Trail e ultra trail, maratona, ultramaratona nei magredi a Pordenone - Italy

From the edges of the river beds downstream, a first section can be identified where there isn’t a real structured vegetation. Walking through the gravels, the first “pioneering” plants and the less demanding species are to be observed. Their roots penetrate among stones and sands and, having developed some helpful adaptation behaviours in order to preserve the little humidity at their disposal, they start slowly colonizing the so hostile habitats. Lichens and mosses, above all, take part in the first steps of this difficult process, followed by the presence of thin brushes and herbs which grow in simple stalks and isolated spots.

It is not so uncommon to find mosses in such permeable soils: in order to survive, they just need the presence of a little surface water, at least in spring and autumn time.

The typical plants of the river bed are:

• matted globularia (globularia cordifolia)
• silvery broom (genista sericea).

Mattiola carnica (Foto Vaccher)

The “primitive Magredo”

In this band, the vegetation is discontinuous, but the weft of the turfs and plants with prostrate growth form tends to close the meshes of a net which is getting thicker and thicker until it becomes an arid meadow. The herbs with tough thickness and woody creeping little stalks are called camefite suffruticose.They form vegetation spots and bushes among the stones. Herbs and shrubs spared by the floods have managed to bridle and make the not consolidate gravels steady contributing to the creation of a very thin layer of relatively fertile soil with humus. Typical plants of the “primitive Magredo” are:

• fumana procumbens
• winter heat (erica carnea)
• matted globularia (globularia cordifolia)
• endemic centaurea dichroantha
• alpine avens (dryas octopetala).

Brassica  (Foto Vaccher)

The colonization processes create gradually a continuous pasturage and then a first surface layer of rather mature soil, where the last phase is represented by the ferralitic soil.

In those places where men intervene with light manures and periodical mows, the situation may soon develop and form permanent polyphyto-meadows with the presence of more demanding species and good fodders. The meadows of the “evolved Magredo” remind of what the landscape of the Hungarian Puszta must have been. Typical plants of the “evolved Magredo” are:

• chrysopogon gryllus (grass)
• false oat-grass (arrhenatherum elatius - fodder plant)
• yellow cockscomb (rhinanthus freynii)
• pyramidal orchid (anacamptis pyramidalis).