From the Declaration of the Republic through to contemporary times
Following the destruction of the vegetative covering that the Hunting Grounds of Mafra experienced during World War One, there came about an increase in concern over the state of the forest.
In 1939, José Maria de Carvalho wrote a report commissioned by the Director of the Forestry and Agricultural Services that concluded that the Hunting Grounds were in a fairly poor state with the species prevailing listed as maritime (Pinus pinaster) and stone pines (Pinus pinea), eucalyptus (Eucalyptus globulus) and London plane (Platanus x hispanica).
The cork oaks (Quercus suber) were all stripped bare and hindered by the close proximity of eucalyptuses. This report also refers to the existence of but a few cases of the Portuguese oak before closing with the recommendation that “the National Hunting Grounds of Mafra need an almost complete replanting”. As from 1939, the second and third hunting ground sections were placed in the care of the Forestry Service.
In 1951, Saldanha reported that the Portuguese oak (Quercus faginea) and the cork oak (Quercus suber) were already then well represented with the latter no longer subject to having their cork harvested in a practice that has remained in effect through to contemporary times.
The changes in the distribution of the most characteristic tree species since the 1940s were the following:
The maritime pine (Pinus pinaster) proved the species with the widest spread in 1939, and having in 2003, thus prior to the fire, an incidence ranging from 80 to 160 trees per hectare.
Presently, this species is concentrated in a single forest (Baroque) with around 80 to 100 trees per hectare;
The stone pine (Pinus pinea) was on the decline in 1939 but made a well paced recovery and in 2003 there was a species density of between 80 and 160 trees per hectare and concentrated above all into two major areas (the Chanquinha and Tojeira Pine Forests).
Presently, this species is found throughout the two forests mentioned above and its recovery is proving especially robust in Chanquinha courtesy of a strong protection campaign of natural regeneration.
The Eucalyptus (Eucalyptus globulus), which had been spreading ever since its introduction in the early 20th century, had only a small scale population in 1939 and had all but disappeared by 1951. From that point onwards, this species experienced rapid growth and, in 2003, covered an 89 hectare area.
At the moment, the grounds still contain around 32 hectares of eucalyptus.
However, the forestry management policy ongoing seeks to eradicate or control to the greatest possible extent the presence of this species and now remaining only on the outer limits of the grounds.
The five existing plots are due for felling over their respective life cycle before then undergoing complete replacement by indigenous species (oaks and cork oaks) in a process taking place over the next two decades.
The National Hunting Grounds of Mafra also include other tree species despite having already all but disappearing in the meanwhile and including the sweet chestnut (Castanea sativa) and the holm oak (Quercus ilex).
Others have not only survived, such as the wild olive (Olea europaea var. sylvestris) and the common hawthorn (Crataegus monogyna), but also in the wake of the large fire in 2003 repopulated large areas within the framework of the preventive silviculture plan favouring the black poplar (Populus nigra) the white poplar (Populus alba), the field elm (Ulmus minor), the grey willow (Salix atrocinerea), ashes (Fraxinus excelsior and Fraxinus angustifolia), the Portuguese oak (Quercus faginea) and the cork oak (Quercus suber).
In addition to the arboreal species detailed above, these grounds also contain a reasonable number of arbustive species with some of them having grown to an arboreal size by 2003.
The forestry management practices implemented by the Cooperative have as a rule sought to control these within the framework of preventing another major forest fire.
Correspondingly, we still continue to find around 15 arbustive species with a predominance of heathers (Erica lusitanica), gorses (Ulex jussiaei), the pistachio tree (Pistacia lentiscus), the kermes oak (Quercus coccifera), the flax-leaved daphne (Daphne gnidium), among others.
“Adding to this diversity, there are also over two hundred recorded vascular species in addition to an important set of lichens and bryophytes species.
A still unpublished study of the Hunting Grounds, carried out by Manuela Sim-Sim, recorded eight species of lichen and five species of bryophytes on the barks of stone oaks in just two plots” (Rego, 2006).
REFERENCE: Rego, F.C. (2006). Tapada de Mafra – Uma história natural. General Directorate of Forestry Resources, Lisbon, 83 pp.