State Forest Service recommendations for harvesting spruce stands.

Forest owners should be aware that several measures must be followed when harvesting spruce stands to avoid encouraging the proliferation of the European spruce bark beetle.

1. Most importantly, felling operations in spruce stands or coniferous stands bordering at-risk spruce stands must be completed by the beginning of April, and timber must be removed from the forest by mid-April.

2. We also recommend clearing all green spruces windthrown or broken by the wind this winter from the forest by 15 April.

3) Between 1 April and 1 September, it is not recommended to carry out thinning or sanitary selective logging in spruce stands older than 50 years (except in cases where the spruce stands are compact and isolated, and are located no closer than 100 m from other mature spruce stands – such stands may be clear-felled in one go).

Although the proliferation of the European spruce bark beetle in Latvia was not as massive as expected last year, this does not mean that vigilance can be reduced this year, as it is impossible to predict what the situation might become, given that the intensity of this pest's proliferation is highly dependent on weather conditions.

It is important for every forest owner to be aware of the threat posed by the most dangerous pest for spruce stands – the European spruce bark beetle (Ips typographus). The European spruce bark beetle is considered the most aggressive forest pest, attacking and destroying not only weakened or over-mature spruces, but also perfectly healthy trees if they have proliferated in large numbers. Most often, the bark beetle proliferates intensely after windthrow, but it can also infest otherwise weakened spruce stands, for example, if the trees have been damaged by fire, their roots have been flooded for a long time, or the trees have been exposed to excessive moisture or moisture deficit. Spruce stands aged approximately 50 years and older are considered at-risk stands, as thicker trees are more suitable for bark beetle development. This pest can also be found in spruce logging residues thicker than 12 cm, but to breed successfully, the bark beetle needs spruce trunks thicker than 20 cm. Dry trees do not pose a risk of bark beetle proliferation. Spruces with peeling bark but green needles have already been abandoned by bark beetles and can be considered dry trees.

If an owner does not manage to harvest their spruce stands by 1 April, it would be safer to postpone these works until autumn. If the basal area of the stand is not below the minimum, the felling of dry and windthrown trees can be carried out by submitting a notification to the VMD forestry office.

More information: Andis Purs, Head of the Forest and Environmental Protection Division, VMD (tel. 67222820)