Spruces are relatively rarely susceptible to diseases, pests of spruces appear much more often. White spruce and its varieties are often attacked by the pine spruce, while the spruce spruce pest appears on the blue spruce. See how to recognize diseases and pests of spruce trees and learn about the best ways to protect spruce trees from diseases and pests.
Diseases and pests of spruce - galls on spruce shoots created by the gorse
Diseases of spruce
Spruces quite rarely fall ill.Browning of spruce needlesis most often the result of flooding the root system or rot of the roots and the base of the spruce trunk, i.e. phytophthora.In the latter case, browning and dropping of the needles are accompanied by a brown stain visible at the base of the trunk, which widens along the circumference and progresses towards the apex. Spruce infested with phytophthora should be dug up with the roots and removed, and the place where the plant grew should be decontaminated with fungicide. Spruce or other species sensitive to phytophthora should not be planted again in the same place. Plants growing nearby should be watered preventively with the biological preparation Polywersum WP.
Yellowing andbrowning of the spruce topsand hanging of the shoot tips downwards indicate that the plant was infected with spruce tops plague. Shoots with such symptoms should be cut below the site of symptoms and then the plant should be sprayed with two preparations. First, we use Proplant 722 SL, and after about 2 weeks - Biosept Active.
Sometimes after a close examination (it is worth using a magnifying glass) you can seestains on the spruce needles Initially, they are yellow, with time they turn brown, then black, and finally the entire needle dies. This disease is spruce needle blotch orspruce rashAfter finding it, the entire plant should be sprayed with Topsin M 500 SC. Spraying should be repeated after approx. 10 days. If you do not want to overuse chemicals, you can use Biosept Active for the second spray. In the following years, if the weather is humid, prophylactically spray the plants every 2 weeks with Biosept Active and Biochikol.
Pests of spruce
More than disease, spruce trees are threatenedspruce pestsAmong othersdandelion mothwhose caterpillars are eaten by needles. Young caterpillars are black, while older caterpillars are light or dark brown with a white pattern on the back and blue warts on the sides. The nun moth larvae hatch from April to May and feed on plants until July. They damage many trees and shrubs, but most often spruce and pine trees.In the fight against this pest, sticky bands are placed on spruce trunks, which catch the larvae migrating up the trunk. You can also use insecticide spraying.
Spruce trunks and branches havewhite woolly aphids , i.e.spruce adhesionsThis pest most often attacks spruce varieties white, covering the shoots of these conifers with a white coating and causing the needles to twist. These symptoms are observed from April to June. In order to prevent damage to the spruce trees by the spruce adhesions, the plants are sprayed at the beginning of May with an aphidicide, eg Pirimix Nowy AE or Piromor 500 WG. Gardeners avoiding the use of chemicals in the garden can carry out aphid control with the natural preparation Emulpar 940 EC.
Another aphid attacking spruce trees isspruce mite , which formspineapple, spiny growthscalled galls at the base of the spruce shoots. The pest should be de alt with before the larvae, hidden in the galls, start feeding. Therefore, the inspection of spruce for the presence of galls should be performed already in the early spring and if we find their presence, we spray paraffin oil.For this purpose, you can use the preparations Promanal 60 EC or Treol 770 EC.
Gall on the shoots is also formed byspruce-larch caneIt is fought in the same way as the spruce bastion. The main difference that can be observed between the two guards is that one galls at the base of the shoot and the other at the tip, distorting the young growths.
More photos of galls on spruce shoots and information about fighting spruce on our forum in the topic strange growths on spruce.
Spruce can also feed ongreen spruce aphidAs a result of its existence, you can observe bright streaks andstripes on the needles of spruce , it is often said that the needles become striped. Over time, the needles turn brown and fall off. Fastac 100 EC is recommended to combat this pest, and it is best to spray it in early spring.
Pine spider mite on white spruce 'Conica'
The spider mitecauses mosaic discoloration,needles yellowing and droppingIt is accompanied by characteristic spider webs on conifers. In winter, clusters of wintering amber spider mite eggs can also be found on the bark of spruce shoots. After noticing the wintering spider mite eggs in the early spring, the above-mentioned Promanal 60 EC preparation should be sprayed, and in the growing season - from May to June, spider mite preparations are used, e.g. Karate Zeon 050 CS.
Birds may also be interested in spruces. It is worth knowing that spruce seeds in cones are winter food for many woodpeckers, crossbills and squirrels. In winter, also spruce buds and needles are food for the capercaillies. These birds, however, do not cause much damage to plants and instead of scaring them off, let's be glad that the spruce trees in our gardens can provide them with food in a difficult time for birds, which is winter.
