''Acaena'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of about 60 species of mainly

evergreen In botany, an evergreen is a plant which has Leaf, foliage that remains green and functional throughout the year. This contrasts with deciduous plants, which lose their foliage completely during the winter or dry season. Consisting of many diffe ...

, creeping

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 ...

perennial plants and

subshrub A subshrub (Latin ''suffrutex'') or undershrub is either a small shrub (e.g. prostrate shrubs) or a perennial that is largely herbaceous but slightly woody at the base (e.g. garden pink and florist's chrysanthemum). The term is often interch ...

s in the family

Rosaceae Rosaceae (), the rose family, is a family of flowering plants that includes 4,828 known species in 91 genera. The name is derived from the type genus '' Rosa''. The family includes herbs, shrubs, and trees. Most species are deciduous, but som ...

native Native may refer to: People * '' Jus sanguinis'', nationality by blood * '' Jus soli'', nationality by location of birth * Indigenous peoples, peoples with a set of specific rights based on their historical ties to a particular territory ** Nat ...

mainly to the Southern Hemisphere, notably New Zealand, Australia and South America, but with a few species extending into the Northern Hemisphere, north to Hawaii ('' A. exigua'') and California ('' A. pinnatifida''). The

leaves A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, ...

are alternate, long, and pinnate or nearly so, with 7–21 leaflets. The

flower Flowers, also known as blooms and blossoms, are the reproductive structures of flowering plants ( angiosperms). Typically, they are structured in four circular levels, called whorls, around the end of a stalk. These whorls include: calyx, m ...

s are produced in a tight globose nflorescence in diameter, with no petals. The

fruit In botany, a fruit is the seed-bearing structure in flowering plants (angiosperms) that is formed from the ovary after flowering. Fruits are the means by which angiosperms disseminate their seeds. Edible fruits in particular have long propaga ...

is also a dense ball of many

seed In botany, a seed is a plant structure containing an embryo and stored nutrients in a protective coat called a ''testa''. More generally, the term "seed" means anything that can be Sowing, sown, which may include seed and husk or tuber. Seeds ...

s; in many (but not all) species the seeds bear a barbed arrowhead point, the seedhead forming a burr which attaches itself to animal fur or feathers for dispersal. Several ''Acaena'' species in New Zealand are known by the common name bidibid. The word is written variously ''bidi-bidi'', ''biddy-biddy'', ''biddi-biddi'', ''biddi-bid'' and a number of other variations. These names are the English rendition of the original Māori name of ''piripiri''. The plant is also called the New Zealand burr. The species '' Acaena microphylla'' has gained the

Royal Horticultural Society The Royal Horticultural Society (RHS), founded in 1804 as the Horticultural Society of London, is the UK's leading gardening charity. The RHS promotes horticulture through its five gardens at Wisley (Surrey), Hyde Hall (Essex), Harlow Carr ...

Award of Garden Merit The Award of Garden Merit (AGM) is a long-established award for plants by the British Royal Horticultural Society (RHS). It is based on assessment of the plants' performance under UK growing conditions. It includes the full range of cultivated p ...

Etymology

The generic name ''Acaena'' is derived from the Greek "akaina" (thorn), referring to the spiny

hypanthium In angiosperms, a hypanthium or floral cup is a structure where basal portions of the Sepal, calyx, the petal, corolla, and the stamens form a cup-shaped tube. It is sometimes called a floral tube, a term that is also used for corolla tube and cal ...

Species

Plants of the World Online Plants of the World Online (POWO) is an online taxonomic database published by the Royal Botanic Gardens, Kew. History Following the Convention on Biological Diversity, the Royal Botanic Gardens in Kew launched Plants of the World Online i ...

accepted the following species: *'' Acaena agnipila'' *''

Acaena alpina ''Acaena alpina'' is a Perennial plant, perennial shrub of the genus ''Acaena'' known for its hardiness and durability. ''A. alpina'' is found throughout central Chile and Argentina. It can withstand a wide range of climates, including that of th ...

'' *''

Acaena anserinifolia ''Acaena anserinifolia'', the bidibidi, hutiwai, or piripiri, is a species of plant, endemic to New Zealand. It has been introduced to the UK and Ireland. Bidibidi can be used to make a tea, used by both Māori and Pākehā settlers in New ...

'' *''

Acaena antarctica ''Acaena antarctica'' is a small herbaceous plant in the Rosaceae family native to Argentina, Chile and the Falkland Islands. Taxonomy and naming ''Acaena antarctica'' was first formally described in 1846 by Joseph Dalton Hooker. Kew holds spe ...

'' *''

Acaena argentea ''Acaena'' is a genus of about 60 species of mainly evergreen, creeping herbaceous perennial plants and subshrubs in the family Rosaceae, native mainly to the Southern Hemisphere, notably New Zealand, Australia and South America, but with a fe ...

'' *''

Acaena boliviana ''Acaena'' is a genus of about 60 species of mainly evergreen, creeping herbaceous perennial plants and subshrubs in the family Rosaceae, native mainly to the Southern Hemisphere, notably New Zealand, Australia and South America, but with a fe ...

'' *'' Acaena buchananii'' *'' Acaena caesiiglauca'' – glaucous pirri-pirri-bur *'' Acaena caespitosa'' *'' Acaena confertissima'' *''

Acaena cylindristachya ''Acaena'' is a genus of about 60 species of mainly evergreen, creeping herbaceous perennial plants and subshrubs in the family Rosaceae, native mainly to the Southern Hemisphere, notably New Zealand, Australia and South America, but with a fe ...

'' *'' Acaena dumicola'' (

South Island The South Island ( , 'the waters of Pounamu, Greenstone') is the largest of the three major islands of New Zealand by surface area, the others being the smaller but more populous North Island and Stewart Island. It is bordered to the north by ...

of New Zealand) *'' Acaena echinata'' – sheep's burr *'' Acaena elongata'' *'' Acaena emittens'' (

North Island The North Island ( , 'the fish of Māui', historically New Ulster) is one of the two main islands of New Zealand, islands of New Zealand, separated from the larger but less populous South Island by Cook Strait. With an area of , it is the List ...

of New Zealand) *'' Acaena eupatoria'' *''

Acaena exigua ''Acaena exigua'' is an extinct species of flowering plant in the rose family known by the common name liliwai. It was endemic to Hawaii, where it was known from Kauai and west Maui. It had not been seen or collected since 1957 and was feared ext ...

'' – ''liliwai'' (

Hawaii Hawaii ( ; ) is an island U.S. state, state of the United States, in the Pacific Ocean about southwest of the U.S. mainland. One of the two Non-contiguous United States, non-contiguous U.S. states (along with Alaska), it is the only sta ...

) *'' Acaena fissistipula'' *'' Acaena fuscescens'' *'' Acaena glabra'' *'' Acaena hirsutula'' *'' Acaena inermis'' *'' Acaena integerrima'' *'' Acaena juvenca'' (New Zealand) *'' Acaena latebrosa'' *'' Acaena leptacantha'' *'' Acaena longiscapa'' *''

Acaena lucida ''Acaena lucida'' is a small plant in the Rosaceae family, which is native to southern Chile, southern Argentina and the Falkland Islands. Taxonomy and naming ''Acaena lucida'' was first formally described in 1789 by William Aiton, as ''Ancist ...

'' *'' Acaena macrocephala'' *'' Acaena magellanica'' – greater burnet *'' Acaena masafuerana'' *'' Acaena microphylla'' – New Zealand-bur *'' Acaena minor'' *'' Acaena montana'' *'' Acaena myriophylla'' *''

Acaena novae-zelandiae ''Acaena novae-zelandiae'', commonly known as red bidibid, bidgee-widgee, buzzy and piri-piri bur, is a small Herbaceous plant, herbaceous, prostrate Perennial plant, perennial, native to New Zealand, Australia and New Guinea, of the family Ro ...

'' – red bidibid (New Zealand) *'' Acaena ovalifolia'' *'' Acaena ovina'' *'' Acaena pallida'' – sand bidibid *'' Acaena patagonica'' *'' Acaena pinnatifida'' – Argentinian biddy-biddy *'' Acaena platyacantha'' *''

Acaena poeppigiana ''Acaena'' is a genus of about 60 species of mainly evergreen, prostrate shrub, creeping herbaceous plant, herbaceous perennial plants and subshrubs in the family Rosaceae, native plant, native mainly to the Southern Hemisphere, notably New Zeala ...

'' *'' Acaena profundeincisa'' *'' Acaena pumila'' *''

Acaena rorida ''Acaena rorida'' is a species of mat-forming perennial plant known only from grassy uplands on the Mangaohane Plateau in the northwestern part of the Ruahine Range in the North Island of New Zealand. Within its range, this plant occurs in ar ...

'' (North Island) *'' Acaena saccaticupula'' *'' Acaena sarmentosa'' *'' Acaena sericea'' *'' Acaena splendens'' *'' Acaena stangii'' *'' Acaena stricta'' *'' Acaena subincisa'' *'' Acaena tenera'' – lesser burnet *'' Acaena tesca'' (South Island) *'' Acaena torilicarpa'' *'' Acaena trifida''

Invasive species

Some species have been introduced accidentally to other areas, attached to

sheep Sheep (: sheep) or domestic sheep (''Ovis aries'') are a domesticated, ruminant mammal typically kept as livestock. Although the term ''sheep'' can apply to other species in the genus '' Ovis'', in everyday usage it almost always refers to d ...

wool Wool is the textile fiber obtained from sheep and other mammals, especially goats, rabbits, and camelids. The term may also refer to inorganic materials, such as mineral wool and glass wool, that have some properties similar to animal w ...

, and have become

invasive species An invasive species is an introduced species that harms its new environment. Invasive species adversely affect habitats and bioregions, causing ecological, environmental, and/or economic damage. The term can also be used for native spec ...

. ''

'', one of the bidibids from New Zealand, is the most commonly encountered species in the

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotlan ...

, where it is often abundant on coastal sand dunes, crowding out native vegetation and creating an often painful nuisance with the barbed burrs. In California, '' A. pallida'', ''A. novae-zelandiae'' and '' A. anserinifolia'' are considered serious weeds."Weeds Sorted by Pest Rating"
CFDA.ca.gov

References

External links

Jepson Manual TreatmentUSDA Plants ProfileLandcare Research New Zealand
{{Taxonbar, from=Q1327017 Pantropical flora Rosaceae genera