Ceanothus Martinii
   HOME

TheInfoList



OR:

''Ceanothus'' is a genus of about 50–60 species of nitrogen-fixing
shrub A shrub (often also called a bush) is a small-to-medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees ...
s and small trees in the
buckthorn family The Rhamnaceae are a large family of flowering plants, mostly trees, shrubs, and some vines, commonly called the buckthorn family. Rhamnaceae is included in the order Rosales. The family contains about 55 genera and 950 species. The Rhamnaceae h ...
(
Rhamnaceae The Rhamnaceae are a large family of flowering plants, mostly trees, shrubs, and some vines, commonly called the buckthorn family. Rhamnaceae is included in the order Rosales. The family contains about 55 genera and 950 species. The Rhamnaceae h ...
). Common names for members of this genus are buckbrush, California lilac, soap bush, or just ceanothus. ''"Ceanothus"'' comes from grc, κεάνωθος (''keanōthos''), which was applied by Theophrastus (371–287 BC) to an Old World plant believed to be '' Cirsium arvense''. The genus is native to
North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...
with the highest diversity on the western coast. Some species (e.g., '' C. americanus'') are restricted to the eastern United States and southeast Canada, and others (e.g., '' C. caeruleus'') extend as far south as Guatemala. Most are shrubs tall, but '' C. arboreus'' and '' C. thyrsiflorus'', both native to California, can be small multi-trunked trees up to tall.


Taxonomy and etymology

There are two subgenera within this genus: ''Ceanothus'' and ''Cerastes''. The former clade is less drought-resistant, having bigger leaves. The evolution of these two clades likely started with a divergence in the niches filled in local communities, rather than a divergence on the basis of geography. The Californian species of ''Ceanothus'' are commonly known collectively as California lilacs, with individual species having more descriptive common names. Species native elsewhere have other common names such as New Jersey tea for ''C. americanus'', as its leaves were used as a black tea substitute during the American Revolution. In garden use, most are simply called by their scientific names or an adaptation of the scientific name, such as 'Maritime ceanothus' for ''C. maritimus''.


Species

, accepted species are: * '' Ceanothus americanus'' L. – New Jersey tea; red root * '' Ceanothus arboreus'' Greene – feltleaf ceanothus * '' Ceanothus arcuatus'' McMinn * '' Ceanothus bolensis'' S.Boyd & J.E.Keeley * '' Ceanothus buxifolius'' Willd. ex Schult. & Schult.f. * ''
Ceanothus caeruleus ''Ceanothus caeruleus'' is a species of ''Ceanothus'' shrub first described by Mariano Lagasca y Segura. ''Ceanothus caeruleus'' is part of the genus ''Ceanothus'' and the family Rhamnaceae The Rhamnaceae are a large family of flowering plants ...
'' Lag * ''
Ceanothus confusus ''Ceanothus confusus'' is a species of shrub in the family Rhamnaceae known by the common name Rincon Ridge ceanothus. It is endemic to northern California where it grows in the coastal mountains north of the San Francisco Bay Area. Its habit ...
'' J.T. Howell – Rincon Ridge ceanothus * '' Ceanothus connivens'' Greene – trailing buckbrush * ''
Ceanothus cordulatus ''Ceanothus cordulatus'' is a species of shrub in the family Rhamnaceae known by the common names mountain whitethorn and whitethorn ceanothus. It is native to California and adjacent sections of Oregon, Nevada, and Baja California, where it ...
'' Kellogg – whitethorn ceanothus * '' Ceanothus crassifolius'' Torr. – hoaryleaf ceanothus * '' Ceanothus cuneatus'' (Hook.) Nutt. – buckbrush ** subsp. ''cuneatus'' (Hook.) Nutt. ** subsp. ''fascicularis'' (McMinn) C.L.Schmidt ** subsp. ''rigidus'' (Nutt.) C.L.Schmidt ** subsp. ''sonomensis'' (Howell) C.L.Schmidt * '' Ceanothus cyaneus'' Eastw. – San Diego buckbrush * '' Ceanothus decornutus'' V.T.Parker * ''
Ceanothus dentatus ''Ceanothus dentatus'' is a species of shrub in the family Rhamnaceae known by the common name sandscrub ceanothus. It is endemic to California, where it is known only from the Central Coast and its Coast Ranges. It grows in coastal hills, bl ...
'' Torr. & A.Gray – sandscrub ceanothus * ''
Ceanothus depressus ''Ceanothus depressus'' Benth.Bentham, Planta Hartwegiana 8. 1839. is a shrub in the family Rhamnaceae, native to the Mexican states of Chihuahua and Sonora Sonora (), officially Estado Libre y Soberano de Sonora ( en, Free and Sovereign Stat ...
'' Benth. – junco * ''
Ceanothus divergens ''Ceanothus divergens'', commonly known as Calistoga ceanothus, is an evergreen shrub in the family Rhamnaceae, an endemic of California. Description This plant has a growth habit described as ascending to erect and may attain height. The pl ...
'' Parry – Calistoga ceanothus * ''
Ceanothus diversifolius ''Ceanothus diversifolius'' is a species of flowering shrub known by the common name pinemat. This '' Ceanothus'' is endemic to California, where it can be found in the oak and pine forests of several mountain ranges. Description This is a spra ...
'' Kellogg – pinemat * ''Ceanothus fendleri'' A.Gray – Fendler's ceanothus * ''Ceanothus ferrisiae'' McMinn – coyote ceanothus * ''Ceanothus foliosus'' Parry – wavyleaf ceanothus ** subsp. ''foliosus'' Parry ** subsp. ''medius'' (McMinn) C.L.Schmidt ** subsp. ''vineatus'' (McMinn) C.L.Schmidt * ''Ceanothus fresnensis'' Dudley ex Abrams – Fresno ceanothus * ''Ceanothus gloriosus'' J.T. Howell – Point Reyes ceanothus ** subsp. ''exaltatus'' (Howell) C.L.Schmidt ** subsp. ''gloriosus'' J.T. Howell ** subsp. ''masonii'' (McMinn) C.L.Schmidt ** subsp. ''porrectus'' (Howell) C.L.Schmidt * ''Ceanothus griseus'' (Trel. ex B.L.Rob.) McMinn – Carmel ceanothus * ''Ceanothus hearstiorum'' Hoover & J.B.Roof – Hearst Ranch buckbrush * ''Ceanothus herbaceus'' Raf. – Jersey tea * ''Ceanothus impressus'' Trel. – Santa Barbara ceanothus * ''Ceanothus incanus'' Torr. & A.Gray – coast whitethorn * ''Ceanothus integerrimus'' Hook. & Arn. – deerbrush ceanothus * ''Ceanothus jepsonii'' Greene – Jepson ceanothus ** subsp. ''albiflorus'' (Howell) C.L.Schmidt ** subsp. ''jepsonii'' Greene * ''Ceanothus lanuginosus'' (M.E.Jones) Rose * ''Ceanothus lemmonii'' Parry – Lemmon's ceanothus * ''Ceanothus leucodermis'' Greene – chaparral whitethorn * ''Ceanothus maritimus'' Hoover – maritime ceanothus * ''Ceanothus martinii'' M.E.Jones – Martin's ceanothus * ''Ceanothus masonii'' McMinn – Mason's ceanothus * ''Ceanothus megacarpus'' Nutt. – bigpod ceanothus ** subsp. ''insularis'' (Eastw.) P.H.Raven ** subsp. ''megacarpus'' Nutt. * ''Ceanothus microphyllus'' Michx. – littleleaf buckbrush * ''Ceanothus ochraceus'' Suess. * ''Ceanothus oliganthus'' Nutt. – hairy ceanothus ** subsp. ''oliganthus'' Nutt. ** subsp. ''sorediatus'' (Hook. & Arn.) C.L.Schmidt * ''Ceanothus ophiochilus'' Boyd, Ross & Arnseth – Vail Lake ceanothus * ''Ceanothus otayensis'' H. E. McMinn – Otay Mountain buckbrush * ''Ceanothus palmeri'' Trel. – Palmer ceanothus * ''Ceanothus papillosus'' Torr. & A.Gray – wartleaf ceanothus * ''Ceanothus parryi'' Trel. – Parry Ceanothus * ''Ceanothus parvifolius'' (S.Watson) Trel. – littleleaf ceanothus * ''Ceanothus pauciflorus'' DC. * ''Ceanothus pendletonensis'' D.O.Burge, Rebman, & M.R.Mulligan * ''Ceanothus perplexans'' Trel. * ''Ceanothus pinetorum'' Coville – Coville ceanothus * ''Ceanothus prostratus'' Benth. – prostrate ceanothus ** subsp. ''confusus'' (Howell) C.L.Schmidt ** subsp. ''prostratus'' Benth. ** subsp. ''pumilus'' (Greene) C.L.Schmidt * ''Ceanothus pumilus'' Greene – dwarf ceanothus * ''Ceanothus purpureus'' Jepson – hollyleaf ceanothus ** subsp. ''divergens'' (Parry) C.L.Schmidt ** subsp. ''purpureus'' Jepson * ''Ceanothus roderickii'' Knight – Pine Hill buckbrush * ''Ceanothus sanguineus'' Pursh – redstem ceanothus * ''Ceanothus serpyllifolius'' Nutt. – Coastal Plain buckbrush * ''Ceanothus sonomensis'' J.T. Howell – Sonoma ceanothus * ''Ceanothus spinosus'' Nutt. – green bark ceanothus * ''Ceanothus thyrsiflorus'' Eschsch. – blueblossom * ''Ceanothus tomentosus'' Parry – woolyleaf ceanothus * ''Ceanothus velutinus'' Dougl. ex Hook. – snowbrush ceanothus ** subsp. ''laevigatus'' (Torr. & A.Gray) Piper & Beattie ** subsp. ''velutinus'' Dougl. ex Hook. * ''Ceanothus verrucosus'' Nutt. – Barranca brush


Species names with uncertain taxonomic status

The status of the following species is unresolved: * ''Ceanothus atropurpureus'' Raf. * ''Ceanothus chloroxylon'' Nees * ''Ceanothus collinus'' Douglas ex Knowles & Westc. * ''Ceanothus cuneatus'' A.Gray * ''Ceanothus cuneatus'' K.Brandegee * ''Ceanothus divergens'' Poepp. ex Endl. * ''Ceanothus elongatus'' Salisb. * ''Ceanothus flexilis'' McMinn * ''Ceanothus glaber'' Spach * ''Ceanothus laevigatus'' Howell * ''Ceanothus lancifolius'' Moench * ''Ceanothus leschenaultii'' DC. * ''Ceanothus mocinianus'' DC. * ''Ceanothus mystacinus'' DC. * ''Ceanothus neumannii'' Tausch * ''Ceanothus oblanceolatus'' Davidson * ''Ceanothus pauciflorus'' Moc. & Sessé ex DC. * ''Ceanothus pubiflorus'' DC. * ''Ceanothus pulchellus'' Delile ex Spach * ''Ceanothus scandens'' D.Dietr. * ''Ceanothus spathulatus'' Labill. * ''Ceanothus spinosus'' Torr. & A. Gray * ''Ceanothus triqueter'' Wall. * ''Ceanothus vanrensselaeri'' Roof


Hybrids

The following hybrids have been described: * ''Ceanothus'' × ''arcuatus'' McMinn * ''Ceanothus'' × ''bakeri'' Greene ex McMinn * ''Ceanothus'' × ''flexilis'' McMinn * ''Ceanothus'' × ''lobbianus'' Hook. * ''Ceanothus'' × ''lorenzenii'' (Jeps.) McMinn * ''Ceanothus'' × ''mendocinensis'' McMinn * ''Ceanothus'' × ''otayensis'' McMinn * ''Ceanothus'' × ''rugosus'' Greene * ''Ceanothus'' × ''serrulatus'' McMinn * ''Ceanothus'' × ''vanrensselaeri'' Roof * ''Ceanothus'' × ''veitchianus'' Hook.


Hybrid names with uncertain taxonomic status

The status of the following hybrids is unresolved: * ''Ceanothus'' × ''arnoldii'' Dippel * ''Ceanothus'' × ''burkwoodii'' auct. * ''Ceanothus'' × ''burtonensis'' Renss. * ''Ceanothus'' × ''cyam'' L.W.Lenz * ''Ceanothus'' × ''delilianus'' Spach * ''Ceanothus'' × ''humboldtensis'' Roof * ''Ceanothus'' × ''intermedius'' Koehne * ''Ceanothus'' × ''pallidus'' Koehne * ''Ceanothus'' × ''pallidus'' Lindl. * ''Ceanothus'' × ''roseus'' Koehne


Description


Growth pattern

The majority of the species are evergreen, but the handful of species adapted to cold winters are deciduous. The leaves are opposite or alternate (depending on species), small (typically 1–5 cm long), simple, and mostly with serrated margins.


Leaves and stems

Ceanothus leaves may be arranged opposite (leaf), opposite to each other on the stem, or alternate (leaf), alternate. Alternate leaves may have either one or three main veins rising from the base of the leaf.Native Shrubs of the Sierra Nevada, John Hunter Thomas, Dennis R. Parnell, University of California Press, 1974, p. 70–77

/ref> The leaves have a shiny upper surface that feels "gummy" when pinched between the thumb and forefinger, and the roots of most species have red inner root bark.Edible and Medicinal Plants of the West, Gregory L. Tilford,


Flowers and fruit

The flowers are white, greenish–white, blue, dark purple-blue, pale purple or pink, maturing into a dry, three-lobed seed capsule. The flowers are tiny and fragrant and produced in large, dense clusters. A few species are reported to be so intensely fragrant they are almost nauseating, and are said to resemble the odor of "boiling honey in an enclosed area". The seeds of this plant can lie dormant for hundreds of years, and ''Ceanothus'' species are typically dependent on forest fires to trigger germination of their seeds. Fruits are hard, nutlike capsules.Flowering Plants of the Santa Monica Mountains, Nancy Dale, 2nd Ed., 2000, pp. 166–167


Distribution

Plants in this genus are widely distributed and can be found on dry, sunny hillsides from coastal scrub lands to open forest clearings, from near sea level to in elevation. These plants are profusely distributed throughout the Rocky Mountains from British Columbia south through Colorado, the Cascades of Oregon and California, and the Coastal Ranges of California. ''Ceanothus velutinus'' is perhaps the most widespread member of this genus, occurring through much of western North America. The plants in this genus often co-occur with one another, especially when they are more distantly related.


Uses


Wildlife

Ceanothus is a good source of nutrition for deer, specifically mule deer along the West Coast of the United States. However, the leaves are not as nutritious from late spring to early fall as they are in early spring. Porcupines and quail have also been seen eating stems and seeds of these shrubs. The leaves are a good source of protein and the stems and leaves have been found to contain a high amount of calcium.


Cultivation

Many ''Ceanothus'' species are popular ornamental plants for gardens. Dozens of Hybrid (biology), hybrids and cultivars have been selected, such as flexible ceanothus, ''Ceanothus × flexilis'' (''C. cuneatus'' × ''C. prostratus'').


AGM cultivars

The following cultivars and Hybrid (biology)#Hybrid plants, hybrids have gained the Royal Horticultural Society's Award of Garden Merit (): *’Autumnal Blue’ *'Blue Mound' *'Burkwoodii' *'Cascade' *'Concha' *'Dark Star' *'Gloire de Versailles' *'Mystery Blue' *'Perle Rose' *'Puget Blue' *'Skylark' *'Topaze' *'Trewithen Blue' *''C. thyrsifolius'' var. ''repens'' Other cultivars available include:- There are also more cultivars and hybrids of '' Ceanothus arboreus'', ''Ceanothus griseus, Ceanothus griseus horizontalis'' (groundcovers), and ''Ceanothus thyrsiflorus'' in the nursery trade.


Propagation

Plant propagation, Propagation of ceanothus is by seed, following scarification (botany), scarification and stratification (botany), stratification. Seeds are soaked in water for 12 hours followed by chilling at 1 °C for one to three months. It can also sprout from roots and/or stems. Seeds are stored in plant litter in large quantities. It is estimated that there are about two million seeds per acre in forest habitats. Seeds are dispersed propulsively from capsules and, it has been estimated, can remain viable for hundreds of years. In habitat, the seeds of plants in this genus germinate only in response to range fires and forest fires.


Other uses

Native Americans used the dried leaves of this plant as an herbal tea, and early pioneers used the plant as a substitute for black tea. Miwok Indians of California made baskets from Ceanothus branches. ''Ceanothus integerrimus'' has been used by North American tribes to ease childbirth.


Nitrogen fixation

''Ceanothus'' is Actinorhizal plant, actinorhizal, meaning it fixes nitrogen through a symbiotic relationship with ''Frankia.'' Six genera within Rhamnaceae are actinorhizal, but ''Ceanothus'' is the only genus not in the monophyletic tribe Colletieae. This suggests that actinorhizal symbiosis may have Convergent evolution, evolved twice in Rhamnaceae. ''Frankia'' forms Root nodule, nodules on the roots of ''Ceanothus'', converting atmospheric nitrogen () into ammonia () using nitrogenase.


References

{{Taxonbar, from=Q311139 Ceanothus, Rhamnaceae genera Flora of North America Taxa named by Carl Linnaeus Garden plants of North America Drought-tolerant plants Saponaceous plants Flora of California