Monthly Archives: November 2016

Old Man’s Beard (Usnea)

Usnea is a genus of mostly pale grayish-green fruticose lichens that grow like leafless mini-shrubs or tassels anchored on bark or twigs. The genus is in the family Parmeliaceae. It grows all over the world including here on Sibuya Game Reserve.

Members of the genus are commonly called old man’s beard, or beard lichen.  It resembles Evernia, which is also called tree moss.

Ecology

Like other lichens, Usnea often grows on sick or dying trees due to the pre-existing loss of canopy leaves, allowing for greater photosynthesis by the lichen’s algae; this leads some gardeners to mistakenly blame the lichen for the tree’s leaf loss and illness.

Usnea is very sensitive to air pollution, especially sulfur dioxide.  Under bad conditions they may grow no larger than a few millimetres, if they survive at all. Where the air is unpolluted, they can grow to 10–20 cm long. It can sometimes be used as a bioindicator, because it tends to only grow in those regions where the air is clean, and of high quality.

Medical claims

According to Paul Bergner, Author of Medical Herbalism. “The usnic acid in usnea is effective against gram positive bacteria such as streptococcus and staphylococcus, making usnea a valuable addition to herbal formulas for sore throats and skin infections. It is also effective against a bacterium that commonly causes pneumonia.

Usnea

Pavetta Lanceolata

Weeping bride’s bush or Christmas bush. In full flower, this bush (pavetta lanceolata), looks like a bride adorned in pure white, full of expectations and hope for a long and happy life, hence the common name.  The alternative common name is also apt as these bushes are in full flower during Christmas time.

Family

Rubiaceae (gardenia family, katjiepiering-familie)

Common Names

weeping bride’s bush, bridal bush, Christmas bush ( Eng. ); treurbruidsbos, bruidsbos (Afr.); umhleza, ilitoba, umgonogono, umphonyana (Xhosa); igololembuzi, umdleza (Zulu); mufhanza, tshituku ( Venda )

Description

Pavetta lanceolata is an evergreen tree or shrub, up to 5(7) m high, regularly decussately branched (opposite pair at right angles to next pair). The bark is greyish white.

Distribution and habitat

Pavetta lanceolata is fairly common in the summer rainfall areas of South Africa, in Limpopo, Mpumalanga, Swaziland, KwaZulu-Natal and the Eastern Cape. It also occurs in southern Mozambique. It often grows in association with other bushes in bush clumps, on forest margins and river banks, and can be found in abundance on Sibuya.

Pavetta Lanceolata

The sweet-smelling Weeping Bride’s Bush (Pavetta) is in flower all over the Reserve at the moment – a gorgeous sight and a delight to the bees!