Kauri (Agathis australis)

Kauri (Agathis australis) is a coniferous tree found in the northern districts of New Zealand’s North Island. It is the largest (by volume) but not tallest species of tree in the country, standing up to 50m tall in the emergent layer above the forest’s main canopy. The tree has smooth bark and small oval leaves. Other common names to distinguish A. australis from other members of the genus are southern kauri and New Zealand kauri.

Though kauri are among the most ancient trees in the world, they have developed a unique niche in the forest. With their novel soil interaction and regeneration pattern they are able to compete with the more recently evolved and faster growing angiosperms. Because it is such a conspicuous species, forest containing kauri is generally known as kauri forest, though kauri need not be the most abundant tree. In the warmer northern climate, kauri forests have a higher species richness than others found further south.

Taxonomy:

Kingdom : Plantae
Division : Pinophyta
Class : Pinopsida
Order : Pinales
Family : Araucariaceae
Genus : Agathis
Species : Agathis australis

Pronunciation/Meaning:

• Agathis (AG-ath-iss) - From the Greek, meaning a ball of thread, referring to the catkin on the female trees.
• australis (aw-STRAL-iss) - Of or from the south, or Australia.

Common Names:

• Kauri, Southern Kauri, New Zealand Kauri

Links:

• Conifers.org - Kauri
• Te Ara : The Encyclopedia of New Zealand - Kauri
• New Zealand : Dept. of Conservation - Kauri

Image Courtesy of Tim Waters.

Natal Flame Bush (Alberta magna)

Natal Flame Bush (Alberta magna) is a very impressive indigenous shrub or tree, especially when in flower or fruit. Alberta magna is not only treasured by tree collectors and gardeners for its beauty, but also because it is a protected tree in the family Rubiaceae.

At maturity it has grey, rough bark on the stems, the branches are green or brown. The crown of shiny, evergreen foliage makes a foil for the large sprays of brilliant red, tubular flowers which form at the end of the branches in late summer/autumn (February-June). Individual flowers are about 2.5 cm long and are bright red with a hairy calyx. They are followed by small, ribbed fruit with large scarlet “wings” formed from the elongated calyx lobes. These remain colourful for a long time.

Leaves are simple and oppositely arranged. They are 7.5-13 cm long and up to about 5 cm broad, oblong or oval. The leaf margins are untoothed and rolled inwards. The leaves are glossy dark green above and paler below, with a yellowish midrib. Lateral veins are sometimes conspicuous on the underside of the leaf.

The Natal Flame Bush is spectacular but rather difficult to grow. The bark of this tree is used in traditional medicine, but the wood of Alberta magna is almost useless. It breaks readily, hence the common name “breekhout”.

Taxonomy:

Kingdom : Plantae
Division : Magnoliophyta
Class : Magnoliopsida
Order : Gentianales
Family : Rubiaceae
Genus : Alberta
Species : Alberta magna

Pronunciation/Meaning:

• Alberta (al-BER-tah) - Named after Albertus Magnus (Graf von Bollstädt), a German philosopher of the 13th century.
• magna (MAG-na) - From the Latin, meaning great or large.

Common Names:

• Natal Flame Bush, Breekhout.

Links:

• Plants Africa - Natal Flame Bush
• Top Tropicals - Natal Flame Bush
• ZipCodeZoo - Natal Flame Bush

Image Courtesy of Tim Waters.