General: Madder Family (Rubiaceae). Common buttonbush is a warm-season shrub or small tree that reaches 6 m in height at maturity. Stem bases are swollen. Young twigs are green, 4-sided with elongated lenticels, and turn brown and scaly upon maturation. Leaves are opposite or whorled, lance-shaped, 18 cm long and 7.5 cm wide, glossy dark green, and emerge in May. Flowers are tubular, 4- to 5-lobed, white to reddish, 4 cm across, and form in dense clusters at the ends of the branches. Long styles give flowers a pincushion appearance. The fruit are ball-like and contain 2-seeded nutlets. Common buttonbush blooms in June through September and sets fruit in September and October.
Key characteristics of common buttonbush are its pincushion flower heads, elongated lenticels, and swollen stem bases. It is also the only wetland shrub that has whorled leaves and spherical-shaped flowers.
Distribution: Common buttonbush is native to North America. It occurs from Nova Scotia to Ontario, south through Florida, and west to the eastern Great Plains with scattered populations in New Mexico, Arizona, California, and northern Mexico. For current distribution, please consult the Plant Profile page for this species on the PLANTS Web site (http://plants.usda.gov).
Habitat: Common buttonbush is a wetland shrub common in swamps, floodplains, marshes, bogs, ditches that are underwater for part of the year, and alluvial plains with intermittent flooding. It is present in riparian and wetland communities and is associated with plants like American beech, red maple, sugar maple, black oak, pin oak, Nyssa species, bald cypress, southern bayberry, red bay, holly, dogberry, grape, viburnum, poison ivy, Indian grass, big bluestem, switchgrass, and sedges.
Button ball, button willow, buttonbush, Cephalanthus occidentalis var. californicus, Cephalanthus occidentalis var. pubescens, honey-bells, riverbush.
Range and Habitat in Illinois
Regularity: Regularly occurring
Regularity: Regularly occurring
Ontario south through southern Florida and west through the eastern
half of the Great Plains States [8,16]. Scattered populations exist in
New Mexico, Arizona, and the central valley of California . The
variety californicus is found in California; the variety pubescens is
found from southeast Virginia to Georgia and Texas, southern Ontario,
Indiana, Illinois, and Oklahoma . Distribution of the variety
angustifolius was not listed.
Regional Distribution in the Western United States
This species can be found in the following regions of the western United States (according to the Bureau of Land Management classification of Physiographic Regions of the western United States):
3 Southern Pacific Border
7 Lower Basin and Range
12 Colorado Plateau
13 Rocky Mountain Piedmont
14 Great Plains
Occurrence in North America
IA KS KY LA ME MA MI MN MS MO
NE NH NJ NM NC OH OK PA RI SC
TN TX VT VA WV WI NB NS ON PQ
The USDA hardiness zones for common buttonbush are 5 through 9. It is a pioneer species in flooded areas and colonizes lowland marsh communities dominated by hardstem bulrush. It grows well in sandy, loamy soils or alluvial soils with sand or silt surfaces. It favors acidic or neutral soils and is intolerant of alkalinity. It prefers medium to wet moisture levels and is intolerant of dry soils. Abundance increases with increased water levels and with increased light levels. Its distribution is limited to regions that have a mean July temperature of 20oC.
Buttonbush is a deciduous, warm-season, tall shrub or small tree that
can reach up to 18 feet (6 m) in height . Its base is often
swollen. Branches are usually green when young but turn brown at
maturity. Buttonbush has opposite, lanceolate-oblong leaves about 7
inches (18 cm) long and 3 inches (7.5 cm) wide . Tiny, white
flowers occur in dense, spherical clusters at the ends of the branches.
Fruits are a round cluster of brown, cone-shaped nutlets. The variety
angustifolius usually has leaves in whorls of threes . The variety
pubescens has hairs on the lower leaf surfaces . The variety
californicus has more lanceolate leaves than the other two varieties
Catalog Number: US 1971681
Collection: Smithsonian Institution, National Museum of Natural History, Department of Botany
Preparation: Pressed specimen
Collector(s): M. L. Fernald
Year Collected: 1946
Locality: Shore of Dardens Pond north of Courtland., Southampton, Virginia, United States, North America
Catalog Number: US 338113
Collection: Smithsonian Institution, National Museum of Natural History, Department of Botany
Verification Degree: Card file verified by examination of original publication
Preparation: Pressed specimen
Collector(s): G. Hansen
Year Collected: 1895
Locality: Crow Point., Amador, California, United States, North America
Elevation (m): 1500 to 1500
Range and Habitat in Illinois
riparian areas that are inundated for at least part of the year [8,24].
It grows in alluvial plains that experience intermittant flooding, but
can be damaged by spring flooding [12,20,23]. Faber-Langendoen and
Maycock  reported that buttonbush was very tolerant of flooding and
that its abundance increased with increasing water depth. These authors
also reported an increase in buttonbush with an increase in light level.
Elevational and geographical distribution of buttonbush may be limited
by mean July temperatures of 68 degrees Fahrenheit (20 deg C) .
Elevations have been reported at 635 feet (193 m) in Illinois  and
between 60 and 160 feet (22-50 m) in Quebec . Buttonbush was found
growing in sandy, loamy sandy, or alluvial soil with a sandy or silty
surface in Quebec .
Common associates of buttonbush include American beech (Fagus
grandifolia), red maple (Acer rubrum), sugar maple (A. saccharum), ash
(Fraxinus spp.), black oak (Quercus velutina), pin oak (Q. palustris),
tupelo and gum (Nyssa spp.), baldcypress (Taxodium distichum), southern
bayberry (Myrica cerifera), redbay (Persea palustris), holly (Ilex
spp.), dogberry (Ribes cynosbati), grape (Vitis spp.), viburnum
(Viburnum spp.), poison-ivy (Toxicodendron radicans), indiangrass
(Sorgastrom nutans), big bluestem (Andropogon gerardii), switchgrass
(Panicum virgatum), and sedge (Carex spp.) [5,7,11].
Key Plant Community Associations
Buttonbush is a wetland shrub common to most swamps and floodplains of
eastern and southern North America [8,28]. It is listed as a component
of the following community types:
Area Classification Authority
CA: Sacramento Valley riparian cts Conard & others 1977
United States wetland cts Cowardin & others 1979
Habitat: Cover Types
This species is known to occur in association with the following cover types (as classified by the Society of American Foresters):
More info for the term: swamp
14 Northern pin oak
19 Grey birch - red maple
26 Sugar maple - basswood
27 Sugar maple
28 Black cherry - maple
39 Black ash - American elm - red maple
43 Bear oak
64 Sassafras - persimmon
65 Pin oak - sweet gum
74 Cabbage palmetto
87 Sweet gum - yellow-poplar
88 Willow oak - water oak - diamondleaf oak
89 Live oak
91 Swamp chestnut oak - cherrybark oak
92 Sweetgum - willow oak
93 Sugarberry - American elm - green ash
94 Sycamore - sweetgum - American elm
95 Black willow
96 Overcup oak - water hickory
102 Baldcypress - tupelo
103 Water tupelo - swamp tupelo
104 Sweetbay - swamp tupelo - redbay
105 Tropical hardwoods
108 Red maple
235 Cottonwood - willow
Habitat: Plant Associations
This species is known to occur in association with the following plant community types (as classified by Küchler 1964):
K030 California oakwoods
K049 Tule marshes
K080 Marl - Everglades
K091 Cypress savanna
K098 Northern floodplain forest
K099 Maple - basswood forest
K100 Oak - hickory forest
K101 Elm - ash forest
K102 Beech - maple forest
K103 Mixed mesophytic forest
K104 Appalachian oak forest
K106 Northern hardwoods
K110 Northeastern oak - pine forest
K112 Southern mixed forest
K113 Southern floodplain forest
This species is known to occur in the following ecosystem types (as named by the U.S. Forest Service in their Forest and Range Ecosystem [FRES] Type classification):
FRES15 Oak - hickory
FRES16 Oak - gum - cypress
FRES17 Elm - ash - cottonwood
FRES18 Maple - beech - birch
FRES32 Texas savanna
FRES41 Wet grasslands
FRES42 Annual grasslands
Flower-Visiting Insects of Buttonbush in Illinois
(bees usually suck nectar and less often collect pollen; beetles feed on pollen and are non-pollinating; other insects suck nectar; some observations are from Estes & Thorp, Steury et al., and Tuell et al. as indicated below, otherwise observations are from Robertson)
Apidae (Apinae): Apis mellifera sn fq; Apidae (Bombini): Bombus auricomus sn fq, Bombus bimaculatus sn (Rb, SDO), Bombus fraternus sn, Bombus griseocollis sn fq (Rb, SDO), Bombus impatiens sn cp fq (Rb, SDO, Tll), Bombus pensylvanicus sn cp fq, Bombus perplexus (SDO), Psithyrus variabilis sn; Anthophoridae (Ceratinini): Ceratina dupla dupla sn; Anthophoridae (Emphorini): Ptilothrix bombiformis sn; Anthophoridae (Epeolini): Triepeolus concavus sn, Triepeolus lunatus concolor sn fq, Triepeolus lunatus lunatus sn; Anthophoridae (Eucerini): Florilegus condigna sn, Melissodes spp. (Tll), Melissodes bimaculata bimaculata sn, Melissodes communis sn cp, Melissodes tepaneca sn, Peponapis pruinosa pruinosa sn, Svastra obliqua obliqua sn cp fq; Megachilidae (Megachilini): Megachile brevis brevis sn fq, Megachile inimica sayi sn, Megachile mendica cp (Rb, SDO), Megachile parallela parallela sn, Megachile petulans sn
Halictidae (Halictinae): Agapostemon sericea sn, Agapostemon texanus texanus sn, Agapostemon virescens sn (Rb, Tll), Augochlora pura (SDO), Halictus ligatus sn, Halictus rubicundus sn, Lasioglossum admirandum (Tll), Lasioglossum laevissimum (SDO), Lasioglossum lustrans sn np (ET); Colletidae (Hylaeinae): Hylaeus affinis cp np
Sphecidae (Sphecinae): Ammophila nigricans; Tiphiidae: Myzinum quinqecincta; Pompilidae: Entypus fulvicornis; Vespidae (Eumeninae): Euodynerus annulatus
Syrphidae: Eristalis stipator, Eristalis tenax fq, Sphaerophoria contiqua, Syritta pipiens, Volucella bombylans; Conopidae: Physocephala texana, Physocephala tibialis, Physoconops brachyrhynchus; Muscidae: Musca domestica
Nymphalidae: Cercyonis pegala alope, Danaus plexippus fq, Limenitis archippus, Phyciodes tharos fq, Speyeria cybele, Vanessa atalanta fq, Vanessa cardui, Vanessa virginiensis; Lycaenidae: Celastrina argiolus, Everes comyntas, Lycaena hyllus fq, Strymon melinus; Papilionidae: Battus philenor, Papilio polyxenes asterias fq, Papilio troilus; Pieridae: Colias cesonia, Colias philodice, Pieris rapae, Pontia protodice fq
Hesperiidae: Anatrytone logan, Atalopedes campestris, Epargyreus clarus fq, Erynnis juvenalis fq, Poanes zabulon, Polites peckius, Polites themistocles fq, Thorybes bathyllus
Arctiidae: Utetheisa bella; Ctenuchidae: Cisseps fulvicollis
Coccinellidae: Hippodamia convergens fp np; Scarabaeidae: Trichiotinus piger fp np
Lygaeidae: Oncopeltus fasciatus
Fire Management Considerations
In Southern marshlands, where grasses are thick and impenetrable, fire
can reduce grass densities and release nutrients, which enhances
establishment of shrubs such as buttonbush .
Broad-scale Impacts of Plant Response to Fire
Buttonbush can become the dominant shrub in grassy, wetland areas of the
South excluded from fire . However, when these areas are burned
buttonbush has been observed sprouting within a few months following
fire [9,11,29]. Frequent fires in harwood swamps of the South often
promote willow sprouting and, occasionally, buttonbush sprouting .
Following 2 years of drought, a severe fire in an area of the Okefenokee
Swamp that supported buttonbush killed most of the trees and consumed a
1-inch (2.45 cm) layer of peat . Buttonbush resprouted 7 years
Because the base of buttonbush shrubs are partially submerged during
most of the year, fire may not be a threat.
Buttonbush is a pioneer species in frequently flooded baldcypress/water
tupelo (Nyssa aquatica) swamps, establishing on rotting logs and stumps
. In the Sacremento Valley, buttonbush/dogwood (Corunus spp.)
communities are succeeded by white alder (Alnus rhombifolia)/willow
(Salix spp.)/Oregon ash (Fraxinus latifolia) and eventually cottonwood
(Populus spp.) forests . Buttonbush also colonizes lowland marsh
communities dominated by hardstem bulrush (Scirpus acutus).
Growth Form (according to Raunkiær Life-form classification)
have turned reddish-brown, and averages about 134,000 per pound
(60,702/kg) . Pretreatment of seeds is unnecessary . Seeds have
a low germination rate . Buttonbush can also be propagated by
planting cuttings in moist, sandy soil.
Plant Response to Fire
Life History and Behavior
Molecular Biology and Genetics
Barcode data: Cephalanthus occidentalis
Statistics of barcoding coverage: Cephalanthus occidentalis
Public Records: 2
Specimens with Barcodes: 4
Species With Barcodes: 1
National NatureServe Conservation Status
Rounded National Status Rank: NNR - Unranked
Rounded National Status Rank: N5 - Secure
NatureServe Conservation Status
Rounded Global Status Rank: G5 - Secure
Much of buttonbush's natural habitat in California is being destroyed by
agriculture and water development projects; buttonbush is not a good
colonizer of manmade waterways . Buttonbush is moderately
susceptible to herbicides; if shrubs become too thick, they can be
reduced by cutting in the fall during low water [4,18].
Cultivars, improved and selected materials (and area of origin)
In 1996, the Big Flats Plant Materials Center released the ‘Keystone’ common buttonbush cultivar for use in wetland and riparian area restoration for the entire common buttonbush range. ‘Keystone’ was selected for its increased plant vigor, stem and foliar abundance, and increased basal area.
Contact your local Natural Resources Conservation Service (formerly Soil Conservation Service) office for more information. Look in the phone book under ”United States Government.” The Natural Resources Conservation Service will be listed under the subheading “Department of Agriculture.”
Common buttonbush seeds are ready for collection in the fall when they have turned reddish-brown. No pretreatment is necessary. Sow seeds into moist, humus soils in full sun or part shade.
Cuttings will produce roots in moist sandy soil. Unrooted cuttings can be pushed into moist soil along shorelines and will establish on their own.
Common buttonbush does not colonize along manmade waterways. It is moderately susceptible to herbicides and can be damaged by springtime flooding. Pruning is not necessary for control of spread but can be done in the spring to shape the plant. Dense shrubs can be cut back in the fall, when water levels are low, to maintain manageability.
It has been found in the South that common buttonbush remains dominant in the absence of fire. It will resprout in a few months following low-intensity burns in wet woodlands. Frequent fires will promote occasional sprouting, but common buttonbush is slow to resprout (7 years) following high-intensity burns. In the southern marshlands, fire decreases grass densities, releasing nutrients for common buttonbush, and increasing growth.
Relevance to Humans and Ecosystems
Other uses and values
for curing skin, bronchial, and venereal diseases . Caution must be
used, however, because the bark contains cephalathin, a poison that can
induce vomitting, paralysis, and convulsions.
Importance to Livestock and Wildlife
White-tailed deer use of buttonbush browse varies from light in
Pennsyvania  to heavy in Nova Scotia . Bees use buttonbush to
produce honey .
Erosion control: Common buttonbush is used for erosion control along shorelines. It forms dense stands and its swollen plant base stabilizes the plant.
Ethnobotanic: Native Americans used common buttonbush medicinally. Decoctions of the bark were used as washes for sore eyes, antidiarrheal agents, anti-inflammation and rheumatism medications, skin astringents, headache and fever relievers, and venereal disease remedies. The bark was also chewed to relieve toothaches. Roots were used for muscle inflammation and as blood medicines.
Ornamental: Showy flowers and fruit make common buttonbush a popular choice for use in native plant gardens, shrub borders, and along pond shores and water gardens. The persistent fruits give the plant some winter interest.
Wildlife: Waterfowl and shorebirds consume the seeds of common buttonbush. White-tailed deer browse foliage in the northeastern United States. Wood ducks use the plant’s structure for protection of brooding nests. Butterflies, bees, and hummingbirds are attracted to common buttonbush for its nectar. Bees use it to produce honey.
Cephalanthus occidentalis is a species of flowering plant in the coffee family, Rubiaceae, that is native to eastern and southern North America. Common names include Buttonbush, Common Buttonbush, Button-willow and Honey-bells.
C. occidentalis is a deciduous shrub or small tree that averages 1–3 m (3.3–9.8 ft) in height, but can reach 6 m (20 ft). The leaves are opposite or in whorls of three, elliptic to ovate, 7–18 cm (2.8–7.1 in) long and 4–10 cm (1.6–3.9 in) broad, with a smooth edge and a short petiole. The flowers are arranged in a dense spherical inflorescence 2–3.5 cm (0.79–1.38 in) in diameter on a short peduncle. Each flower has a fused white to pale yellow four-lobed corolla forming a long slender tube connecting to the sepals. The stigma protrudes slightly from the corolla. The fruit is a spherical cluster of achenes (nutlets).
There are two varieties, not considered distinct by all authorities:
- Cephalanthus occidentalis var. occidentalis (syn. var. pubescens) – Common Buttonbush. Eastern North America from Nova Scotia west to Minnesota and south to Florida and eastern Texas.
- Cephalanthus occidentalis var. californicus – California Button-willow. Southwestern North America, from western Texas west to California (Sierra Nevada foothills, San Joaquin Valley, Sacramento Valley, and the Inner North Coast Ranges) and south to Mexico and Central America.
Buttonbush is a common shrub of many wetland habitats in its range, including swamps, floodplains, mangrove, pocosin, riparian zones, and moist forest understory. It is a member of the flora in the Everglades.
The species occurs in eastern North America with disjunct populations occurring in the west. In Canada, it occurs from southern Ontario and Quebec east to New Brunswick. Besides the eastern United States, and eastern regions of the Midwest, notable areas range into Arizona, the Mogollon Rim, and other mountain ranges; in California, the entire San Joaquin Valley West of the Great Plains and the Rocky Mountains, only western Texas, Arizona, and California find C. occidentalis.
Buttonbush is cultivated as an ornamental plant for a nectar source or 'honey plant' and for aesthetics in gardens and native plant landscapes, and is planted on slopes to help control erosion. Buttonbush is a suitable shrub for butterfly gardens.
San Joaquin Valley landmark tree
The town of Buttonwillow, California was named for the Buttonbush (Cephalanthus occidentalis). A lone buttonbush served as a landmark on an old trans-San Joaquin Valley trail, and was used by ancient Yokut Indians as a meeting place. It later became the site of settlers' stock rodeos. This buttonbush tree is listed as California Historical Landmark No. 492, and is now known as the "Buttonwillow Tree."
- "Cephalanthus occidentalis L.". Germplasm Resources Information Network. United States Department of Agriculture. 1994-08-23. Retrieved 2010-01-04.
- "Cephalanthus occidentalis L. buttonbush" (PDF). Wildland Shrubs of the United States and its Territories: Thamnic Descriptions. United States Forest Service. Retrieved 2009-09-14.
- "Cephalanthus occidentalis". Fire Effects Information System. United States Forest Service.
- "Common Buttonbush Cephalanthus occidentalis L." (PDF). Natural Resources Conservation Service Plant Guide. United States Department of Agriculture.
- Little. Atlas of United States Trees, Volume 3, Minor Western Hardwoods, Little, Elbert L, 1976, US Government Printing Office. Library of Congress No. 79-653298. Map 34-NW, Map 34-SW, Cephalanthus occidentalis.
- O'Sullivan, Penelope (2007). The Homeowner's Complete Tree & Shrub Handbook: The Essential Guide to Choosing, Planting, and Maintaining Perfect Landscape Plants. Storey Publishing. p. 197. ISBN 978-1-58017-571-5.
Names and Taxonomy
occidentalis L. (Rubiaceae) . Recognized varieties are as follows
C. occidentalis var. pubescens (Raf.)
C. occidentalis var. californicus (Benth.)
C. occidentalis var. angustifolius (Dippel)
EOL content is automatically assembled from many different content providers. As a result, from time to time you may find pages on EOL that are confusing.
To request an improvement, please leave a comment on the page. Thank you!