H. mucronata is a very variable species, often even at varietal level. One of the few constant characters is the fact that the leaves are soft , incurved and slightly pellucid, with translucent margins and keel.
Var. mucronata occurs from the Barrydale area to north of Oudtshoorn.
All pictures were taken at the same spot within Barrydale itself: the first five on 8 Aug. 2017 (late winter/early spring), the last two on 28 Jan. 2016 (midsummer).
Densely branched bushes of this variety, up to a meter tall and to more than a meter in diameter, occur from Fianarantsoa in the central highlands of Madagascar to Tulear in the southwest and Beloha in the south; in the highlands they are locally abundant.
They grow in thin soil on granite, gneiss and limestone rocks, often in the shade of other bushes.
The plants are variable in the size of the stems and leaves as well as the flowers.
On average the leaves are 30 x 4 cm, grey-green with reddish tinge, without markings.
The inflorescence is to 50 cm long, undivided or with 2-4 branches; the flowers are coral-red with pale red tips.
For many years, I have known A. brevifolia to be one of South Africa’s smallest Aloes. It is common in cultivation, but up to last month, I had never seen a plant in the wild. So, when someone gave me directions to a locality he had visited a few days before, I did not wait long to go there, especially because it was in the middle of the flowering season.
It was easy to drive up to a place from where I could see the plants growing on a steep slope. But between the car and the slope, there was a little stream and a lot of dead and live shrubs, so it took a lot of time and effort to come near enough to the plants to get some useful pictures. When I saw them from nearby, I was most surprised by their size, as they were over 3 times bigger than the biggest A. brevifolia I had ever seen before.
On digging into the literature, I found the following information:
Aloe brevifolia has 3 varieties: brevifolia, postgenita and depressa.
Var. brevifolia forms dense colonies of small rosettes. These are about 8 cm in diameter, with 30-40 leaves up to 6 cm long and 2 cm wide. This is by far the most common form in cultivation.
Var. depressa has open rosettes up to 30 cm in diameter; solitary or up to 3. The leaves number about 60, 12-15 cm long x 6 cm wide.
Var. postgenita is intermediate between the two others.
In all three, the inflorescence is about 60 cm tall, with 4 cm long flowers in shades of red (sometimes yellow). Flowering time is October to December.
The species as a whole, occurs in the Western Cape, from Caledon to Cape Agulhas. Var. depressa seems to be known only from the site referred to above.
Over a period of hundreds of years, a great part of the original forest vegetation of Madagascar’s Central Plateau has been destroyed by annual burning.
The resulting savannah-like grasslands are very poor in species. A few succulents can survive the fires, either because they have very thick and fleshy leaves, e.g. the subject of this post, or because they hide underground (such as geophytic Euphorbias, see Euphorbia primulifolia).
A. macroclada is an impressive plant with its leaves up to a meter long and 17-22 cm wide at the base. In winter, the stemless rosettes are adorned with (usually single) inflorescences which in old specimens may be up to 2.5m tall. The many flowers are 2-2.5 cm long and 2 cm wide at the mouth.
It is probably the most widely distributed of the Madagascan Aloes, from 200 km north of Antananarivo to Fort Dauphin in the far south, usually at altitudes between 1200 and 1500 m.
Based on genetic research, in 2013 Ronell Klopper and Gideon Smith created the genus Aloidendron to accommodate 6 species of tree aloes, including Aloe dichotoma.
The plants form trees with a rounded crown, with stems to 1 m in diameter at the base and usually 3-4 m tall (sometimes up to 9 m).
The bark on the trunk peels lengthwise, forming large scales with hard and razor-sharp edges. The leaves are about 30 cm long and 5 cm wide at their base.
In winter (May-August), the flowers appear; they are pollinated by starlings, sunbirds, weaver birds and white-eyes.
From the Brandberg Massif in Namibia to Upington, Kenhardt and the Nieuwoudtville area in South Africa, the species forms a conspicuous component 0f the landscape. The plants occur in open sites, usually in rocky terrain but also in flats.
Depending on the area, rainfall (between 50 and 300 mm per year) may occur in either summer or winter.
Both the scientific and the vernacular name (Orange River Aloe) refer to its occurrence along the Orange River (from Grootderm in the west to Keimoes in the east). It is also plentiful in the Warmbad area of Namibia. The plants are usually found in steep rocky places and are rather variable, depending on the locality.
Usually solitary, the plants are stemless or short-stemmed (up to 1 m tall).
The leaves are 30-40 cm long and 5-8 cm wide near the base, incurved, dull yellowish-green to reddish-brown with numerous longitudinal lines. In young plants they are
copiously spotted on both surfaces, later on they only have some spots on the upper surface. The margins have small, sharp teeth, but otherwise the leaves are unarmed.
The unbranched inflorescences are up to 1.2 m tall and bear flowers from July to September. These are usually yellow to greenish yellow, but in the eastern part of the distribution area sometimes reddish.
This very distinctive species normally produces one single stem up
to 8 m tall and only 10-15 cm thick. Sometimes, plants branch from the base and form large shrubs.
Each stem bears about 25 leaves, up to 90 cm long and grey-green on both sides; the sap is poisonous.
The inflorescences are much-branched, with carmine to reddish-orange flowers.
The species is found in more or less dense bushland and thickets along rivers in
southern Kenya and northern Tanzania at altitudes between 900 and 1500 m.