Until the 1960s, the use of the forest of Val Porta was intense, anthropic pressure was important and consequently the forests were generally young and with a limited amount of woodland. Afterwards, the strong decrease in agricultural activity and the abandonment of forest use allowed the arboreal vegetation to regain a good part of the territory and to evolve in a natural way, approaching in part the structural and compositional characteristics of the forest at the last stage of its natural succession (climax forest).
Today, forests are generally characterized by natural hillside, mountainous and subalpine area forests, some of which are mature and vigorous. Val Porta is located in the seasonal region defined as “southern boundary alps with sporadic spruce” and is characterized by the following forest formations: the mixed deciduous forests (hilly belt), the beech forests, beech-woods and birch forests (mountain belt), larch forests and high-altitude pioneer woods (subalpine belt).
For each forest formation the following main forest types observed are indicated in italics on the ground.
The beeches
The beech forests are by far the most predominant forest formation up to 1500 - 1600 m a.s.l. on soils that are generally stable and acidified, where the beech (Fagus sylvatica) is at its ecological optimum. In the forest of Lovald, and sporadically on the right slope, there are mature stands with beech trees of considerable dimensions.
Luzulo niveae–Fagetum typicum
Luzulo niveae–Fagetum dryopteridetosum
The fir-beeches
This kind of forest was likely much more common in the past. The only significant trace is present in front of Rienza in the Lovald forest between 1300 - 1500 m a. s. l., with some small stands of silver fir (Abies alba).
Luzulo silvaticae–Abieti–Fagetum calamagrostietosum arundinaceae insubricum
Larch forests
Presence of natural and anthropogenic larch forests. The grazed larch forests of Alpe Stavascio, abandoned decades ago, are characterized by old larches (Larix decidua) of remarkable dimensions, while the larch plantation of Ör Piatt, created in 1898, is dominated by larch trees, accompanied by spruces and beeches.
Rhododendro ferruginei–Laricetum
Adenostylo–Laricetum
Junipero–Laricetum
High altitude pioneer woods
Dominated by green alder or drosa (Alnus viridis) and the rowan (Sorbus aucuparia), these constitute the arboreal cover of the upper belt, with outposts located around 1850 m a.s.l. a few tens of meters from the summit of Sassello.
Alno viridi–Sorbetum aucupariae
Alnetum viridis
The birch forests
Natural birch forests (Betula pendula) on blocks or in the areas abandoned by agriculture.
Corylo–Betuletum su blocchi
Corylo–Betuletum su posizioni zonali
The mixed deciduous forest
Adult and mature stands of mixed broadleaf trees, located at the entrance of Val Porta, with the sporadic presence of chestnut woods. Presence of black alder (Alnus glutinosa) along the path from Colletta to Morasc.
Luzulo niveae–Tilietum
Cruciato glabrae–Quercetum castanosum var. basifila
Arunco–Fraxinetum castanosum
Naturalistic
To safeguard the forest formations and protect the evolutionary dynamics, preserving the genetic heritage (larch, silver fir and beech), and to safeguard and promote the development of spontaneous fauna and flora.
Recreational
To enhance the value of an area with remarkable naturalistic and landscape contents, for people to discover the regenerating effect of the uncontaminated forest on Man.
Educational
To promote environmental education: raise awareness of nature and promote the understanding of the natural evolution of forest environments.
Scientific
To monitor the natural evolution of forest ecosystems, understand the dynamics of spontaneous development of the forest in order to refine methods and techniques of forestry management, especially in protected forests.
Designation
Val Porta Forest Reserve (Riserva forestale Val Porta)
Promoter
Patriziato of Vogorno
Year of institution
2016
Protected area
641 ha
Property conditions
The protected area is located entirely on property of the Patriziato of Vogorno.
Typology
Forest reserve according to the “Concept for the creation of forest reserves in Canton Ticino”.
Management
The wooded area is left entirely to natural evolution except for safety cuts along watercourses and hiking trails.
The Val Porta belongs to the zone of pennidic overlays. The crystalline rocks, metamorphosed during the alpine orogenesis, are mainly paragneiss, minute gneiss and mica schists. Groundwater debris is particularly frequent on the right slope of Val Porta. Rock emerges to a greater extent on the left slope.
The soil typology includes acid brown soils in areas occupied by broadleaf trees and podzolic soils in those occupied by conifers. In general, therefore, there are acid soils with great permeability and a marked presence of rocky skeleton. These types of soil favour a good development of the forest. The important altimetric gradient significantly influences the forest contents of The Val Porta: from Vogorno at 490 m a.s.l it goes up until Pizzo Vogorno, at 2442 m a.s.l. Over a distance of about 5 km one passes from the mixed deciduous forest of the Piedmont strip to the larch forests and alpine grasslands of the upper areas, passing through the beech and fir woods of the intermediate areas. Val Porta has been shaped by the intense action of glaciers and rivers and therefore presents two distinct profiles, with the upper part tending to be characterized, particularly on the upper slopes by the U-shaped glacial form, and the lower part with a V-shaped fluvial connotation.
Val Porta is located in the transition zone between the lake and alpine regions. The main meteorological influences come from the south, which is mainly reflected in the precipitation and temperature regimes. The vegetation period in the hilly area lasts 6 - 7 months (April - October) and in the subalpine zone 4 - 5 months (May - September). Rainfall is abundant and particularly intense during the vegetative period.
Temperatures
Annual average in Vogorno 12 - 13 °C (temperatures must be corrected by 0,6°C for every 100 m of height difference)
Precipitation
Annual average 1800 - 2000 mm