Quercus rotundifolia Lam.
Quercus ilex auct., incl. Q. ilex L. subsp. ballota (Desf.) Samp.
Eng.: Holm oak, holly oak. Spa.: Encina, carrasca. Fre.: Chêne vert, yeuse. Ara.: Ballut lakhdar, kherkhach. Tam.: Kerruch, tassaft, tasafet, acherit, uchlef, akhlij, ahlidj, aharch, akerruch, adem, adema, asaf, uasaj, iten, abellutt, azidhan, abuhu, adren, taswklet, abedjud, kechrid.
Evergreen tree, monoecious, robust, up to 25 m in height and even taller, but usually not exceeding 20 m, with rounded or ovoid shape. Trunk straight or somewhat tortuous, up to 2 m in diameter, with hard bark, brown-ashen, fissured. Branches erect in dense forests; extended and horizontal in cleared areas. Branchlets densely white-tomentose. Leaves [2-8(12) × 1-4(6) cm)], alternate, evergreen, highly variable in shape and margin —orbicular to oblong-lanceolate with ± serrated margin, sometimes entire—, coriaceous, dark green ± bright on the upper side and whitish-tomentose on the underside, with tomentose petiole 1-10 mm. Male flowers in yellow and pendant catkins, 2.5-8 cm, very numerous. Female flowers solitary or grouped in 2-7, upright on the leaf axils. Fruit (the acorn) an ovoid to longly ellipsoid achene, 15-35(40) × 8-18 mm, with chestnut-black nut and cupule with ovate or ovate-oblong scales, imbricate and± applied.
Flowering:
April to May.
Fruiting:
October to December.
Habitat:
On all types of terrain, from near sea level to high mountains (the upper limit is reached in the central High Atlas, about 2,900 m). In semiarid to humid bioclimate, on thermomediterranean to supramediterranean floors.
Distribution:
Western Mediterranean region. In North Africa it grows in almost all areas of Mediterranean climate of Morocco, Algeria, Tunisia and Libya (Akhdar Massif), from the Mediterranean to the Saharan Atlas and the Anti-Atlas (inclusive). It seems absent completely, at least currently, in the high steppic Algerian-Moroccan plateaux located between the Tellian Atlas and Saharan Atlas. Its southern boundary is located in the mountains of Ifni (SW Morocco).
Observations:
The great morphological variability of this species has given rise to different views on its independence from Quercus ilex L., in many cases being considered as a subspecies of the latter. Nonetheless, it seems now accepted that Q. ilex, a more mesophilic species, is not present in North Africa. Q. ilex has leaves with 7-14 pairs of secondary veins, petiole up to 10 mm and ± bitter acorns, with cupule 7-10 × 10-15 mm, while Q. rotundifolia has 5-8 pairs of secondary veins, shorter petiole 6-8 mm and generally sweeter acorns (the sweetest and most palatable of the genus), with larger cupule (9-14 × 14-20 mm).
This is undoubtedly the species with the greatest forestry value in North Africa, both from an ecological and economical perspective. It has great ecological value for being a colonising species of large areas, where other trees would struggle to flourish; for the excellent biologically rich soil it creates when its leaves, fruit and wood decompose; and finally for the high nutritional value of its leaves and fruits, that support a large and diverse community of animal species. It great economical value has always been based on the extraordinary quality of its wood, hard and resistant to rot, that has been widely used since ancient times for domestic fire and charcoal. The foliage and acorns, as well as the pastures in holm oak forests have always been greatly appreciated and exploited in farming. The holm oak forests are also home to several species of great hunting value. In conclusion the holm oak forests have been the leading provider of food and energy resources in North Africa for millennia.
However, the main value of holm oak forests is the fundamental role they play in the creation and retention of soil and moisture, constituting the most effective tool to combat erosion and desertification N of the Sahara.
Reforestation is still perfectly possible in most of the large areas of the holm oak’s potential area, currently deforested and threatened by erosion. However, where drought conditions and/or lack of soil no longer allow the successful direct and traditional reintroduction of the species, this could still be achieved both in the medium and long term. To achieve this, the following is needed: native seeds; suitable and timely techniques of soil preparation (without grooves or terraces, without an aligned arrangement, and without the removal of existing natural vegetation); protection of seedlings with opaque tubes to shield them from winter frost, summer high sun radiation, drought and small herbivores (these tubes should be exchanged for larger ones every 2-3 years to allow the tree to grow quickly upwards). The process should be completed with the further replanting of cultivation rows and 2 small summer irrigations helping the trees during the first 5 years. About 10 years later, or when sheep, goats and other ungulates can no longer reach eat the leaves of the lower ¼ of the plant, the tubes can be permanently removed. A landscape full of tubes, increasing in size (about 50 × 200 cm in the final years), may not be very attractive aesthetically, but what used to be a thicket or steppe will emerge again as a young oak forest in just 10 years.
Conservation status:
A common and widely distributed species, not considered threatened. Currently, it has not been assessed at a global level in the IUCN Red List of Threatened Species.