The sugar loaf spruce is a dwarf form of the original species Picea glauca. It bears the cultivar name 'Conica' and is very popular in smaller gardens. Incorrect site conditions and suboptimal care can lead to pest infestation.
Spruce trees are also attacked by pests
coniferous spider mites
Oligonychus ununguis belongs to the spider mites and is also known as the spruce spider mite. The insects can hardly be seen with the naked eye because they reach a maximum size of half a millimeter. Their spider threads, which extend between the needles, are more clearly recognizable.
way of life
Dry and warm weather favors the spread of the plant sap suckers. Mass reproduction quickly occurs in the protected crown area, as the harmful insects can produce up to ten generations per year. Winter eggs survive the cold season at the needle base. They are about 0.1 millimeters in size and have a green-brown to orange-red color. The first mites hatch from the end of April.
damage picture
The sugar loaf spruce appears burned because the needles first turn a dirty grey-green to yellow-grey on the sunny side and finally turn completely brown. They stay on the tree for a while before falling off. Fighting as early as possible before the new leaves sprout is advisable.
You can do this:
- Water and fertilize conifers well during dry periods
- Place potted plants in a cool, semi-shady spot
- Spray an aqueous solution with rapeseed oil on the affected shoots
Sikta spruce aphid
Elatobium abietinum is also known as the spruce tube louse and infests coniferous trees from February or March. The plant sap suckers prefer the darker areas of the crown, so that an affected sugar loaf spruce shows brown needles inside first. As the pest spreads, this browning spreads to the tip of the crown and to the outer crown area. Uncontrolled spread of insect pests can kill trees if they shed excessive foliage.
detect infestation
Hold a sheet of white paper under the affected twigs and tap them off with a broom handle. This way you can see if the plant is infested with lice. Sitka pine lice are green in color and have red eyes that are clearly visible under a magnifying glass.
fight pests
If the infestation is not yet widespread, beneficial insects can help. Ichneumon wasps (€22.99) Lacewings and hoverflies are natural predators and contain the pest populations. In the case of a strong one, natural agents based on rapeseed oil or potash soap, which you spray on all branches in each floor, will help.
Avoid pest infestation
In order to protect sugar loaf spruce from pests, the right choice of location is of great importance. The ornamental shrubs prefer the cooler areas of the garden that allow humid conditions and are not prone to waterlogging. Warm, dry locations, lack of light and over-fertilization are risk factors that favor the spread of pests. Weakened trees are good food for insect pests, so you should take care of them properly.