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Publication #ENH-609

Picea glauca: White Spruce1

Edward F. Gilman and Dennis G. Watson2

Introduction

This North American native tree has a fairly broad, pyramidal silhouette when young but matures into a dense, 40 to 60-foot-tall column, 10 to 20 feet high. The short, silver-green needles densely clothe the upright branches making White Spruce ideally suited to use as a hedge or windbreak. Small, 1 to 2.5-inch-long, light brown, pendulous cones decorate the branches throughout the year. The new layers of purplish/grey bark have a soft, silvery sheen which add to the tree's attractiveness as a specimen planting.

Figure 1. 

Young Picea glauca: White Spruce


[Click thumbnail to enlarge.]

General Information

Scientific name: Picea glauca
Pronunciation: PIE-see-uh GLAW-kuh
Common name(s): White Spruce
Family: Pinaceae
USDA hardiness zones: 2A through 6B (Fig. 2)
Origin: native to North America
Invasive potential: little invasive potential
Uses: specimen; screen; Christmas tree
Availability: somewhat available, may have to go out of the region to find the tree

Figure 2. 

Range


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Description

Height: 40 to 60 feet
Spread: 15 to 20 feet
Crown uniformity: symmetrical
Crown shape: pyramidal, columnar
Crown density: dense
Growth rate: moderate
Texture: fine

Foliage

Leaf arrangement: alternate (Fig. 3)
Leaf type: simple
Leaf margin: entire, terminal spine
Leaf shape: needle-like (filiform)
Leaf venation: parallel
Leaf type and persistence: needled evergreen, fragrant, evergreen
Leaf blade length: less than 2 inches
Leaf color: green, blue or blue-green
Fall color: no color change
Fall characteristic: not showy

Figure 3. 

Foliage


[Click thumbnail to enlarge.]

Flower

Flower color: red, yellow
Flower characteristics: not showy

Fruit

Fruit shape: elongated, cone
Fruit length: 1 to 3 inches
Fruit covering: dry or hard
Fruit color: brown
Fruit characteristics: does not attract wildlife; not showy; fruit/leaves not a litter problem

Trunk and Branches

Trunk/bark/branches: branches droop; not showy; typically one trunk; thorns
Pruning requirement: little required
Breakage: resistant
Current year twig color: brown
Current year twig thickness: medium, thick
Wood specific gravity: 0.40

Culture

Light requirement: full sun, partial sun or partial shade
Soil tolerances: clay; sand; loam; acidic; slightly alkaline; well-drained
Drought tolerance: high
Aerosol salt tolerance: low

Other

Roots: not a problem
Winter interest: no
Outstanding tree: yes
Ozone sensitivity: tolerant
Verticillium wilt susceptibility: resistant
Pest resistance: sensitive to pests/diseases

Use and Management

Most often found on stream banks and lake shores, White Spruce should be grown in the landscape on moist or dry soils in full sun or partial shade. Trees which are well-established are quite tolerant of wind, heat, cold, and drought but can also tolerate wet soil for a period of time.

Propagation is by seed or cuttings.

The cultivar `Conica' is a 10 to 15-foot-high dwarf form with soft, blue/green needles and is ideal for container use, particularly at Christmastime.

Pests

Mites, aphids and bagworms are the most common pests.

Two gall commonly attack Spruce. Eastern Spruce gall adelgid forms pineapple like galls at the base of twigs. Galls caused by Cooley's Spruce gall adelgid look like miniature cones at the branch tips. The gall adelgids do not kill trees unless the infestation is heavy. A few galls on a large tree are not serious.

Bagworms make a sack by webbing needles together. Small numbers may be picked off by hand or use Bacillus thuringiensis .

Spruce budworm larvae feed on developing buds and young needles. The yellowish brown caterpillars are difficult to see.

The Spruce needle miner makes a small hole in the base of a needle then mines out the center. Dead needles are webbed together and can be found on infested twigs.

Pine needle scale is a white, elongated scale found feeding on the needles only. Populations would have to be quite high to cause major damage.

Spider mites can be problem in summer after hot dry weather. The small insects can't be readily seen with the naked eye. The first noticeable symptoms are yellowing of the oldest needles on infested branches. Close inspection with a magnifying glass will confirm the presence of the mites.

Sawfly larvae may feed on the needles. One infestation will usually not kill the tree.

Diseases

Several rust diseases attack Spruce but these are rarely seen. Infected needles turn yellow and drop off.

Footnotes

1.

This document is ENH-609, one of a series of the Environmental Horticulture, UF/IFAS Extension. Original publication date November 1993. Revised December 2006. Reviewed February 2014. Visit the EDIS website at http://edis.ifas.ufl.edu.

2.

Edward F. Gilman, professor, Environmental Horticulture Department; Dennis G. Watson, former associate professor, Agricultural Engineering Department, UF/IFAS Extension, Gainesville, FL 32611.


The Institute of Food and Agricultural Sciences (IFAS) is an Equal Opportunity Institution authorized to provide research, educational information and other services only to individuals and institutions that function with non-discrimination with respect to race, creed, color, religion, age, disability, sex, sexual orientation, marital status, national origin, political opinions or affiliations. For more information on obtaining other UF/IFAS Extension publications, contact your county's UF/IFAS Extension office.

U.S. Department of Agriculture, UF/IFAS Extension Service, University of Florida, IFAS, Florida A & M University Cooperative Extension Program, and Boards of County Commissioners Cooperating. Nick T. Place, dean for UF/IFAS Extension.