Vegetazione a Crambe hispanica L. in Puglia

A phytosociological study of the cenosis to Crambe hispanica L. in Apulia Region is presented. In this Region, the taxon is reported in a critically endangered (CR) status. Two different areas were investigated: the Gargano, in the north of Apulia, and the south-eastern of Murge, in the central part of the Region. On the Gargano the vegetation to C. hispanica prefers the borders of abandoned olive-groves, where it exploits the action of the mitigating effect of the overlooking Varano Lake and the humidity of northern cold winds loaded of rain. Whereas, on the Murge, in the territory of Martina Franca (province of Taranto), where a new and important population of C. hispanica L. was signaled, the taxon locates itself to the borders of cultivated environments (arable lands), where the conditions of greater summer aridity are compensated by the shadowing of few isolated oak trees and, mainly, from reserves of water that accumulate at the bottom of the small "dry stonewalls" (muretti a secco) and/or of the irregular calcareous heaps, resulting from "stone removing work" (spietramento). The vegetation context in which these communities evolved are, in Gargano area, primarily, the scrub vegetation (macchia) referable to Cyclamino repandi-Paliuretum spinae-christi (Biondi 1999), while, in the area of Murge, they reenter in the Quercus troiana Webb subsp. trojana woods areal. The vegetation riliefs and the peculiar environmental features have allowed to ascribe C. hispanica cenosis to a new association of Hordeion leporini: Crambetum hispanicae ass. nova hoc loco. Some strategic devices for in situ maintenance of the taxon and related ecosystems are suggested.