Sasso Malascarpa Nature Reserve was established according to art. 37 of the Regional law no. 86/83. It is one of the most interesting areas in Lombardia under the geologic, geomorphologic, and paleonthological point of view. The protected territory covers an overall area of 196 hectares, partly situated in the Municipality of Canzo, on the left bank of the Ravella stream and it is a property of Demanio Forestale Regionale (the Regional Forest Authority). The rest of the Reserve is situated in the Municipality of Valmadrera, on the left slope of Val Molinata and partially overlaps Parco di interesse sovracomunale di S. Tomaso. The reserve is considered a "partial reserve of geomorphological and landscape interest" and is provided with a management plan approved with a decision of the Regional Board no. 4/52936 of 20th March 1990 which stated the following aims:
The name "Malascarpa" - from the dialect words "sass de la mascarpa" - has doubtful origins. The name of the Reserve might be linked to the meaning of the dialect word "masca" (= witch) and to popular traditions concerning rocks and stones with a particular shape usually associated with negative and dangerous elements.
The territory of Val di Ravella has undergone dramatic changes in the
last decades. The territory was mainly covered by grazing-lands and
sowable lands, while the woodland was marginal and covered not
particularly productive areas.
As it is demonstrated by the
presence of rural buildings at Ia Alpe (Alpe Grasso) and IIIa Alpe
(Alpe Piotti) and of ruins in loc. IIa Alpe (Alpe Betulli), Alpe Alto
and Alpetto, until the end of the 1950s, many families lived in Val
Ravella, devoting themselves to agriculture and cattle breeding.
Moreover, along the road of the Alps you can still recognize the
terraced morphology of the slopes, which were once occupied by sowable
lands.
When people moved downhill, fields were abandoned, and the woodland
could start the progressive conquest of the former agricultural lands.
The
increase in the forest surface was also due to a considerable
reforestation activity, with mainly exotic conifers which have not
always given satisfying results. Currently, the woods cover most of the
surface of the Reserve, except the ridge and the cliff areas.
The origin of the rock formations of the Reserve can be linked to marine sedimentation phenomena. If you observe the Valmadrera area, you might notice a showy tectonic fold of fossil dolomia in Conchodon, including in the rich series of Rhaetic limestone elements rich in fossils, madrepores, white corals looking like small branching trees.
The presence of springs reveals the presence of waters underground: the water deriving from rain, snow, etc. intrudes along the fractures and flows underground until it reaches rainproof layers, along which it tends to be directed up to the emersion.
The mainly carbonate composition of the fractured horizons favors the development of karstic phenomena, which are highlighted on the surface by the characteristic "limestone pavement" situated under Mt. Prasanto; they are vertical furrows in the rock, deep and narrow, shaped by the erosive action of the meteoric waters. In the highest part of the area there are showy white slabs of limestone, called Sasso Malascarpa. The slabs are cut into regularly arranged cubes, given by horizontal and vertical fractures crossing with a right angle. On the surface you can admire a considerable quantity of Conchodon fossils, shells of sea mollusks with two curved valves. In the location "Colma di Val Ravella", the Lombardo Red Ammonite formations are rich in ammonite fossils. In Val Ravella many erratic blocks can be easily found at lower altitudes, like some diorite granites or green serpentine granites which were carried from Valtellina by the sliding glaciers.
In 2008, ERSAF has inaugurated the "Upper Geological Trail", completed with many panels illustrating the main geological and geomorphological features of the Reserve. The itinerary mainly develops along the ridge La Colma - Sasso Malascarpa - Monte Rai, and you can go along it leaving from Terz'Alpe, San Tomaso, or SEC Mountain Hut.
The vegetation is varied: characteristic rock formations, dry grasslands, pastures, shrubs, and woodlands.
Formations living on the rocks can find many large available spaces and
a considerable variety of environmental conditions, colonizing the most
difficult and inaccessible areas. This kind of vegetation belongs to
the phytosociological order of Potentilletalia caulescensis.
In the grasslands and in the former grazing-lands, shrubs are gradually
conquering back the soil with an evolution tending to forest
formations. As far as woods are concerned, the main formation above 850
m of height is the mixed beech tree wood where Whitebeams, Sycamores,
and Ash Trees grow. A little below, oak woods and hop hornbeam woods
can be found. The altimetric limit of both formations varies according
to their exposure.
Hop hornbeam woods form with the beech tree wood wide interpenetration
areas reaching the 1,100 meters on the hottest slopes.
Well-structured high forests are very rare, they are generally made of
Flowering Ash and Hop Hornbeam, originally dominated by coppice,
interrupted by grazing-lands and alternating with artificial
reforestation with Austrian Pine, Spruce Fir, and Larch.
The calcareous nature of the rocks, the steep morphology, and the
geographical position make the territory of the Nature Reserve
interesting from a phytogeographical point of view.
The flora
forming during and after the glaciations was the result of survival and
conquest strategies used by vegetation as an answer to the climatic
changes.
Of particular interest, the species which remained isolated on the
cliffs emerging from the extension of the Alpine glaciers which, in
their period of maximum expansion, reached the edge of the current Po
Plain. After floristic surveys, 136 species typical of the so-called
"flora insubrica" have been catalogued: many of them are endemic
species and are protected by the regional legislation in force.
For some of them, Sasso Malascarpa is the western limit of their
distribution area, and for this reason the whole area is subject to a
particular safeguard.
The most interesting species are: Campanula raineri, Telekia speciosissima, Primula glaucescens, Allium insubricum, Peonia officinalis, and Cytisus emeriflorus.
The census activity involving the Avifauna has led to the
identification of about 40 species, among which the most interesting
ones are the following: the Towny Pipit, the Red-backed Shrike, the
Nightjar, the Black Kite - which uses the reserve as its hunting
territory - and the Rock Partridge - occupying the surrounding areas at
lower altitudes and with better living conditions. The Eagle Owl has
been observed in the area.
The presence of bats is particularly
relevant, since 8 different species live there. Rocky gorges and quiet
woods represent their ideal environment.
As far as the permanent
fauna is concerned, it is rather rare and limited to some specimens of
roe deer and common hare. On the contrary, the wild boar is rapidly
expanding and causes considerable damages to the grass in many parts of
the Reserve.
The mouflon can be found in Moregallo, close to the
Reserve. It was artificially introduced and is now colonizing the
surrounding territory.
The white-clawed crayfish (Austropotamobius pallipes) lives in the stream Ravella.