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ENDANGERED SPECIES OF PELARGONIUM

Wayne Handlos

1   2   3   4   5

1.P. caledonicum* 2.P. curviandrum* 3.P. fergusoniae* 4.P. nephrophyllum* 5.P. ochroleucum*

6   7   8   9   10

6.P. viciifolium  7.P. viciifolium  8.P. petroselinifolium  9.P. petroselinifolium  10.P. appendiculatum

As noted previously, the largest numbers of species of Pelargonium are found in the

southern and western part of South Africa in two vegetation types or biomes: Fynbos

and Succulent Karoo. Many of the species in these biomes are relatively rare or scarce

and grow in very limited areas. As a result any disturbance of the habitat can place these

plants at risk of extinction. The South African flora has been relatively well studied and

the conservation status of many species has been evaluated.

In the case of Pelargonium 34 out of 275 listed taxa (species and other categories such as

subspecies or varieties) are considered of conservation concern. Four species are listed as

CR critically endangered, 11 taxa are considered EN endangered, 11 are considered

vulnerable VU, 5 are considered near threatened NT and 3 species are considered critically

rare found in only one site or location but not currently threatened. No species of Pelargonium

are listed as extinct or possibly extinct.

For comparison, the genus Oxalis in South Africa has about the same number of species as

Pelargonium and they live in similar habitats. Forty-four out of 259 taxa are considered of con-

servation concern. Seven species of Oxalis are listed as extinct or P EX possibly extinct, 1

species is listed as CR critically endangered, 7 are listed as endangered EN, 20 are considered

vulnerable VU, 4 are considered near threatened NT, 5 are critically rare (found in only one site).

The following specific threats have been listed for the various species of Pelargonium: (a) agriculture poses

the greatest threat including wheat cultivation (7 instances), vineyards (7), general agriculture (6), rooibos tea

cultivation (4), potato cultivation (3), citrus orchards (1), deciduous fruit tree orchards (1); (b) overgrazing is

listed in 5 instances; (c) collecting wild plants for medicinal use or hobbyists (4); (d) urban development (4);

(e) mining (3); (f) alien plant invasions (2); (g) ostrich farming (2) . Some taxa are threatened by multiple factors.

For Oxalis, the threats for individual populations include: unspecified crop cultivation and agriculture (10 cases),

wheat cultivation (8), mining (6), urban development (6), overgrazing (5), vineyards (5), rooibos tea cultivation (4),

alien plant invasions (2), citrus orchards (2), unspecified orchards (2), dam development (2), road construction (1),

no reproduction (1), climate change (1). Again, some species face multiple threats.

In South Africa, the threats to all species are ranked as follows: top three habitat loss, habitat degradation

(overgrazing, mismanagement of fire), invasive alien species. Of considerably less threat are harvesting, pollution,

demographic factors (poor breeding, small population size), changes in species dynamics (loss of pollinators or

dispersers), climate change and natural disasters (droughts, floods).

Much detailed information about the South African flora can be found at www.redlist.sanbi.org/ They note that

25.4% of the species/taxa of plants in South Africa are either extinct, threatened or of conservation concern, while

74.6% are not endangered at the moment. In the Western Cape (largely fynbos) there are 10,714 taxa (51.9% of

all South African species) of which 6,655 are endemic. Of these 1,865 are threatened (66.37% of all threatened

South African species). The Northern Cape (largely Succulent Karoo) has 4,845 species (23.5% of all South

African species of plants) of which 1232 are endemic and 387 are threatened (10.5% of all threatened South

African species). The Western Cape has 21extinct taxa, 3 extinct in the wild, 37 critically endangered and possibly

extinct, 290 critically endangered, 619 endangered and 877 vulnerable species and other taxa amongst all families.

No other province or area approaches that level of conservation concern. From another angle, fynbos has 3,188

endemic species of conservation concern, next is the Succulent Karoo with 538 species of conservation concern,

 followed by grasslands with 349 taxa of conservation concern.

RED LIST OF SOUTH AFRICAN THREATENED PELARGONIUMS

P. adriaanii VU         P. appendiculatum EN         P. asarifolium VU         P. attenuatum EN        P. caledonicum CR           

P. chelidonium EN       P. connivens VU              P. crassipes EN          P. curviandrum VU       P. divisifolium NT

P. elandsmontanum Crit. Rare                         P. ellaphieae EN          P. exhibens NT          P. fasciculaceum NT

P. fergusoniae EN       P. heterophyllum CR           P. leptum VU            P. longicaule var. angustipetalum VU

P. nephrophyllum EN    P. nummulifolium Crit. Rare      P. ochroleucum VU       P. petroselinifolium VU     P. plurisectum VU

P. pubipetalum VU      P. reflexum EN                P. reniforme NT          P. sabulosum EN         P. saxatile Crit. Rare

P. sibthorpiifolium CR   P. suburbanum subsp. suburbanum VU                   P. ternifolium NT          P. tripalmatum CR

P. viciifolium EN       P. violiflorum EN               P. reniforme

INTERESTING AND IRRELEVANT ASIDE

What is "rooibos"? Translated from Afrikaans, the word means red bush referring to the color of

the tea brewed from the leaves (and stems) of this plant. The plant Aspalathus linearis is a member

of the bean family, Fabaceae, and produces small yellow sweet-pea-like flowers followed by small pods

containing one or two seeds. The leaves are long and thin hence the name "linearis". The overall

appearance of the plant is that of the European broom, green leaves and stems virtually indistinguish-

able from a distance. The plant is a woody perennial shrub growing to about two meters tall and grows

in acid, sandy soil in areas with winter rainfall and hot dry summers. They are found in the biome

known as "Fynbos". The roots in association with bacteria produce nodules and fix nitrogen. Plants in

plantations are replaced every 5 to 7 years and appear to be a sustainable crop with low demands on

soil nutrients. The seeds are collected by ants and stored underground. The seeds need to be scarified

(the seed coat needs to be mechanically opened) so that water can enter so that germination can occur.

Rooibos tea was brewed traditionally and later adopted by Europeans for use in place of expensive and

imported Asian tea (from Camellia sinensis). In the 20th century, fermentation of the leaves was intro-

duced to more closely simulate Asian tea. The tea is caffeine free and low in tannins though two are

found with antioxidant properties aspalathin and nothofagin. Fresh leaves are high in ascorbic acid

(Vitamin C). Many claims are made but the health benefits of rooibos tea are largely untested. As the

demand for rooibos tea has grown, plantations/fields have been planted to grow this plant for commercial

 quantities of dried, fermented leaves/stems. Rooibos tea was popularized by Mma Ramotswe in the

charming, detective, novel series The No. 1 Ladies Detective Agency by Alexander McCall Smith and the sub-

sequent TV series.

2017, Central Coast Geranium Society (CCGS )