Juncus bufonius

L. (1753)

This name is accepted

Kingdom: Viridiplantae Phylum: Magnoliophyta Class/Clade: Monocots Order: Poales Family: Juncaceae Genus: Juncus

common rush, toad rush

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Description

Key Characters:

Growth Form: Annual herbs.

Stems: Stems green, slender, terete (cylindrical), 0.5–4 dm long, usually tufted, branched from base.

Roots:

Leaves: Leaves simple. Leaves few per stem. Blades flat to subterete, 3–15 cm long, 1–1.5 mm wide. Margins entire. Sheaths with hyaline margins, not prolonged into auricles. Stipules absent.

Flowers: Flowers solitary, in upper ⅓–½ of plant, forming leafy, compound, dichasial cymes, lowest bract leaf-like, each flower subtended by 2 hyaline bracteoles, some flowers cleistogamous. Flowers bisexual (perfect), pale green. Outer perianth parts 4–7 mm long, apex acute to acuminate. Inner perianth shorter than outer ones, apex acute to subacute, sometimes emarginate and mucronate, all with hyaline margins. Stamens (3)6; anthers shorter than to longer than filaments. Pollen grains remaining in tetrads, surrounded by a common exine. Ovary superior, carpels 1.

Fruit: Capsules 3–celled; 3–5 mm long; apex and base acute to rarely truncate. Seeds brown; obliquely obovoid to ellipsoid– truncate; minutely reticulate; 0.3–0.5 mm long; without appendages.

Ploidy: 2n = 30 to 2n = 120

Habitat: Naturalized along roadsides and trails; in disturbed boggy sites and grasslands.

Elevation Range: 1,000–1,500 m.

Historical Distribution

Images

Synonyms (61)

Uses and Culture

USES

Natural History

Statewide Status

Naturalized

Island Status

Kaua'i Naturalized
O'ahu Naturalized
Molokai Naturalized
Maui Naturalized
Hawai'i Naturalized

Dispersal Agents


Pollinators

Bibliography

Name Published In: Sp. Pl.: 328 (1753)

Other References

Wagner et al. 1990:1452 (K, Mo, M, H); Wagner & Herbst 1995:21 (O); Faccenda, Arthur, et al. 2025:188 (KEY)

Occurrences

SNo. Scientific Name Locality Habitat Basis of Record Description Recorded By Record Number Island Source Date
1 Juncus bufonius East Maui, E end of Haleakala Crater along Kalapawili ridge 1 mi N of Paliku Cabins Infrequent along trail bordering grassland. Preserved_Specimen Henrickson, J.S. 3575 Maui BISH 1969-06-19
2 Juncus bufonius East Maui, Slopes of Haleakala, above Ukulele Preserved_Specimen Forbes, C.N. 172 Maui BISH 1910-07-01
3 Juncus bufonius unknown Preserved_Specimen Degener, O. 9119 BISH 1927-01-01
4 Juncus bufonius Within Haleakala, near Koolau Gap Preserved_Specimen Degener, O. 9121 Maui BISH 1927-06-29
5 Juncus bufonius Kohala Mts., Waimea Preserved_Specimen Forbes, C.N. 503 Hawaii BISH 1911-09-01
6 Juncus bufonius Kula Pipeline, Waikamoi Preserved_Specimen Forbes, C.N. 1260 Maui BISH 1919-09-05
7 Juncus bufonius East Maui, Haleakala Crater on upper switchbacks of upper Halemauu Trail Preserved_Specimen Welton, P. 2054 Maui BISH 1998-08-07
8 Juncus bufonius Kohala Mts., Waimea Preserved_Specimen Forbes, C.N. 503 Hawaii BISH 1911-09-01
9 Juncus bufonius Olinda, E of Haleakala Preserved_Specimen Hitchcock, A.S. 14903 Maui BISH 1916-10-01
10 Juncus bufonius East Maui, Slopes of Haleakala, above Ukulele Preserved_Specimen Forbes, C.N. 172 Maui BISH 1910-07-01
11 Juncus bufonius Within Haleakala, near Koolau Gap Preserved_Specimen Degener, O. 9121 Maui BISH 1927-06-29
12 Juncus bufonius Along water flume (Kula pipe Line), between Waikamoi and Haipuaena gulch, 3 to 4 mi due E of Olinda In ditch along flume through montaine rainforest. Preserved_Specimen Bonsey, E. Maui BISH 1967-08-05
13 Juncus bufonius Ukulele Preserved_Specimen Forbes, C.N. 975 Maui BISH 1919-07-29
14 Juncus bufonius Waikamoi Flume, road's end Preserved_Specimen Gagné, B.H. Maui BISH 1999-07-16
15 Juncus bufonius unknown Preserved_Specimen Degener, O. 9119 BISH 1927-01-01
16 Juncus bufonius Hana Forest Reserve Preserved_Specimen Herbst, D.R. 3043 Maui BISH 1973-08-06
17 Juncus bufonius Forest Reserve above Kamuela Preserved_Specimen Herbst, D.R. 228 Hawaii BISH 1966-08-09
18 Juncus bufonius Waimea District. Kokee State Park. Mohihi Road along Waineke Swamp Very weedy area with numberous naturalized plants - Brugmansia, Hedychium, Tropaeolum, etc. Preserved_Specimen Annual herb along road. Flynn, T.W. 2726 Kauai BISH 1988-01-28
19 Juncus bufonius Kealakekua, Kona (Baybrook) In semi-wooded pasture. Swampy place. Preserved_Specimen Hosaka, E.Y. 1474 Hawaii BISH 1936-08-05
20 Juncus bufonius East Maui, Makawao District, Haleakala, Nature Conservancy Road, near Hosmer Grove, 3x3 m area. (found on road) Very little natives; 98% conifers (Pine forest). Preserved_Specimen Lynch, E. Maui BISH 1998-07-21
21 Juncus bufonius Kilauea In driveway back of Obs.-Nat. Bldg. Preserved_Specimen A few clumps. Fagerlund, G.O. 817 Hawaii BISH 1943-08-20
22 Juncus bufonius Olinda, along pipeline trail Naturalized along trail. Preserved_Specimen Degener, O. 9124 Maui BISH 1927-06-19
23 Juncus bufonius Kalapawili Ridge, Haleakala Growing in grassland among tussocks of Deschampsia. Preserved_Specimen Harrison, B. 597 Maui BISH 1974-01-18
24 Juncus bufonius Olinda, Haleakala Ranch, Makawao Occasional in semi-wooded pasture, under trees; swampy place. Preserved_Specimen Hosaka, E.Y. 1691 Maui BISH 1937-01-15
25 Juncus bufonius Kamakou Preserve, Kawela Section, jeep road near trail to Hanalilolilo trail In center of jeep road through disturbed `ohi`a forest in the area with exotic tree plantings. Preserved_Specimen Low clumps. Culms reddish in color. Cuddihy, L.W. 1208 Molokai BISH 1982-05-27
26 Juncus bufonius East Maui, E rim of Haleakala, 1/2 way up Lauulu Trail Common along trail in disturbed areas. Preserved_Specimen Henrickson, J.S. 3575 Maui BISH 1969-06-19
27 Juncus bufonius Side of Waikolu Gulch Wet places on trail. Preserved_Specimen St.John, H. 12435 Molokai BISH 1932-12-21
28 Juncus bufonius East Maui, Along Olinda Flume, Waikamoi Very common weed along Flume. Preserved_Specimen Crosby, M.R. 1782 Maui BISH 1964-07-16
29 Juncus bufonius Waianae Mts., Kaala Boardwalk Bog environment. Along Kaala boardwalk on the right side when facing towards the parking lot. Preserved_Specimen Large Juncus, ca 1 m tall. Seeds light brown. There were several plants sporadically along the boardwalk, amongst Juncus planifolius, and several Cyperus species. Van Gent, S. 566 Oahu BISH 2022-02-07
30 Juncus bufonius [Hawaiian Islands; U.S.A.; Hawaii In swampy kepuka. Preserved_Specimen Hosaka, E.Y. 1526 BISH 1936-08-21
31 Juncus bufonius N of H. Exp. Station, Wright Road Naturalized in muddy clearing. Preserved_Specimen Degener, O. 31528 Hawaii BISH 1967-07-18
32 Juncus bufonius East Maui, above Ukulele In pasture, in a damp erosion gully. Preserved_Specimen Forbes, C.N. 975 Maui BISH 1919-07-29
33 Juncus bufonius Kahuku-Kau Forest Reserve, jeep road to Nene Cabin In gravel of road bed. Preserved_Specimen St.John, H. 26788 Hawaii BISH 1971-06-24
34 Juncus bufonius Olinda Pipeline, Makawao Forest Reserve Roadside in rainforest, growing in water. Preserved_Specimen Herbaceous. Woolford, H.A. 123 Maui BISH 1955-12-25
35 Juncus bufonius Haleakala National Park, 1/2 mi W of Palikea Occasionally seen in boggy places throughout crater. Preserved_Specimen Marsh grass, 9 high. Olson, G.E. 86 Maui BISH 1937-08-26
36 Juncus bufonius Kauaikinana Stream, along Mohihi Rd Roadside. Preserved_Specimen Wagner, W.L. 6041 Kauai BISH 1988-04-09
37 Juncus bufonius S Hilo, Humuula, Humuula Sheep Sta Occasional; local patches. Preserved_Specimen Hosaka, E.Y. 2333 Hawaii BISH 1938-06-13
38 Juncus bufonius Kau Forest Reserve, Mt. House Trail Common along roadside. Wet w/ tree ferns, Metrosideros, Tibouchina Preserved_Specimen Herbst, D.R. 199 Hawaii BISH 1966-08-04
39 Juncus bufonius Kokee State Park, Kauai, Hawaii Growing in upper parking area, just below Pihea lookout, in the cracked asphault and potholes, wet to ponding. Preserved_Specimen Clumping fine Juncus, short and spikey. Crago, L.M. 2005167 Kauai BISH 2005-08-03
40 Juncus bufonius East Maui, Hosmer Grove, just first ohia tree (before tnc gate Pine forest Preserved_Specimen Lynch, E. Maui BISH 1998-07-21
41 Juncus bufonius East Maui, Kula Pipeline, Olinda In wet trail. Preserved_Specimen St.John, H. 10304 Maui BISH 1930-02-11
42 Juncus bufonius Near upper end of Hanalilolilo pipeline Along marshy trail in open. Preserved_Specimen Degener, O. 9120 Molokai BISH 1928-04-24
43 Juncus bufonius Hill mauka of Olinda on way to Haleakala In wet exposed locality accessible to cattle. Preserved_Specimen Degener, O. 12322 Maui BISH 1927-06-15
44 Juncus bufonius East Maui, Waikamoi Rainforest. Preserved_Specimen Neal, M.C. Maui BISH 1933-08-14
45 Juncus bufonius Olinda, along pipeline trail Naturalized along trail. Preserved_Specimen Degener, O. 9124 Maui BISH 1927-06-19
46 Juncus bufonius Between Glenwood and Volcano House Preserved_Specimen Degener, O. 9122 Hawaii BISH 1926-07-27