Red Spruce (Rubens)

The Red Spruce (Rubens) is generally described as a perennial tree. This is native to the U.S. (United States) has its most active growth period in the spring and summer . The greatest bloom is usually observed in the mid spring, with fruit and seed production starting in the summer and continuing until fall. Leaves are retained year to year. The Red Spruce (Rubens) has a long life span relative to most other plant species and a moderate growth rate. At maturity, the typical Red Spruce (Rubens) will reach up to 110 feet high, with a maximum height at 20 years of 25 feet.

The Red Spruce (Rubens) is easily found in nurseries, garden stores and other plant dealers and distributors. It can be propagated by bare root, container, cuttings, seed. It has a slow ability to spread through seed production and the seedlings have medium vigor. Note that cold stratification is not required for seed germination and the plant cannot survive exposure to temperatures below -47°F. has medium tolerance to drought and restricted water conditions.

Uses of : Landscaping, Medicinal, Culinary, etc.

Red spruce is one of the most important forest trees in the northeast. The wood is light, soft, narrow-ringed and faintly tinged with red. It is the most common species of eastern spruce lumber. Because of its resonance, it is especially adapted to sounding boards in musical instruments. It makes up a large percentage of spruce pulpwood produced in the northeast. It is used as a Christmas tree also.

Red spruce provides food and cover for various mammals and birds. The spruce grouse feeds on the buds and foliage; red squirrels eat buds and seeds; varying hare browse twigs and foliage; porcupines feed upon the bark. Red spruce seeds make up 25 to 50 percent of the diet of white-winged crossbills. Red spruce can be an important cover tree in northern New England deer yards.

General Characteristics

Red spruce reaches heights of 60 to 80 feet with trunk diameters of nearly two feet. Larger sizes are attained in the southern Appalachians. Needles are four sided, dark, shiny, yellow-green, and about 1/2 inch long, growing singly from all sides of the twigs and branches. The slender new twigs have a reddish coat of down through the first year. This, together with the short incurved needles, help distinguish red spruce from most other spruces. There are about 139,000 seeds per pound.

Required Growing Conditions

In northern New England it is found mainly on shallow till soils that average about 18 inches deep to a compact layer. At higher elevations it often grows in organic soils overlying rocks. On poorly drained soils, lack of aeration limits its growth. In the northern part of its range, red spruce grows at elevations from near sea level to about 4,500 feet. In the southern Appalachians it is limited to slopes and mountain tops above 3,500 feet in West Virginia and above 4,500 feet in Tennessee and North Carolina.

Unfortunately, red spruce is showing damage from air pollution throughout its range, particularly at the higher elevations.

Cultivation and Care

Good seed production of red spruce usually begins after the tree is 30 years old. Heavy seed crops occur every three to eight years. Spruce seedlings have exceptionally slow growing, fibrous, shallow roots. Consequently, a critical survival factor in natural establishment is the depth of the organic layers on which the seed germinates. If the thickness of the layer exceeds two inches, the roots of spruce seedlings may not reach mineral soil and the moisture needed to carry them through dry periods. Red spruce is very shade tolerant, but requires nearly full sun light for optimum development.Red spruce can be established in nurseries as easily as any of the other spruces. It is used some for reforestation in the northeast.

General Upkeep and Control

Red spruce has not generally received intensive management in the northeast. It can be harvested by partial cutting or clear cutting depending upon local markets and silvicultural conditions. Weeding and releasing, if needed, should be done at an early age, 10 to 15 years.

Pests and Potential Problems Red spruce has several insect enemies, the most important being spruce budworm. Budworm damage may be heavy in stands that contain a large percentage of balsam fir. Some stands of red spruce may be susceptible to damage by the eastern spruce beetle, European spruce sawfly and yellow-headed spruce sawfly. Disease problems are minor in management of red spruce.

The overall health of red spruce stands seems to be declining due to pollution factors. Weakened trees are more susceptible to insects and disease.

Plant Basics
Category
Growth Rate Moderate
General Type Tree
Growth Period Spring, Summer
Growth Duration Perennial
Lifespan Long
Plant Nativity Native to U.S.
Commercial Availability Routinely Available
Physical Characteristics
Bloom Period Mid Spring
Displays Fall Colors No
Shape/Growth Form Single Stem
Drought Tolerance Medium
Shade Tolerance Tolerant
Height When Mature 110
Vegetative Spread None
Flower Color Yellow
Flower Conspicuousness No
Fruit/Seed Abundance Medium
Fruit/Seed Seasonality Summer Fall
Seed Spread Rate Slow
Gardening Characteristics
Propagations (Ways to Grow) Bare Root, Container, Cuttings, Seed
Moisture Requirements Medium
Cold Stratification Required No
Minimum Temperature -47
Soil Depth for Roots 13
Toxic to Nearby Plants No
Toxic to Livestock No
After-Harvest Resprout Ability No
Responds to Coppicing No
Growth Requirements
pH Range 4–5.8 pH
Precipitation Range 28–28 inches/yr
Planting Density 300–700 indiv./acre
Soil Textures Coarse, Fine, Medium
Soil Depth for Roots 13
Minimum Frost-Free Days 90 day(s)
Salinity Tolerance None
CaCO3 Tolerance Low
Sustainability & Use
Leaf Retention Yes
Palatability Low
Fire Resistant No
Causes Livestock Bloating None

Source: USDA, NRCS, PLANTS Database, plants.usda.gov.
National Plant Data Center, Baton Rouge, LA 70874-4490 USA