''Crocanthemum'' is a genus of flowering plants in the familyCistaceae. They are native to both North and South America where they are widespread. The common name frostweed relates to the ice crystals which form from sap exuding from cracks near the base of the stem in the late fall.
''Crocanthemum'' are
herbaceous
Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials.
Definitions of "herb" and "herbaceous"
The fourth edition of t ...
subshrubs
A subshrub (Latin ''suffrutex'') or dwarf shrub is a short shrub, and is a woody plant. Prostrate shrub is a related term. "Subshrub" is often used interchangeably with "bush".Jackson, Benjamin, Daydon; A Glossary of Botanic Terms with their Der ...
with alternate leaves. With the exception of species in California, they generally produce two types of flowers: showy, yellow
chasmogamous
Chasmogamy, is a plant reproductive mechanism in which pollination occurs in chasmogamous flowers. Chasmogamous flowers are commonly showy with open petals encircling exposed reproductive parts. Chasmogamous stems from Greek for "open marriage", na ...
(cross-pollinated) produced earlier in the growing season, followed by cleistogamous (self-pollinated) flowers that are smaller and lack petals. All species of ''Crocanthemum'' are fire tolerant and are found in open habitats.
Although the genus was first named in 1836 to encompass New World species of '' Helianthemum'', it generally went unrecognized by taxonomists and its species were included in a broad concept of ''Helianthemum'' throughout much of the 1800s and 1900s. However, phylogenetic studies in 2004 and 2009 indicated that the New World species of ''Helianthemum'' were more closely related to '' Hudsonia'' than Old World ''Helianthemum''. This required the resurrection of the genus ''Crocanthemum'' in order to maintain monophyly.
Species
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Crocanthemum aldersonii
''Crocanthemum'' is a genus of flowering plants in the family Cistaceae. They are native to both North and South America where they are widespread. The common name frostweed relates to the ice crystals which form from sap exuding from cracks near ...
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Crocanthemum arenicola
''Crocanthemum'' is a genus of flowering plants in the family Cistaceae. They are native to both North and South America where they are widespread. The common name frostweed relates to the ice crystals which form from sap exuding from cracks near ...
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Crocanthemum argenteum
''Crocanthemum'' is a genus of flowering plants in the family Cistaceae. They are native to both North and South America where they are widespread. The common name frostweed relates to the ice crystals which form from sap exuding from cracks near ...
Crocanthemum brasiliense
''Crocanthemum'' is a genus of flowering plants in the family Cistaceae. They are native to both North and South America where they are widespread. The common name frostweed relates to the ice crystals which form from sap exuding from cracks near ...
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Crocanthemum canadense
''Helianthemum canadense'' or ''Crocanthemum canadense'' (known as longbranch frostweed, Canada frostweed, frostweed, rock frost, frostplant, or frostwort) is a species of rock-rose (Cistaceae), native to eastern North America
North ...
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Crocanthemum carolinianum
''Crocanthemum'' is a genus of flowering plants in the family Cistaceae. They are native to both North and South America where they are widespread. The common name frostweed relates to the ice crystals which form from sap exuding from cracks near ...
Crocanthemum dumosum
''Crocanthemum dumosum'', common names bushy frostweed and bushy rockrose, is a perennial plant that is native to the United States.
Conservation status
It is listed as endangered in Rhode Island, threatened in New York, a species of special c ...
Crocanthemum greenei
''Crocanthemum greenei'' is a rare species of flowering plant in the rock-rose family known by the common name island rush-rose. It is endemic to the Channel Islands of California, where it grows in the chaparral of the rocky seaside slopes. It ...
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Crocanthemum nashii
''Crocanthemum nashii'' is a species of plant endemic to Florida and other parts of the southeastern United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country p ...
Crocanthemum propinquum
''Helianthemum propinquum'', formerly called ''Crocanthemum propinquum'', common names low frostweed and low rockrose, is a perennial plant that is native to the United States.
Conservation status
It is listed as endangered in Connecticut, and ...
Crocanthemum scoparium
''Crocanthemum scoparium'' is a species of rockrose which is endemic to California.Crocanthemum suffrutescens
''Crocanthemum'' is a genus of flowering plants in the family Cistaceae. They are native to both North and South America where they are widespread. The common name frostweed relates to the ice crystals which form from sap exuding from cracks near ...