A healthy spruce is quite decorative and an eye-catcher in your garden. However, if the tree becomes ill or suffers from pests, then it looks very different and soon becomes unattractive.
The spruce gall aphid can be recognized by the unsightly galls
What pests attack spruce trees?
Spruces have very special enemies: bark beetles, spruce gall aphids and Sitka spruce aphids. An infestation is always to be taken very seriously, because the neighboring trees are quickly affected. In addition, there is only a chance of saving your spruce at the beginning of an infestation.
Possible pests in spruce:
- Bark beetles, especially book printers and engravers
- spruce gall aphid
- Sitka spruce aphid or tube spruce aphid
How do I recognize a pest infestation?
You can detect an infestation with the Sitka spruce aphid, also called tube spruce aphid, with the so-called tapping test. Hold a white cloth under a branch and tap it. The lice, if any, then fall clearly visible on the cloth. Now you should act quickly, otherwise your spruce will die.
You will rarely see bark beetles on your spruce, but you will see the tracks of the voracious creatures. The first signs are small brown piles of dust at the base of the tree, the so-called drill dust. If you then take a closer look at the spruce, you might also discover the boreholes. However, these are mostly in the upper part of the crown.
You can recognize the spruce gall louse quite well by the small galls that the louse deposits on the spruce. They are only about five millimeters in size and look like a pineapple.
If the spruce needles turn brown or fall off, then it is almost too late for help.
What can I do against pests?
In the case of a severe infestation with the Sitka spruce aphid or the bark beetle, there is usually nothing you can do to save the tree. It should be felled so that the pests cannot spread to other trees. The same applies to an infestation with bark beetles. Sprays containing paraffin oil help against the spruce gall aphid.
tips
In the near-natural garden, spruce gall aphids are decimated by beneficial insects such as ladybirds and parasitic wasps (€22.99).