Bijlsma, R.J., J. den Ouden & H.N. Siebel, 2009, Oude eikenbossen: nieuwe inzichten en kansen voor het beheer., in: De Levende Natuur, 110, 2
- Author : Bijlsma, R.J., J. den Ouden & H.N. Siebel
- Year : 2009
- Title English : Old oak woods: new insights and opportunities
- Journal/Series : De Levende Natuur
- Volume Number (ANNUAL: Counting Volumes of the Year shown above) : 2
- Volume Number (CONSECUTIVE: Counting all Volumes of this Journal ever published) : 110
- Pages : 77-82
- Abstract in English : Two Natura 2000 woodland types occur on dry, acid soils in the Netherlands, namely Atlantic acidophilous beech forests with Ilex and sometimes Taxus in the shrub layer (H9120) and Old acidophilous oak woods with Quercus robur on sandy plains (H9190). The former occurs on relatively rich, loamy soils, the latter on the most infertile, sandy soils. The distinction between them is complicated by the fact that most old oak woods are former coppice on loamy soils. These forests are now invaded by beech. On the other hand, both beech and holly encroach upon nutrient poor cover sands and drift sands as well. Holly is a common garden escape and is spreading rapidly in all kinds of woodlands. In order to clarify the distinction between the two types, their definitions, based on vegetation types, have been supplemented by soil and historical characteristics. Beech-oak forests (H9120) can only occur on non-podzolised, loamy soils, boulder clay, old river clay or acidic loess. Old oak woods (H9190) can be found only on podzolised, non-loamy soils or drift sands. Particular woodlands of both types must be present on the first topographical map of the Netherlands of about 1850 as (degraded) woodland or must have an age of at least 100 years. This corresponds to the EC-description of Beech-oak forests that mentions several characteristic ancient woodland vascular plant species. As a consequence of the augmented definition, Beech-oak forests (H9120) are ancient woodlands in the usual sense. They occur close to settlements, are often surrounded by banks and ditches, have pits (loam, iron, gravel), veteran trees or coppice stools and are cut through by old roads and tracks. Bracken (Pteridium aquilinum) often dominates the herb layer. Other ancient woodland species are Maianthemum bifolium and Oxalis acetosella. Several species with persistent seed banks are characteristic as well, such as Hypericum pulchrum. Old oak woods (H9190), on the other hand, occur in the periphery of (former) heathlands or drift sands. They show relief, are often bordered by ridges of drift sand and lack banks and old roads. The herb layer is dominated by Vaccinium myrtillus. North-facing slopes contain northerly species such as Trientalis europaeus and the moss Dicranum majus. The augmented definitions of both Natura 2000 types emphasize differences in geomorphology and topography. This opens opportunities for management. Old oaks woods can be considered as parts of heathland-woodland gradients where openness and conditions for the natural regeneration of oak are maintained by grazing. Beech-oak forests can occur in the upper, more base rich part of the same gradient or as ancient woodlands in larger afforestations. Here, management can focus on veteran trees, coarse dead wood, gap dynamics and natural rejuvenation of beech and holly.