Resting Adult Niche Requirements

References for resting adult niche requirements:

Niche Requirement Summary

General habitat association specified in comments(00270)

Comments about Life History:

Code Comment
042 Occasionally roots at the nodes where aerial stems have become horizontal and in contact with the substrate, presumably following flooding *002*.

Life History Information

Reproduction (plants):plants monoecious
Reproduction (plants):see comments(042)
Duration of plant:perennial
Life form:herb
Flowering period begins: June
Flowering period ends: August
Origin in state: native

Comments about Life History:

Code Comment
042 Occasionally roots at the nodes where aerial stems have become horizontal and in contact with the substrate, presumably following flooding *002*.

References for life history: 002

Management

Beneficial Management Practices:

Beneficial Management References:

Adverse Managment Practices:

Adverse Management References:

Comments on Management:

References for Management Comments:

References

Reference Code Citation
001 Missouri Natural Heritage Program. 2004. Missouri Species and Communities of Conservation Concern Checklist. Missouri Department Of Conservation. Jefferson City, Missouri. 47 Pp.
002 Yatskievych, G. 1999. Steyermark's Flora Of Missouri. Vol.1 Jefferson City, Missouri. Department Of Conservation. 991 Pp.
003 Unpb Flora Of Missouri Database. G. Yatskievych, Missouri Botanical Garden, P.O. Box 299, St. Louis, Mo. 63166-0299. 314-577-9522.
004 Unpb Missouri Department Of Conservation Heritage Database. P.O. Box 180, Jefferson City, Missouri 65102. 573-751-4115.
005 Usda, Nrcs. 2001 The Plants Database, Version 3.1 (Http://Plants>Usda>Gov). National Plant Data Center, Baton Rouge, La 70874-4490 Usa.