Bastiaens, J., P. van den Bremt, O. Brinkkemper, E. Cosyns, K. Deforce, L. de Keersmaeker, M.J. Kooistra, K.A.H.W. Leenders, R. van Loon, H. Ludwig, N.C.M. (B) Maes, K. vander Mijnsbrugge, G. Tack, H. Vera, A. Zwaenepoel.
Eikenerfgoed in Nederland en Vlaanderen. Eikenbossen en eikenstoven in heden, verleden en toekomst.
Historisch-Geografisch tijdschrift 28 (2010) 115 - 139.
Oude bossen zijn in de Lage Landen schaars geworden. Naar schatting kan minder dan 5% van de totale bosoppervlakte nog tot oude boskernen (ancient woodlands) waar autochtone bomen en struiken voorkomen gerekend worden. In totaal gaat het naar ruwe schatting om slechts circa 15.000 ha. Het betreft veelal oud hakhout of strubbenbos. Met 'autochtoon' worden in het geval van bomen de soorten bedoeld die in onze streken spontaan op eigen kracht gevestigd zijn na de ijstijd, of vóór 1850, met autochtoon plantmateriaal uit de streek aangeplant werden op oude bosplaatsen. In Nederland en in mindere mate in Vlaanderen, nemen de eikenbossen binnen de oude boskernen de belangrijkste plaats in. Hun overleving is met name te danken aan de eeuwenoude hakhout- en middelhoutcultuur en ze bestaan dan ook voornamelijk uit eikenhakhout. Door de veelzijdige producten die de eik leverde, zoals bouwhout, brandhout, schors als looistof voor leer en eikels als veevoer, was deze boomsoort tot aan het begin van de 20e eeuw onmisbaar binnen ons economisch bestel. Een zeer klein percentage van de oude boskernen kan gerekend worden tot opgaand bos (hooghout) of middenbos (middelhout), dat het waardevolle huizenbouw- en scheepshout opleverde en niet in de laatste plaats voer (de eikels) voor varkens. Vermoedelijk is de betekenis van eikels als voedsel voor mensen onderschat. Uit de ijzertijd werden in Amersfoort (Nederland) in een opslagkuil een concentratie van circa 20.000 eikels gevonden en in Boezinge (Vlaanderen) zaten maar liefst circa 69.000 eikels in een put (Deforce et al, 2009). De Romeinen maakten al melding van eikels als voedsel voor mensen (Deforce et al, 2009).
Ancient oak woodlands in the Netherlands and Flanders. Oak woodlands and oak stools in the present, the past and the future
Recent inventories show that old woodland with Pedunculate oak and Sessile
oak constitutes a relatively large part of the ancient woodlands in the
Netherlands and Flanders. These ancient woodlands roughly occupy more than
15,000 ha (37,000 acres). Their distribution and migration routes are now
quite well known, as a result of the increased attention paid to the identification
of native trees and DNA research. The ample presence of oak trees can be
attributed to the wide array of products such as wood, hard and soft bark,
leaves and acorns, that can be obtained from them, all valuable materials
that can be applied in different manners. Old oak habitats owe their preservation
mainly to centuries of coppice culture.
About 7000 B.C. oak trees started to appear among the species present in
the woodlands of the Low Countries. In the Subboreal, the range of trees
found in native woodlands changed due to climate changes, coinciding with
an increased impact of mankind on the land from the Late Neolithic. At
that time period the area occupied by woodlands decreased. In the Middle
Ages the range of trees found in woodlands and the area occupied by woodland,
changed profoundly. The demand for wood and timber increased considerably,
especially for use in the construction of houses, boats, iron smelting-works,
production of charcoal and tanneries. Large-scale deforestation, however,
seems to have started with the land reclamations in the 12th and 13th century.
Recent research shows the complexity of the morphology and genesis of complex
oak stools. In addition to regular coppicing, a number of other factors,
such as livestock and wild animals feeding on young shoots, cutting of
turf or heath, burning, agriculture and drifting sand, play a role in these
processes. The hearts of older oak stools have none or few stems, so establishing
their age is not easy. In some cases historical documents offer accurate
information, as in the case of oak stools growing on the Grebbelinie, a
defence work in the province of Utrecht. It is known the age of these oak
stools measuring about 4.5 m around, is roughly 200 years. Larger occurring
stools, therefore, can be considerably older, depending on their history.
Results of DNA research revealed that many actual oak populations are derived
from the original, autochthonous trees and are distributed in a way corresponding
with the natural migration routes from Spain and Italy followed after the
last Ice Age. These results accentuate the importance of the remaining
ancient woodlands.
Recently, the existence of populations of large oak stools, measuring up
to 25 m around, in Garderen (Netherlands, province of Gelderland), was
explained by assuming a spontaneous germination of acorns in the heather,
followed by feeding and formation of layers of branches. Based on all information
now available, and keeping in mind the complexity of this subject, this
hypothesis seems inaccurate and oversimplified and in need of more research.
No grounds can be found that would justify the extrapolation of this supposition
to other areas with oak stools in the Netherlands and Flanders.
This article presents a reconstruction of the management of oak woodlands
from the Middle Ages onwards, based on archives, maps and actual knowledge
of the remaining ancient woodlands. From the perspectives of cultural history,
autochthonous genetic quality and nature, ancient woodland with oak can
be regarded as valuable vegetation and heritage. Partly because of their
light-loving nature, they are threatened by the modern type of woodland
management. Research and artful integration of all results are needed to
preserve them for the future.