HOME

TheInfoList



OR:

''Osteospermum moniliferum'' (synonym ''Chrysanthemoides monilifera'') is an evergreen flowering
shrub A shrub or 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 by their multiple ...
or small tree in the daisy family,
Asteraceae Asteraceae () is a large family (biology), family of flowering plants that consists of over 32,000 known species in over 1,900 genera within the Order (biology), order Asterales. The number of species in Asteraceae is rivaled only by the Orchi ...
. It is native to southern Africa, ranging through South Africa and Lesotho to Mozambique and Zimbabwe. Most subspecies have woolly, dull, serrate, oval leaves, but the subspecies ''rotundatum'' has glossy round leaves. Subspecies are known as boneseed and bitou bush in Australasia, or bietou, tick berry, bosluisbessie, or weskusbietou in South Africa. (Archived by ) The plant has become a major environmental weed and invasive species in Australia and New Zealand.


Taxonomy

''Osteospermum moniliferum'' has five recognized subspecies: *''Osteospermum moniliferum'' subsp. ''canescens'' *''Osteospermum moniliferum'' subsp. ''moniliferum'' *''Osteospermum moniliferum'' subsp. ''pisiferum'' *''Osteospermum moniliferum'' subsp. ''rotundatum'' *''Osteospermum moniliferum'' subsp. ''septentrionale'' ''Osteospermum moniliferum'' was first described by
Carl Linnaeus Carl Linnaeus (23 May 1707 – 10 January 1778), also known after ennoblement in 1761 as Carl von Linné,#Blunt, Blunt (2004), p. 171. was a Swedish biologist and physician who formalised binomial nomenclature, the modern system of naming o ...
in 1753. It was given the binomial name ''Chrysanthemoides monilifera'' in 1943 by Nils Tycho Norlindh. It was one of two species in genus ''Chrysanthemoides'', along with ''Chrysanthemoides incana'' (now ''Osteospermum incanum''). The species name ''moniliferum'' comes from the
Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...
, ''monile'', meaning necklace or collar, referring to the shiny fruit arranged around the flowers like a necklace. In
Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...
, ''O. m.'' subsp. ''moniliferum'' is known by the common name 'boneseed', while ''O. m.'' subsp. ''rotundatum'' is known by the common name 'bitou bush'.(Archived by the Wayback Machine
Introduction
Section
123
, , )
In
New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...
subspecies are not distinguished and ''O. moniliferum'' is known simply as 'boneseed'. (Archived by )


Description

Boneseed is a perennial, woody, upright shrub, growing to , (Archived by th
Wayback Machine
although occasionally taller. It is a member of the ''Asteraceae'' (daisy) family and has showy, bright yellow
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 in swirls of 5–8 'petals' (ray florets) up to in diameter. Fruit are berry-like, spherical at around 8 mm in diameter, and turn dark-brown to black with a bone-coloured seed inside of 6–7 mm diameter. Leaves are long by wide, oval tapering to the base with irregularly serrate margins. Bitou bush can be distinguished from boneseed in part due to its more rounded sprawling habit to , less noticeably toothy leaf margins and seeds that are egg-like rather than spherical. Both boneseed and bitou bush hybridise readily, however, so examples of plants demonstrating a fusion of traits is possible. ''O. moniliferum'' has been shown to need pollinators in order to reproduce.


Distribution and habitat

''Osteospermum moniliferum'' occurs naturally in coastal areas of
South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. Its Provinces of South Africa, nine provinces are bounded to the south by of coastline that stretches along the Atlantic O ...
, reaching into
Lesotho Lesotho, formally the Kingdom of Lesotho and formerly known as Basutoland, is a landlocked country in Southern Africa. Entirely surrounded by South Africa, it is the largest of only three sovereign enclave and exclave, enclaves in the world, t ...
,
Zimbabwe file:Zimbabwe, relief map.jpg, upright=1.22, Zimbabwe, relief map Zimbabwe, officially the Republic of Zimbabwe, is a landlocked country in Southeast Africa, between the Zambezi and Limpopo Rivers, bordered by South Africa to the south, Bots ...
, and southern
Mozambique Mozambique, officially the Republic of Mozambique, is a country located in Southeast Africa bordered by the Indian Ocean to the east, Tanzania to the north, Malawi and Zambia to the northwest, Zimbabwe to the west, and Eswatini and South Afr ...
. Subspecies ''rotundatum'' is concentrated along the eastern coast of South Africa from its southern tip through
KwaZulu-Natal KwaZulu-Natal (, also referred to as KZN) is a Provinces of South Africa, province of South Africa that was created in 1994 when the government merged the Zulu people, Zulu bantustan of KwaZulu ("Place of the Zulu" in Zulu language, Zulu) and ...
to southern Mozambique. Subspecies ''moniliferum'' is concentrated around
Cape Town Cape Town is the legislature, legislative capital city, capital of South Africa. It is the country's oldest city and the seat of the Parliament of South Africa. Cape Town is the country's List of municipalities in South Africa, second-largest ...
and the
Cape Peninsula The Cape Peninsula () of South Africa is a generally mountainous peninsula that juts out into the Atlantic Ocean at the south-western extremity of the African continent. At the southern end of the peninsula are Cape Point and the Cape of Good ...
on South Africa's south western coast, where its native
habitat In ecology, habitat refers to the array of resources, biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species' habitat can be seen as the physical manifestation of its ...
s include the Cape Flats Dune Strandveld. Subspecies ''canescens'' is native to Kwazulu-Natal, the Northern Provinces, and Free State of South Africa and to Lesotho. Subspecies ''septentrionale'' is native to Mozambique, Zimbabwe, and the Northern Provinces.


Invasive species


Australia

In Australia, subspecies ''rotundatum'' (bitou bush) has naturalised along the coast of
Queensland Queensland ( , commonly abbreviated as Qld) is a States and territories of Australia, state in northeastern Australia, and is the second-largest and third-most populous state in Australia. It is bordered by the Northern Territory, South Austr ...
and
New South Wales New South Wales (commonly abbreviated as NSW) is a States and territories of Australia, state on the Eastern states of Australia, east coast of :Australia. It borders Queensland to the north, Victoria (state), Victoria to the south, and South ...
, while subspecies ''moniliferum'' (boneseed) has naturalised along and near the coast in parts of Victoria and
South Australia South Australia (commonly abbreviated as SA) is a States and territories of Australia, state in the southern central part of Australia. With a total land area of , it is the fourth-largest of Australia's states and territories by area, which in ...
.


New Zealand

In New Zealand ''O. moniliferum'', which is listed on the National Pest Plant Accord, is common in coastal locations throughout the
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 ...
, and can also be found in the
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 ...
in Nelson City,
Port Hills The Port Hills () are a range of hills in Canterbury Region of New Zealand, so named because they lie between the city of Christchurch and its port at Lyttelton, New Zealand, Lyttelton. They are an eroded remnant of the Banks Peninsula Volcano ...
(
Christchurch Christchurch (; ) is the largest city in the South Island and the List of cities in New Zealand, second-largest city by urban area population in New Zealand. Christchurch has an urban population of , and a metropolitan population of over hal ...
) and the
Otago Peninsula The Otago Peninsula () is a long, hilly indented finger of land that forms the easternmost part of Dunedin, New Zealand. Volcanic in origin, it forms one wall of the eroded valley that now forms Otago Harbour. The peninsula lies south-east of Ot ...
.


Impact

In Australia, ''O. moniliferum'' has been particularly successful in invading natural bushland. In part, this is due to the species' ability to establish on relatively nutrient-poor soils and in areas exposed to salt such as coastlines, as well as the ability of the seeds to germinate readily. Disturbances such as fire can assist ''O. moniliferum'' to spread as the plant produces a large amount of seed that can persist in the soil seed bank for 10 years or more, and this reserve in turn enables the species to quickly recolonize a burnt area. An individual plant can produce 50,000 seeds a year, about 60% of which are viable. Once germinated, seedlings grow vigorously with dense, bushy growth. This lush growth shades out and displaces slower growing native species that might otherwise occupy the same ecological niche. Rapid, vigorous growth also means that ''O. moniliferum'' is capable of flowering and setting seed within 12–18 months, making it extremely persistent even in situations where disturbance or regular management activity is common. Once established, the plant's shallow root system enables it to absorb moisture after light rain before the moisture reaches the roots of more deeply rooted species further limiting opportunities for slower growing species to establish and out-compete ''O. moniliferum'' over time. Furthermore, outside of Southern Africa the plant has few local, indigenous pathogens or predators to control its growth also reducing the potential for gaps to emerge that might provide opportunities for other species to reestablish. The net consequence of ''C. moniliferas growth characteristics is that outside of its natural ecosystem it can ultimately form large, dense, unhealthy stands of a single species with extraordinarily poor biodiversity. The plant can extend its existing range in a variety of ways. Its fruit is attractive to birds, rabbits, other animals and even some insects such as ants, and because seeds are tough and difficult to digest they will often be dispersed in animal droppings. Seeds can also spread on vehicles and equipment, in contaminated soil, in garden waste, along water drainage lines and deliberately by human intervention. ''Osteospermum moniliferum'', unlike many other weed species, is not generally considered to be a problem for agricultural productivity due to its sensitivity to trampling as well as being readily grazed by stock.


Control

''Osteospermum moniliferum'' is potentially susceptible to a range of control strategies, but Burgman and Lindenmayer recommended that the strategy chosen be responsive to the local situation and available resources. Due to its relatively shallow root system, removal by hand is an ideal method of control. Where manual removal is impractical, many common herbicides can be used, in which case the herbicide is commonly applied directly to the wood of the plant via a cut notch, or at the end of a pruned stump. Mechanical removal of ''O. moniliferum'' by tractor or other machinery can also be effective, but that process can be extremely indiscriminate, and is only recommended in areas of poor environmental values and minimal erosion risk. Another way of tackling an infestation is the use of controlled burns, but there are risks associated with that method. Principally, ''O. moniliferum'' has higher moisture levels than many Australian indigenous species so, for burns to be effective, a burn of higher than normal intensity is required. That can, in turn, have a detrimental impact on indigenous vegetation which has evolved in response to more frequent, lower-intensity fires. Furthermore, fire can trigger re-germination from the extensive ''O. moniliferum'' seed bank, potentially worsening the situation. However, if a program is implemented to monitor and control ''C. monilifera'' seedlings following the burn and emerging ''O. moniliferum'' seedlings are removed, burning can be extremely effective at exhausting the seed bank and minimising the chances of re-infestation. Various methods of biological control have been attempted, particularly the introduction of insects which are natural enemies of ''O. moniliferum'', such as the bitou tip moth ('' Comostolopsis germana'') and bitou seed fly ('' Mesoclanis polana''). Although they have had some success in controlling bitou bush (ssp. ''rotundatum'') in Australia, to date they have not had similar success in combating boneseed (ssp. ''moniliferum''). In a study carried out by researchers at the University of New England and published in 2017, it was found that a serious error was made with the introduction of biological control agents into Australia for ''C. moniliferum'' ssp. ''rotundatum''. Bitou seed fly (''Mesoclanis polana'') was introduced based on the naive belief that it is a natural enemy of ''O. moniliferum.'' After reviewing many hours of video footage of bitou bush flowers in Northern NSW, researchers at the School of Ecosystem Management found that ''Mesoclanis polana'' is actually the most frequent pollinator of ''O. moniliferum''. Because ''O. moniliferum'' is a weed of National Significance in Australia, that oversight could potentially be devastating to Australian ecosystems. Much like the introduction of the cane toad to control the population of cane beetles, such a discovery is an important reminder about the importance of thoroughly researching biological control agents before introducing them into new ecosystems.


References


External links

* * {{Taxonbar, from1=Q21876051, from2=Q5114539 Calenduleae Flora of the Cape Provinces Flora of Lesotho Flora of Mozambique Flora of South Africa Flora of Zimbabwe Fynbos Trees of South Africa Plants described in 1753 Taxa named by Carl Linnaeus