Acacia, Acacia dealbata
tree of the family Fabaceae, subfamily Mimosoideae
(Silk Tree, Mimosa).
Etymology: "acacia" comes from Greek akis, "spear", because of its thorns. "Mimosa" is its name in the South of France. The name Acacia was spelt with two "c" (" Accacia ") till the end of the XVIIIth century. It is Malherbes, as a defender of the French language, who decided to write Acacia with the only one " c ".
Origin: Australia. The Mimosa is cultivated on the French riviera since 1850.
Species : 600 species, frequent in dry lands, notably in Africa (look below). Acacia retinodes (Water Wattle, Swamp Wattle, Wirilda, Ever-blooming Wattle or Silver Wattle), flowers the whole year round, hence its popular french name, Mimosa quatre saisons (four seasons). Its leaf (to the right) is simple unlike the leaf of the Acacia which is bipinnate.
Habitat: the Mimosa prefers the siliceous soils and grows fast.
Hardiness: the Mimosa is slightly hardy (zone 9). It fears big frost (below -7 °C or 19 °F). The severe frost of 1985 burnt the Mimosas of the South of France. They grew again, from the stump.
In case of prolonged cold, the first symptom is the crazing of the bark. They notice then flow of sap which can remind of the "tears" of the grapevine. This flow has tendency to exhaust the tree, but solidify rather fast.
Maximum size: 25 m in its origin area; 15 m in France.
Bark : smooth, dark grey to reddish-brown. The young stems are covered with a whitish down. |