Blue spruce trees are susceptible to an infectious needle disease caused by the fungus Rhizosphaera. The disease, referred to as Rhizosphaera needle cast, is the most common problem seen on blue spruce samples that are submitted to the Plant Disease Clinic.

How do you treat blue spruce disease?

  1. Make one application in spring or early summer when the new needles have grown to half their mature length.
  2. Make a second application 3 to 4 weeks later.

What kills blue spruce trees?

By far the most common complaint of cultivated blue spruces is needle cast disease, mostly that caused by the fungus Rhizospaera kalkhoffii. It infects young needles and overwinters on living or recently killed foliage. During the growing season, the spores spread to other branches, or other trees, by splashing water.

Can a dying blue spruce be saved?

When you detect some of the symptoms early, you can sometimes save your spruce trees. However, you need professional help to treat some of the diseases that kill spruce trees. On the other hand, if the trees can’t be saved, you can replace them with a different kind.

How do you revive a dying blue spruce?

  1. Prune away dead branches, twigs, and infected areas of the tree.
  2. Remove fallen foliage and destroy it (burn it). …
  3. Apply a fungicide to the tree after removing signs of the infection.
  4. Deep water the tree once per week to help it recover from the stress.

How do you treat blue spruce Cytospora canker?

Management: There is no known cure for cytospora canker. Fungicide treatments are not recommended. The Davey Institute recommends maintaining the health and vitality of susceptible trees to manage the disease; healthy trees are less susceptible to cytospora canker.

When do you spray fungicide on Blue Spruce?

Protecting new growth as it emerges is very important. For best effectiveness, fungicides should be applied when the emerging needles are half elongated (1/2 to 2 inches in length). Needle cast diseases can be effectively controlled with fungicides containing chlorothalonil.

Why is my Colorado blue spruce losing its needles?

The Colorado Blue Spruce often loses its rigid needles after wet seasons. The Rhizosphaera fungus, which thrives in the wet conditions, leads to the needle loss as it takes hold of the spruce. … A common symptom of Needle Cast disease is the needles changing color from green to violet and then brown.

What is the lifespan of a blue spruce tree?

Growth and Yield- Blue spruce is apparently a long-lived tree, surviving up to 600 years or more. Diameter growth is slow; trees 10 to 13 cm (4 to 5 in) in d.b.h. may be 125 to 135 years old; at 46 to 56 cm (18 to 22 in), they may be 275 to 350 years of age (84).

What kills the tops of spruce trees?

White pine weevil damage Larvae of the white pine weevil kill the terminal leader and the top two to four years of growth on many varieties of spruce, as well as white and Scotch pine trees.

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What does Cytospora canker look like?

What does Cytospora canker look like? Cytospora canker usually first appears on lower branches and progresses up the tree. Individual upper branches may show symptoms as well. Needles on infected branches turn purple, then brown and die.

Why are my spruce trees dying from the bottom up?

In drought-like conditions, evergreens may have trouble getting enough water to all their needles. As a result, bottom needles die to help hydrate the rest of the tree. This problem is easy to fix! If the tree’s soil is dry to the touch, give it extra water through summer’s dry spells.

What diseases do spruce trees get?

Rhizosphaera. Probably the most common problem affecting spruce trees is a fungal disease known as Rhizosphaera Needle Cast. This disease can affect most species of spruce, but is especially problematic on Colorado Blue Spruce.

Can you save a dying spruce tree?

Your evergreen tree will only need to be maintained by correctively pruning the damaged, diseased, or dead branches in the tree. Branches that have become damaged, diseased, or have died will need to be pruned so that a new leader of the branch can be established.

Will blue spruce branches grow back?

Generally, spruce trees will regrow as long as buds are available, but pine trees pruned past the last set of needles on a branch will not.

Is my spruce tree dead?

If it’s pliable and bends without breaking, it’s still alive; but if it snaps easily, it’s dead. For the scratch test, use your fingernail to scratch the outer bark of a stem. If the underlying tissue is green, it’s still alive; but if you continue to see brown tissue, that part of the stem is dead.

What is the best fungicide for evergreens?

We use propiconazole or thiophanate methyl or a combination of the two. Fungicide injections using propiconazole can also give good control. Infected needles and leaves are the main source for re-infection of the new plant foliage.

How do you treat fungus on a spruce tree?

  1. Prune out severely affected branches.
  2. Rake up and dispose of fallen needles.
  3. Begin treatment with a registered fungicide in spring at half-needle elongation. …
  4. Deep root water during periods of drought.
  5. Fertilize with Arbor Green PRO to invigorate plant growth.

How do you apply fungicide to Blue Spruce?

It is imperative that you treat the entire tree next spring with the chlorothalonil fungicide just after bud break and before needles are half elongated. A second treatment should be applied 3 weeks after the initial treatment.

What does canker fungus look like?

Cankers are usually oval to elongate, but can vary considerably in size and shape. Typically, they appear as localized, sunken, slightly discolored, brown-to-reddish lesions on the bark of trunks and branches, or as injured areas on smaller twigs.

How do you treat botryosphaeria?

If caught early, localized botryosphaeria canker on plants can be cut out and the entire plant saved. In the winter or very early spring before bud break, prune any branches or canes back to unaffected tissues and immediately dispose of infected debris.

How do you treat nectria cankers?

There is no cure for Nectria canker. Remove smaller branch cankers by pruning six to eight inches below the canker. Disinfect pruning tools after each cut by dipping them for at least 30 seconds in a 10% bleach solution or alcohol (spray disinfectants that contain at least 70% alcohol can also be used).

Are blue spruce trees Hardy?

Colorado Blue Spruce Planting Guide Colorado blue spruce grows best in a sunny location with moist, well-drained, fertile soil. It tolerates dry wind and can adapt to dry soil. The tree is hardy in USDA plant hardiness zones 3 through 7.

Why do my evergreen trees keep dying?

The extreme rains many areas have had in the past two years have led to rotting roots, as most needled evergreens don’t tolerate wet soil for long. Sometimes rotting takes months to become apparent, which explains why trees seem to mysteriously die the spring or summer after a rainy year.

Is spruce in the pine family?

Spruce belongs to the genus of coniferous evergreen trees of the pine family. There are about 40 species.

Will spruce tree needles grow back?

These voracious eaters strip needles from spruce, and those needles will NEVER grow back. … If your spruce is under attack DO NOT PRUNE the stripped branches. The bud at the tip is still alive, and will produce new needles next Spring which will disguise the damage.

How do you keep a blue spruce healthy?

Light and Water Needs. Colorado blue spruce thrives in full sun but also grows in partial shade. Once established, the tree needs a medium amount of water, with a deep soaking every two or three weeks. Even though the tree likes the soil to remain moist, especially while it’s still young, it’s also tolerant of drought.

Why is my spruce dying from the top down?

Pine trees dying from the top down is common, though definitely not a good sign. This condition is referred to as dieback. It may be caused by a number of things, including fungal disease, insect infestation, or harsh weather conditions.

How do you treat a Rhizosphaera needle cast?

Consider treating affected trees with fungicides containing copper as the active ingredient (e.g., Bordeaux mixture) or chlorothalonil. Treatments will not cure existing infections, but can prevent additional infections. Apply treatments every three to four weeks starting as new needles emerge in the spring.

What trees are affected by Cytospora canker?

Cytospora canker disease generally attacks spruces, especially Colorado blue and Norway varieties, as well as peach trees, Douglas firs or hemlock trees. What is cytospora canker? It is a destructive disease caused by the fungus Leucostoma kunzei that disfigures and can even kill vulnerable trees.

Should you trim bottom branches of blue spruce?

Eliminate branches growing in an undesirable direction by cutting them close to the trunk. Trimming bottom branches of blue spruce creates a neater appearance, and makes it easier to reach underneath the tree to rake or apply mulch.