About common spruce
The common spruce grows throughout Europe but is most common in Central and Northern Europe. It is one of the most important forest trees in Scandinavia. The tree has shallow roots and is therefore subject to stormfall. In optimal conditions, the tree will be up to 40 m high. The common spruce can take shade, and a spruce forest is also characterised by the dark, shady forest floor. The short needles are green, stiff and pointed.
Frøslev uses common spruce from Central and Northern Sweden and from Finland where growth conditions are optimal. The trees are slow-growing, and the quality is therefore the best. We ONLY use certified common spruce from sustainable forestry.
Common spruce is widely used in the construction industry for e.g. timber, planks and boards.
The common spruce is characterised by the bright whitish/yellowish sapwood. The core of the tree, called the heartwood, does not differ significantly in colour, and there is no division between heartwood and sapwood in spruce. In contrast, spruce has a special wood structure that causes closed cells when the spruce is dry. The closed cells in the sapwood of the common spruce make it difficult to impregnate the wood. It is also difficult for water to penetrate the wood which helps protect it. Heartwood is not naturally protected and cannot tolerate seeping water.
Although the wood contains less resin than Scotch pine, there are often visible resin pockets with liquid resin.
The branches are in levels with smaller lateral branches in between. A spruce board is therefore characterised by smaller pin knots between the large knots. The knots are round with a star shape in the middle.
Processing and protection
Common spruce is easy to process with the right equipment and is dressed at Frøslev into the requested profiles and battens etc.
Spruce up to 25 mm thick can be impregnated according to NTR grade SPRUCE and protected against i.a. mildew and blue rot. Spruce thicker than this cannot be impregnated due to the closed cell structure.
Spruce should not be used in direct contact with soil and brick/concrete as it is not possible, as already mentioned, to impregnate all the way through, and this is the exact area with the largest risk of rot and fungal attacks. The durability of spruce can be extended through a treatment with a pigmented surface treatment.
In the open air, covered and protected from water, the common spruce is very durable.
To the greatest extent possible, all wood must be protected by 'structural protection' which means that you plan and build in such a way that the wood is ventilated and water is drained off so that the tree can dry out.
Wood is a natural material and will eventually turn grey. It is a good idea to protect the wood with suitable wood preservatives when dry - either with flat paint finish or transparent wood preservatives.
The extra ...
Did you know that the common spruce is often referred to as "the true" Christmas tree? In old Christmas tales, the common spruce is most often mentioned. The branches point upward and form a beautiful Christmas tree although the needles are prickly.