introduction - Ecologia Mediterranea

INFLUENCE OF IVY (HEDERA HELIX L.) ON THE GROWTH OF DOWNY OAK (QUERCUS PUBESCENS s.l.) u
trees showing clear symptoms of decline, such as shoot
withering and progressive crown reduction, can be often
found. Accordingly, in such cases ivy can be considered
a structural parasite (Stevens, 1987).
In order to better understand the nature of the interactions
between this liana and downy oak, an investigation
through aboveground biomass and tree-ring analysis
was carried out. The main goal was to contribute at
improving knowledge about the place and the role of lianas
in forest dynamics, thus providing information that
could be useful in assessing the future forest management
guidelines, above all in protected areas.
METHODS
Study site
The study site is located in the Sicani Mts (37°43’N,
13°31’E), central-western Sicily, Italy (fig. 3). It is included
in the Monte Carcaci Nature Reserve, which was
established in 1997.The landscape is hilly-mountainous,
with a mean elevation of about 700 m a.s.l. The soils are
predominantly Calcic brown soils,Vertic brown soils and
Rock outcrop (Fierotti, 1988), lying on limestones and
clays substrata. According to Brullo et al. (1996), the cli-
ecologia mediterranea, tome 29, fascicule 1, 2003, p. 5-14
Figure 2. Plants of ivy
completely wrapping
the host downy oak crowns.
Just the top of both host trees
(arrows) emerge through
the liana foliage.
mate is meso-Mediterranean sub-humid, with yearly rainfalls
of about 720 mm and mean annual temperature of
13.5 °C.
Figure 3. Localisation of the study site
( Monte Carcaci Nature Reserve).
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