Just for a change: just pictures and names. Hopefully a measure of inspiration will compensate for the lack of information.
Let’s start with some Crassula’s.
1 C. arborescens ssp. arborescens
2,3 C. barbata ssp. barbata
4 C. mesembryanthoides ssp. mesembryanthoides
5 C. nudicaulis v. platyphylla
6 C. perfoliata var. minor
7,8 C. perforata
In his revision of the genus Crassula (see yesterday’s post), Toelken makes the following remark with regard to the 2 subspecies: “…it is significant that each one can be identified without hesitation. No plants with intermediate characters have been recorded..”
To my mind, there is little doubt that the next picture shows ssp. congesta.
But the plants in the next two ones look like intermediate forms to me.
The last picture was taken just south of Calitzdorp and shows what I think is a hybrid between Crassula congesta ssp. laticephala (which was not found on this particular spot, but does occur in the general area) and C. columnaris (which was growing close by).
In 1985, Volume 14 of the Flora of southern Africa was published, in which H. R. Toelken dealt with the familie Crassulaceae. His description of Crassula congesta starts with the word “Biennials”. In other words, plants that germinate and grow in the first year, and flower and set seeds in the second year, after which they die.
So far so good, but … A couple of years before (1977), “A revision of the genus Crassula in southern Africa” by the same botanist had been published by the Bolus Herbarium. In this publication it is stated that:
“These plants are described as biennials but this is true only under favourable conditions. In the field, the plants often become much older before they flower but usually the whole plant dies after flowering. The plants are usually monocarpic * but regeneration after flowering may sometimes occur, but usually only when the plant has been injured and/or if the terminal inflorescence was cut of”.
* A monocarpic plant flowers only once and then dies after the seeds have ripened.
There are two subspecies:
ssp. congesta, which has leaves that are curved upwards and is found North and Northeast of the Witteberge and
ssp. laticephala, with the leaves curved downwards and occurring Southeast of that mountain range, as far East as Oudtshoorn.
In this post only pictures of the latter subspecies are shown.
H. R. Toelken in his “Revision of the genus Crassula in southern Africa” calls this the most complex subspecies found in C. capitella, which in turn he refers to as a complex species.
The subspecies is widely distributed in the Eastern and Western Cape provinces, Limpopo and southeastern Namibia.
The white or pink flowers are borne in groups along an elongated inflorescence (up to 40 cm tall) and appear between November and March.
In cultivation one normally sees the form shown in the first four pictures.
The photo below shows plants as they are found in and around the Anysberg Nature reserve. They have beautifully marked leaves which are much shorter then one would expect in subsp. thyrsiflora.
As the reserve is on the western border of the distribution area of subsp. capitella, they may belong there, but I will have to see the flowers before being able to properly identify them.
It is probably safe to say that C. alstonii cannot be confused with any other plant species because of its unique appearance. The leaves are arranged in two rows and closely adpressed – at least in nature; in cultivation this is difficult to maintain. Each of the almost spherical rosettes is 2-5 cm in diameter.
The plants are found in northern Namaqualand, from just south of Lekkersing to near Komaggas, where they grow on low, gently sloping hills usually covered with quartzite gravel. This is a rather restricted distribution area, but in some places the plants are quite common.