Aloes and Lilies of Ethiopia and Eritrea

18 ALOES AND LILIES OF ETHIOPIA
(A. bussei, A. drepanolobium), Balanites, Com miphora,
Euphorbia (E. awashensis, E. monacantha, E. burgeri,
E. cryptocaulis E. gymnocalycioides, all of which are
endemic), and Aloe species. The ground cover is rich
in sub shrubs, including species of Acalypha, Barleria,
and Aerva. The soils are commonly sandy, derived from
Jurassic and Cretaceous limestone and other sedimentary
rocks.
This vegetation type occurs in the northern, eastern,
central and southern parts of Ethiopia, and eastern and
northern parts of Eritrea between 400 and 1800(­1900)
m. It is particularly characteristic of extensive areas south
and east of the Eastern Ethiopian and Eritrean highlands
and the western part of the Afar floristic region.
This vegetation type is particularly rich in Aloes and
other lilies including quite a few endemic or near endemic
Aloe species such as A. calidophila, A. ellenbeckii, A.
gilbertii, A. friisii, A. retrospiciens, A. mcloughlinii, A.
pirottae, A. otallensis (Aloaceae); Ammocharis tinneana
(Amaryllidaceae); Anthericum neghellense (endemic),
Chlorophytum pterocarpum (endemic), C. somaliense and
C. zavattarii (all in Anthericaceae); Asparagus aridicola,
A. leptocladodius, A. scaberulus (Asparagaceae); Bulbine
abyssinica (Asphodelaceae); Dracaena ellenbeckiana
(Dracaenaceae) and Ledebouria kirkii (Hyacinthaceae).
This vegetation subtype is marked in dusty pink colour
(Fig. 5) and is represented by an example as shown in
Fig. 7.
Subtype 2b. Acacia wooded grassland of the Rift Valley
(ACB/RF)
The Acacia wooded grasslands of the Rift Valley consist
of a tree stratum mainly or almost entirely with species
of Acacia over a grass stratum. It is located between the
northern, species­poor part of the Acacia-Commiphora
bushland in the western part of the Afar florisic region
and the southern, species rich part of the Acacia-
Commiphora bushland in the southern and eastern
Ethiopian lowlands, but with the absence of members of
the genus Commiphora. Important characteristic species
include species of Acacia (A. etbaica, A. seyal, A. albida,
A. tortilis, A. senegal, etc.; Croton (C. dichogamus)
and Euphorbia (E. candelabrum). The grasses belong
mainly to the genera Hyparrhenia, Heteropogon, Setaria,
Sporobolus and Panicum.