Vegetation

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…no less than effigies of the gods,
no less than gold and silver images,
they worshiped the majestic trees of the forest.

(Pliny, Naturalis Historia, XII, 1).

And Monterano too has its ancient tree. It may never have been worshipped, but it is sure to have played an important part in the social life of the local community, particularly when working in the fields. The "Quercia della Lega" ("League Oak") as it is known also has a companion, slightly smaller but equally majestic.

Thanks to the effects of the local climate, the vegetation of the Reserve is extremely rich and varied. In particular, the constant flow of moisture from the sea lowers the altitudes at which plants occur (in other words, beech and other species normally found at a higher altitude on hills or even mountains can grow here). Botanists define this association of factors as the "Colchian effect". A fundamental role is also played by microclimate, in other words, the climate of particular habitats such as the gorges where even in the driest of summers there is always cool moist air at the bottom, thanks to the abundance of water, low levels of sun and protection from the wind. In the Nature Reserve, species from Apennine environments such as beech, strictly Mediterranean species such as holm oak, Balkan species such as the European hackberry and "African" species such as the tamarisk can be found growing side by side.

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Woods
 
Considering just the vegetation (the word "vegetation" describes the "community" of plants in a given place or region, how they relate to each other and to the habitat, climate, type of rock, availability of water etc), the woods in the Reserve are predominantly oak woods with turkey oak (Quercus cerris), sessile oak (Quercus petraea) and, in drier sunnier areas, downy oak (Quercus pubescens). There are also other types of woodland, but forest management practices have encouraged reproduction of the turkey oak, used exclusively to produce firewood, to the detriment of other species held to be of little value.  As a result of repeated coppicing (until just a few decades ago often at very short intervals) and overgrazing, the trees have reproduced largely by suckers. More natural forestry management more appropriate for a protected area must, on the other hand, encourage evolution towards mixed coppice and standards or high forest, allowing the plants to regenerate by seed and thus retaining natural variability.
 
The turkey oak woods grow largely on a limestone substratum, preferring dry, moderately acid, poor soils, from the highest altitudes down to the gravely river beds bounding on the alder woods. They also occur at the top of the volcanic gorges near the cultivated land.  From a structural point of view, these are coppiced woods with an average height of 7-10 m (in some cases, the coppice is 25-30 years old). Development of the woodland is heavily dependent on the characteristics and depth of the soil.  On slopes or where the soil cover is thin, numerous species typical of holm oak woods occur (Quercus ilex, Erica arborea, Phillyrea latifolia), while in areas with deeper soil, species typical of the Quercetalia pubescentis association can be found. In addition to turkey oak, downy oak, sessile oak, common hornbeam (Carpinus betulus) and European hop hornbeam (Ostrya carpinifolia), the tree layer also includes another oak, the Italian (or Hungarian) Oak (Quercus frainetto), a native of the Balkans, and the Judas-tree (Cercis siliquastrum).
 
The ground flora includes species such as purple gromwell (Buglossoides purpurocaerulea), lesser asparagus (Asparagus acutifolius), madder (Rubia peregrina), Etruscan honeysuckle (Lonicera etrusca), Russian violet (Viola suavis), bastard balm (MeIittis melissophyllum), black bryony (Tamus communis), European cornel (Cornus mas), field maple (Acer campestre), spindle (Euonymus europea) and common hawthorn (Crataegus monogyna).
 
In the "shelter" of the gorges, there are communities of common hornbeam which grows in the Bicione valley and a number of points along the course of the Mignone (under the old village of Monterano). These often very thick woods prefer dry, acid, sometimes poor soils, but always cooler and more acid than those of the turkey oak woods.
The hornbeam is associated with other broad leafed deciduous trees, a few isolated but important beech trees, several sections of artificial chestnut wood, sycamore (Acer pseudoplatanus), European holly (Ilex aquifolium) and common hazel (Corylus avellana). The presence of beech is particularly important. In central Italy, this species normally occurs above an altitude of 700 metres. Here (as in the other nearby sites of Oriolo, Bassano and Allumiere) however, the environment is cool and moist enough for it to survive, together with holly.  The gorges are the realm of ferns, including the giant of Italian ferns, the royal fern (Osmunda regalis). Together with the very rare deer fern (Blechnum spicant) and other ferns such as the Jersey fern (Anogramma leptophylla), hart’s tongue fern (Phyllitis scolopendrium), soft shield fern (Polystichum setiferum) and common lady fern (Athyrium filix-foemina), this conjures up the atmosphere of ancient forests with a damp cool climate.
 
Particularly picturesque and representative aspects of this type of woodland can be seen along the section of the "Red Itinerary" between the Diosilla waterfall and the confluence of the Palombara and Bicione torrents.
There are also important communities of holm oak (Quercus ilex) growing mainly on the almost vertical slopes dominating the volcanic gorges, but also on limestone terrain. These are typically Mediterranean communities preferring often very poor, not excessively acid soils.  The tree layer is made up almost exclusively of holm oak, accompanied by the less common flowering ash (Fraxinus ornus). Common species in the shrub layer include tree heath (Erica arborea), strawberry tree (Arbutus unedo), mock privet (Phillyrea latifolia), ivy (Hedera helix), butcher’s broom (Ruscus aculeatus) and laurustinus (Viburnum tinus). There is an interesting area of sageleaf rockrose (Cistus salvifolius) garrigue on rocks overlooking the Palombara valley and a population of common juniper (Juniperus communis) near a holm oak wood near the northern boundary of the Reserve.  Where the land is poor and rocks abound, another "oriental" plant is found…  the European hackberry (Celtis australis), a tree of sometimes imposing dimensions whose light coloured trunk reinforced by "buttresses" evokes images of tropical forests.  Magnificent examples can be found on the plateau of Monterano or the wild Greppa della Scalette area.
 
The riparian vegetation along the banks of the Mignone river and other watercourses in the Reserve is of particular importance and afforded special protection as the priority habitat in the Site of Community Importance. It consists of small woods growing on pebble and sand beds where the soils are constantly damp but not covered by water, moderately acid and rich in nutrients deriving from the constant input of plant material brought by the water.  The tree layer is an average 15 m high and the formation is no more than 3-10 m thick along the banks of the Bicione torrent, Mignone river and Rafanello torrent, due to the presence of cultivated land and pastures which exert constant pressure on the relict wetland woods.  The predominant species in the very thin shrub layer are bramble and elm, while the ground flora species most typical of damp habitats are mild water pepper (Polygonum mite), water pepper (Polygonum hydropiper), remote sedge (Carex remota), procumbent marsh wort (Apium nodiflorum), common horsetail (Equisetum arvense), deer fern (Blechnum spicant) and royal fern (Osmunda regalis).
Here, black alder (Alnus glutinosa) dominates supreme, with trees often reaching impressive dimensions.  Rarer are the white and purple willows (Salix alba and Salix purpurea) whose branches stretch from one bank to the other, creating characteristic "tunnels" of great scenic beauty.  There are a few white poplars (Populus alba) and the occasional specimens of tamarisk (Tamarix africana) are particularly interesting. These woods have to cope constantly with the instability of the underlying soil, subject either to erosion or the deposition of debris depending on variations in the flow of the watercourse which, in the case of the Mignone, may vary enormously from season to season, or from one year to the next.
 
Considering just the aquatic vegetation in the strict sense (in other words, the communities growing mainly along the Mignone), this is made up of communities typical of the stony deposits along the banks and small islands in the river (often flooded), characterised by procumbent marsh wort (Apium nodiflorum), water mint (Mentha acquatica) and sweet galingale (Cyperus longus) together with water pepper (Polygonum hydropiper) and water couch grass (Paspalum distichum), together with herbaceous plants typical of shallow-water (7-20 cm) and moderate currents (0.5-0.1 m/s) where there are often continuous populations of hydrophytes such as water cress (Nasturtium officinale) and procumbent marsh wort (Apium nodiflorum). Floating or rooted hydrophytes typical of moderately deep water with no or moderate current also occur in large sections of the river, such as curled pondweed (Potamogeton crispus) and floating pondweed (Potamogeton natans), in places reaching as much as 100% coverage.  On damp banks such as those surrounding the Mercareccia ponds, there are pendulous sedge (Carex pendula), bulrush (Typha latifoglia) and reeds (Juncus sp.), together with floating and rooted plants such as curled pondweed (Potamogeton crispus) and floating pondweed (Potamogeton natans).
It is vital that these populations are completely protected from man’s actions as they are some of the most natural formations in the whole Reserve.  The typical species are all rare or threatened and deserve appropriate conservation measures.

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Scrubland
 
Maltreated but of vital importance, the areas of scrubland consist of mesophile species and, on the sunniest volcanic slopes, expanses of broom (Cytisus scoparius) and the rare and protected glandulous broom (Adenocarpus complicatus). On sometimes steeply sloping outcrops of volcanic rock, the woodland is fringed by tree heath (Erica arborea) scrub an average of 2 m high. This acid-loving Mediterranean-oceanic species is particularly well adapted to fire,  especially resistant to the fire itself and among the first to put out new shoots on the burnt land afterwards.  It is an excellent pioneer, but also encourages repeated fires as it burns extremely rapidly, partly due to the presence of abundant dry branches low to the ground.
In the absence of fire, the heather scrub evolves into holm oak wood, then when the canopy of oak trees shut out the sky, the heather wastes away and dies.
 
On predominantly clay soils, the pastures are dotted with isolated areas of scrub an average of 1.5 m high. Mostly thorny, the main species include blackthorn (Prunus spinosa), common hawthorn (Crataegus monogyna), bramble (Rubus ulmifolius), almond-leafed pear (Pyrus amygdaliformis), dog rose (Rosa canina) and field elm (Ulmus minor).
As well as providing shelter and a breeding ground for large numbers of animals, this vegetation represents the "mantle" of the woods, in other words, the strip of vegetation whose tangle of thorny branches protects from overgrazing, allowing the young trees responsible for expanding the woods to grow through.  It is not uncommon to see isolated downy oaks or other trees surrounded by a small nucleus of typical blackthorn scrub species.
It is precisely the silent work of this "invasive" (as some still define it) scrubland in hill and mountain areas which has enabled woods to recolonise hundreds and thousands of hectares during the last thirty years, to the benefit of society as a whole. This is why they are protected by law.

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Herbaceous plants
 
The west and north-west parts of the Reserve are characterised by open habitats with meadows and pastures of herbaceous plants or scrub, scene of the never-ending battle between woodland and grassland.  When the number of grazing animals drops, the woodland gains the upper hand and vice versa. These habitats are of vital importance, not just economically, but also ecologically, as they are associated with numerous plant and animal species. The latter include mammals such as hares and large birds of prey.
 
On clay soils, the often overgrazed pastures are populated by species such as star thistle (Centaurea calcitrapa), reversed clover (TrifoIium resupinatum), ball clover (Trifolium nigrescens) and corn daisy (Coleostephus myconis), then when the grazing pressure slackens, they begin evolving towards thorny scrub as the bramble (Rubus ulmifolius) proliferates.
 
On clayey soils with lying water, the meadows reach an average height of 30-40 cm, populated with predominantly perennial species such as crested dog’s tail (Cynosurus cristatus), Gaudinia fragilis, Ranunculus velutinus, Oenanthe globulosa and sweet yarrow (Achillea ageratum). This is the habitat where some of the Reserve’s most interesting plants grow, including numerous species and natural hybrids of orchid, concentrated mainly on the marly limestone hill of Monte Angiano. At least 29 species of orchid belonging to 11 genera are found here, together with 4 natural hybrids.
The type of land use (free range grazing of Maremmana breed cattle) keeps the sward short, guaranteeing the survival of uncompetitive species such as many of the Orchidaceae. In addition, the land has not been ploughed or cleared of boulders and stones, thus ensuring the stable environment required for the spread of species with a long life cycle. Pollinating insects are also extremely common in this area, facilitating the insect pollination on which numerous species of orchid largely depend.
The area is one of the most important botanical sites in Lazio and perhaps in Italy and must be preserved at all costs, largely by maintaining existing land use.
The species and hybrids present (observed and monitored through surveys carried out in collaboration with the GIROS Association) include the pyramidal orchid (Anacamptis pyramidalis), long-leaved helleborine (Cephalanthera longifolia), heath spotted orchid (Dactylorhiza maculata), broad helleborine (Epipactis helleborine), bee orchid (Ophrys apifera), Bertoloni’s bee orchid (Ophrys bertolonii), bumblebee orchid (Ophrys bombyliflora), dark bee orchid (Ophrys fusca), late spider orchid (Ophrys holoserica), early spider orchid (Ophrys sphegodes), spider orchid (Ophrys incubacea), Orchis fragrans, Italian orchis (Orchis italica), marsh orchis (Orchis laxiflora), green-winged orchid (Orchis morio), butterfly orchid (Orchis papilionacea), Provence orchis (Orchis provincialis), lady orchid (Orchis purpurea), monkey orchid (Orchis simia), tongue orchid (Serapias lingua), Serapias vomeracea, autumn lady’s tresses (Spiranthes spiralis), together with natural hybrids such as Orchis morio x papilionacea, Orchis laxiflora x fragrans and Orchis simia x italica.
 
The species typical of Mediterranean limestone meadows can be found on rocky outcrops near the bridge over the Mignone and outcrops of marly limestone on Monte Angiano with very poor, arid, acid soils. They include rough clover (Trifolium scabrum), disk trefoil (Hymenocarpus circinnatus), Brachypodium distachyum, Ammoides pusilla, Reichardia picroides and Urospermum dalechampii.
These are plant communities with high diversity, including numerous interesting species which must be protected from high impact transformations (deep ploughing, stone removal, etc.)
One particularly interesting aspect of the herbaceous flora in the Reserve (the term "flora" indicates all the plants in a given area or region of the Earth, irrespective of how they are related to each other and with the environment) is the pioneer velvet bent grass subspecies, Agrostis canina montelucci, found in central Italy where it colonises large areas near solfataras. Here, its high resistance to extremely poor, acid soils, often saturated with highly mineralised water and with emissions of carbon dioxide and hydrogen sulphide, veritable inhospitable deserts for other species, and extraordinarily high resistance to trampling by livestock, enable it to form continuous carpets uninterrupted by the presence of other species.
 
Near the ruined village of Monterano, the most heavily trampled meadows in the whole Reserve are made up of rye grass (Lolium perenne), great plantain (Plantago major) and rough meadow grass (Poa triviaIis), with clumps of stinging nettle (Urtica dioica) near the ruins.  For many, these are just a nuisance to be eliminated, but the numerous butterflies which lay their eggs on this species do not see it quite that way!
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Conservation
 
The Reserve has a number of main strategies for conserving the plants and animals found there:
* maintaining biodiversity by protecting the mosaic of various types of vegetation representing the typical countryside of the Maremma area of Tuscany and Lazio;
* special protection for habitats with important plant species. Of particular importance are the woods in the gorges, of vital importance for their wealth of plants, scenic beauty and role as a shelter and corridor for animals;
* special attention to areas of scrubland, with the aim of encouraging their evolution into woodland and ensuring protection, breeding grounds and a supply of food for a large number of animal species;
* regulation of grazing on grassland and in woods to avoid excessive pressure on less resistant species and soil erosion;
* prevention of fire and restoration of degraded areas.
 
In accordance with forestry legislation, the Reserve promotes the conservation and valorisation of woods of whatever size, degree of coverage and composition. Woods are a natural asset with a vital role to play in maintaining the environmental and hydrogeological balance and safeguarding biodiversity. They also have particular scenic, recreational, didactic and scientific importance. They must therefore be administered in harmony with the principles of sustainable resource management and compatibly with the community’s expectations of well-being.  Forest ecosystems are complex biological systems, in equilibrium with the environment but at the same time constantly evolving towards greater stability and complexity in a typical sequence of:  abandoned field - scrubland - scattered groups of trees and scrub - evolving woodland - mature high forest. This process usually takes about 100-150 years and can be interrupted at any moment by activities such as ploughing, scrub clearance, fires and overgrazing.
 
In the Reserve, woods along the watercourses and in the gorges are given special protection, not least for their vital importance to wildlife. Owners are eligible for compensation to avoid the damage caused by coppicing and measures are implemented to encourage evolution towards high forest, coppicing with standards and reforestation.  Forestry management in both privately owned and publicly owned (Manziana University of Agriculture) woodland is regulated through the issue of authorisations by the Nature Reserve which verifies that the coppicing complies with the planning instruments (forestry plan, forestry improvement plan) and current legislation.  The authorisations incorporate measures to protect forest biodiversity, including the obligation to leave a number of dead trees standing (important for insects, small mammals and woodpeckers), special protection for berry-producing shrubs and trees indispensable for wildlife and action to encourage both specific diversification (trees belonging to different species are left) and structural diversity (with the aim of preserving the natural layers of the wood… ground flora, shrub layer and tree layer).

 

Ultimo aggiornamento: 3.09.2009 (15:37)   Stampa Stampa