The wolfbane is an indigenous shrub found mostly in North Africa but which can also be found in other parts of the Mediterranean particularly in Sicily, Crete, Syria and on some Spanish islands.
In Malta it is usually found in maquis, and garigue habitats. In some localities the wolfbane is very common but as it is not widespread in the Maltese islands it is considered as a scarce plant. I have recently seen it at Għar Lapsi, in the vicinity of Ċirkewwa and at Park tal-Majjistral.
The wolfbane is well adapted for dry habitats. It is a deciduous plant with small thick leaves. The leaves store water while reducing transpiration. But, as in dry habitats storing water in the leaves and reducing water loss is not enough, in summer the wolfbane loses its leaves and goes to sleep. This is in contrast with deciduous plants which live in colder climates which lose their leaves in winter when the ground is froze and because of this they cannot take up water through their roots.
The flowers of the wolfbane are very unusual. To describe the flower accurately one would have to use technical terms which are unintelligible to non-botanists. The flower looks like a five armed star with five curled tendrils growing from the base of the arms. The base colour is pale green which is painted over by a wine colour which varies in amount and intensity from plant to plant.
The flowers appear at the end of autumn and the plant continues to flower until the end of winter. The seeds are also interesting. The seeds are produced in pairs of horn-like structures which break open in summer. Each seed has several fine white silk-like hairs at one end. The threads are very light and easily away by the wind taking the seeds with them. This helps the seed to disperse far and wide and partly explains how this plant can spread quickly from one area to another if the conditions are right.
The hairs attached to the seeds gave rise to the wolfbane’s Maltese name - siġra tal-ħarir which means silk tree.
The wolfbane used to be a protected species as it was a rare plant. Its scarcity was probably due to grazing by sheep and goats but as it is now more common it has been removed from the protected-species list.
This article was published in the Times of Malta on 8 January 2015.