Infestation through insects and fungi

1. Animal wood vermin

Animal wood vermin are distinguished between forest insects or fresh wood insects and timber-vermin or vermin on stocked timber. Fresh wood insects attack the "living tree" or the logs just chopped. Whereas timber vermin attack only processed wood.

The most important timber vermin are: beetles like rodents (Anobium), Xylophaga (Hylotrupes) and sapwood beeltes (Lyctus).

Timber trade may be confronted with the following fresh wood vermin: wood wasp (sirex), or the timber bark beetle (Lineatus) and different bark beetles - the may erode small channels in the timber or they are flying insects.

2. Fungi discoloring or destroying wood

Besides insects there are also fungi that destroy fresh or processed timber enormous. These fungi appear especially trough inadequate storage, too high humidity or if timber is sheeted with constant contact to earth for example: jambs.

Fungi can neither be associated to the botanical nor animal group. It is a single group with a very complicated anatomy and a much more complicated systematic. We decide basically between two groups: fungi that discolour or destroy wood.

Quelle: Gesamtverband Deutscher Holzhandel / German Timber Trade Federation

Fungi like mildew do not destroy timber but they discolour. Mostly there are species like penicillium and aspergillus that are known from food sector.

Blueness fungi

Blueness fungi do not destroy wood, but they live of the substance of content of the timber beam. The fungi hyphen makes the wood appearing blue. Blueness does mostly attack softwood especially pine. The blue or grey discoloration and blotches do mostly appear in sapwood. If timber dries slowly you can observe this change in colour. Quiet often you find it on non-barked pines that are slowly drying in forest (log blueness) and contain a lot of humidity about months. Same thing may happen on stocking area if wood does not dry fast enough (lumber blueness). Even processed wood for example lacquered window frames can be attacked by blueness fungi - re-humidification of wood trough damage of paintwork (coating blueness). This problem can be avoided while using contrarious-blueness grounding. All three types of blueness are caused by special types of blueness fungi.

Red Strips

Sprouce is mostly attacked by red stripes. It appears on chopped softwood and arises if logs are stocked incorrect. Discoloration, red stripes, moves from superficies surface and front-end of timber to the interior. In the beginning this discoloration does not influence the technical resistance.

Quelle: Gesamtverband Deutscher Holzhandel / German Timber Trade Federation