Thanks once again to Jim, aka J.G. in S.F.@Flickr of San Francisco, California for sharing today’s images (original image 1 | original image 2 | BPotD Flickr Pool). This entry concludes our first series celebrating the International Year of Biodiversity. The next series, on the topic of “Sports and Biodiversity”, will start sometime mid-February.
Silver tree (the epithet argenteum means “silver”) or witteboom is native to the Cape Province of South Africa. As should be evident from the second photograph in particular, reflective silvery hairs covering the surfaces of the leaves are responsible for the common name and epithet. The Protea Atlas Project has this explanation for the hairs on the leaves of Leucadendron argenteum: “…[the] thousands of hairs which cover the leaf…protect the plant from desiccation and herbivory. The intensity of the sheen [of the leaves] varies with temperature and is most pronounced in hot, dry weather when the hairs lie flat on the leaves…During wet weather the hairs stand more erect…and the leaves are relatively drab.”
Leucadendron argenteum is considered vulnerable by the IUCN Red List, noting that remaining populations of the species are threatened by the development of Cape Town, too-infrequent fires, alien invasive species and clearing of land for tree plantations. Fortunately, the largest population of the species is protected within the land maintained by Kirstenbosch National Botanical Garden, allowing for management and monitoring.
An excellent description of this species, including its local distribution, the origin of its name and other historical information, and use in cultivation can be read on Plantzafrica: Leucadendron argenteum.