Marsh pagoda (Mimetes hirtus)

The marsh pagoda is an attractive South African plant with elaborate flower heads and striking colours. With clusters of small flowers, surrounded by bright yellow bracts with red tips, and elongated red styles, the flower heads of the marsh pagoda are extremely conspicuous ⁽³⁾. The tear-shaped green leaves are covered in tufts of minute, fine hairs, and turn rusty brown and crusty on flowering branches, giving the flower head a pineapple-like appearance. The fruit is a hard, greyish single seed, with a fleshy coat and a tough thickening at each end ⁽²⁾.

Also known as

Hairy mimetes, Tall pagoda.

Size

Height: 1 - 2.5 ⁽²⁾

The marsh pagoda is a perennial plant that flowers between May and November ⁽⁵⁾. Birds such as sunbirds, and sugarbirds, are attracted by the sweet, sugar-rich nectar and the brightly coloured bracts and styles, and are the main pollinators. The marsh pagoda also forms an unlikely symbiotic relationship with native ant species, which collect and cache the fallen ripe fruits in underground burrows ^{(2) (3)}. In their nests, the ants consume the fleshy, lipid-rich thickenings covering the seed, but the actual seed with its hard coat, remains intact, and cannot be grasped by ants and ejected from the nests ^{(2) (4)}. The seeds are stimulated to germinate by the changes in temperature, pH and oxygen levels that follow natural fires. This behaviour serves to protect the seeds from rodents, but especially fires, which may kill much of the above ground vegetation, allowing the young plants to thrive in open, less competitive areas, in the fire’s wake ^{(2) (4)}. The marsh pagoda is a relatively short-lived species, and as a result, the plants grow quickly, and maturity may be reached after two or three years of growth, with plants living to a maximum of 15 years ^{(2) (4)}.   

The marsh pagoda is endemic to the Cape Floristic Region, South Africa, and has an extremely limited geographical range, extending from the Cape Peninsula to Agulhas ^{(2) (4)}.   

The marsh pagoda favours lowland riparian habitat, such as marshes, but also grows on mountain peat seeps, up to 400 metres above sea level. Dense stands occur in areas with high groundwater and soil moisture levels, usually adjacent peat wetlands ^{(2) (4)}.

This species has not yet been classified by the IUCN.

The marsh pagoda has a very small range, and as a result of continuing habitat loss, it is listed as Vulnerable on the South African Interim Red Data List ⁽⁶⁾. Substantial areas of marsh pagoda habitat have been lost through urbanisation and habitat conversion for agriculture and orchid plantations. Around urban areas, the natural fires, upon which marsh pagodas are dependant for reproduction, are suppressed, reducing the species’ ability to reproduce, while wetlands may be drained and groundwater extracted. The introduction of non-native plant species also results in increased competition for natural resources, while the invasive Argentine ant (Linepithema humile) can destroy entire populations of the marsh pagoda by eating the lipid seed coat without burying the seed, thereby exposing the fruit to rodents and fires ⁽⁴⁾.The marsh pagoda is also a popular garden plant, and the illegal harvesting of wild plants may be an additional threat ⁽²⁾.  

The marsh pagoda is restricted to the botanically rich habitat of the Cape Floristic Region where conservation is a high priority. Conservation measures currently being undertaken in the region include the restoration of the landscape to its natural state, through the burning and cutting of non-native plants, the purchasing of land to protect against encroaching urban development and agriculture, and the establishment of new protected areas ^{(7) (8)}. In addition, the conservation organisation Fauna and Flora International are coordinating projects that promote ecologically and financially sustainable cultivation of fynbos plants, to provide long-term, community directed protection of this fragile ecosystem ⁽⁸⁾.

For more information on the Cape Floristic Region and its conservation, see:

• Conservation International: Biodiversity Hotspots:
  http://www.biodiversityhotspots.org/xp/hotspots/cape_floristic/

• PlantZ Africa:
  http://www.plantzafrica.com/

Authenticated (09/04/10) by Tony Rebelo, Threatened Species Research Unit, South African National Biodiversity Institute, Kirstenbosch, South Africa.
http://www.sanbi.org/index.php?option=com_content&view=article&id=287&Itemid=617

Bract

Modified leaf at the base of a flower.

Cape Floristic Region

An area occupying about 90,000 square kilometres in South Africa that contains an incredibly high diversity of plant species (around 8,700 species), of which 68 percent are found no where else.

Endemic

A species or taxonomic group that is only found in one particular country or geographic area.

Fynbos

The natural shrubland vegetation occurring in the south-western and southern Cape of South Africa, holding the greatest diversity of plant species in the world. Fynbos is characterised by tall shrubs with large leaves, heath-like shrubs, wiry reed-like plants, and bulbous herbs.

Germinate

The beginning of growth, usually following a period of dormancy and in response to favourable conditions. For example, the sprouting of a seedling from a seed.

Perennial

A plant that normally lives for more than two seasons. After an initial period, the plant produces flowers once a year.

Pollinators

Animals that in the act of visiting a plant’s flowers transfer pollen grains from the stamen (male part of a flower) to the stigma (female part of a flower) of a flowering plant. This usually leads to fertilisation, the development of seeds and, eventually, a new plant.

Riparian

Relating to the banks of watercourses.

Style

An elongated part of the female reproductive organs of a flower that bears the stigma (the receptive area where pollen germinates), usually at its tip.

Symbiotic relationship

Relationship in which two organisms form a close association. The term is now usually used only for associations that benefit both organisms (a mutualism).

1. 1. ZipcodeZoo (January, 2010)
      http://zipcodezoo.com/
   2. PlantZ Africa (January, 2010)
      http://www.plantzafrica.com/
   3. RoyalBotanic Gardens, Kew (January, 2010)
      http://www.kew.org/
   4. Rebelo, T. (2010) Pers. comm.
   5. Protea Atlas Project (January, 2010)
      http://protea.worldonline.co.za/
   6. Interim Red Data List of South African Plant Taxa (January, 2010)
      http://www.sanbi.org/
   7. Cowling, R. and Richardson, D. (1995) Fynbos: South Africa’s unique floral kingdom. Fernwood Press, South Africa.
   8. Fauna and Flora International (January, 2010)
      http://www.fauna-flora.org/fynbos.php