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eech dIseases aNd PesTs<br />
Wallon region<br />
The Walloon beech forest was subjected to a severe insect attack by bark beetles beginning in<br />
autumn 1999 and located throughout the Ar<strong>de</strong>nnes area and to a lesser extent in Gaume. The<br />
main factor that had increased insect pressure seems to be an intense and unusual cold period in<br />
November 1998. Beech bark had been badly injured, allowing xylophagous insects a wi<strong>de</strong> entrance<br />
door. The prece<strong>de</strong>d relative warm period could explain why bark was not acclimatized for frost.<br />
The bark beetles involved were Trypo<strong>de</strong>ndron domesticum Er. and Trypo<strong>de</strong>ndron signatum Er.<br />
Injuries caused by insects were also colonized by fungi. Moreover, ethanol produced by injured<br />
tissues attracted more and more bark beetles. As a result, 11% of beech were infested in 2001<br />
and 5% in 2002 (these numbers do not take into account damaged trees removed earlier). It was<br />
estimated that a volume of 2,000,000 m³ of beech wood has been damaged between 1999 and<br />
2005 (Huart, Ron<strong>de</strong>ux 2001, Huart et al. 2003) 5,6 . Currently, less attacks by bark beetles were<br />
observed, however beech has still the highest rate of <strong>de</strong>foliation in Wallonia (Laurent, Lecomte<br />
2006) .<br />
Flemish region<br />
In Flan<strong>de</strong>rs, diseases and pests do not constitute a major problem. Infections by Nectria ditissima<br />
and N. coccinea and attacks by Rhynchaenus fagi and Apiognomonia errabunda are recor<strong>de</strong>d only<br />
occasionally.<br />
euroPeaN beech GeNe PooL PreservaTIoN aNd coNservaTIoN<br />
oN NaTIoNaL LeveL<br />
For the last ten years, a major effort has been ma<strong>de</strong> to increase the number of seed stands of different<br />
hardwood species. Today, the results are sufficient for beech to meet the regeneration needs of<br />
foresters. Nevertheless, these selections are not directly linked to a general conservation purpose but<br />
are mainly done to ensure good timber production potential for the future.<br />
More specifically, the concept of forest reserves has been <strong>de</strong>veloped since 19 3. Currently, eight forest<br />
reserves with a total area of 244 ha have been registered. They generally comprise special ecological<br />
sites including beech and oaks.<br />
Conservation ex situ was also un<strong>de</strong>rtaken using provenance/progeny trials. In the 1950s, different<br />
tests were established to study genetic variability in beech at different levels (individual, population,<br />
ecological type, provenance). These tests, mainly limited to Belgian populations, completed by<br />
observations in natural forests, show an important variability between populations for different<br />
characteristics such as flushing, morphology of leaves and growth. In addition, Belgium took part in<br />
an international provenance trial in 1988 establishing one site in Paliseul where 4 provenances were<br />
compared. These different trials should give more basic information to elaborate a complete longterm<br />
conservation program (Jacques, De Cuyper 2003) 8 .<br />
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