The operations relating to the A5 action were performed with direct sampling in the forest by creating 22 circular test areas. This to gather data to study the current and evolutionary conditions of the forest. In each test area, the dendrometric data of the adult plants and the Renewal Index were also detected.
The survey has confirmed the presence of two different sub-formations in the Wood of Palo Laziale. A "high Mediterranean forest" dominated by Quercus cerris, Q. pubescens, Q. ilex, Fraxinus oxycarpa. These trees have variable heights (between 10 and 15 m) and estimated variable ages from 20 to 80 years (diameters between 10 and 55 cm). In comparison with the survey performed in 2008, it is now observed a decrease in frequency in the major represented classes due to the forest dieback but, luckily, even an increase from the lower classes from 5 cm to 15 cm. The wood characterized by "low Mediterranean forest" has remained entirely unchanged compared to the previous situation. Just noticed a slight increase in the size of trees and a quite exclusive dominance of Phyllirea spp. (Phyllirea angustifolia) with little tree renewal due to excessive shade. In the mattoral strip (habitat 5230*) the presence of laurel (Laurus nobilis) still prevails.
The forest ecosystem is in recovery (see images below). The data analysis show an important renewal of the wood as demonstrated by the significant increase of the Renewal Index. From the previous survey, it has increased from 106.45 cm to 220 cm. There is also an increase in biodiversity due to the lack of artificial selection of humans. The process is expected to continue like this with an affirmation of the original native oak species (Q. cerris, Q.ilex, Q.pubescens) but also of ashes (Fraxinus oxycarpa).
Renovation of oak trees.
Renovation of ash trees.