Arborvitae (Occidentalis)

The Arborvitae (Occidentalis) 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 Arborvitae (Occidentalis) has a long life span relative to most other plant species and a slow growth rate. At maturity, the typical Arborvitae (Occidentalis) will reach up to 50 feet high, with a maximum height at 20 years of 25 feet.

The Arborvitae (Occidentalis) 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 moderate 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 -33°F. has low tolerance to drought and restricted water conditions.

Uses of : Landscaping, Medicinal, Culinary, etc.

Conservation: More than 120 named cultivars of northern white cedar have been named and used as ornamental trees and shrubs, where the name “arborvitae” is usually applied. Selections offer variety in habital form, color, cold hardiness, heat tolerance. It is often used for hedges and other types of border or shelter plantings. The species was introduced into Europe for cultivation in the 16th century.

Wildlife: Stands of northern white cedar also are valuable for wildlife habitat, particularly in severe winters for white-tailed deer, which use it for both shelter and browse. These trees also provide habitats for many species of birds.

Industry: The wood’s light weight and resistance to decay makes it useful for a number of applications. The principal commercial uses of northern white-cedar are for rustic fencing and posts; other important products include cabin logs, lumber, poles, and shingles. Smaller amounts are used for paneling, piling, lagging, pails, potato barrels, tubs, ties, boats (especially canoes), tanks, novelties, and woodenware. The timbers were used to make the ribs in birchbark canoes. Cedar leaf oil is distilled from boughs and used in medicines and perfumes. Boughs are also used in floral arrangements.

Ethnobotanic: The essential oil of northern white cedar is used in cleansers, disinfectants, hair preparations, insecticides, liniment, room sprays, and soft soaps. The Ojibwa are said to have made soup from the inner bark of the young twigs. The twigs are used by some to make teas for relief of constipation and headache.

General Characteristics

General: Cypress family (Cupressaceae). Native shrub or tree growing to 15 (-38) meters tall, the crown narrowly conic to broadly pyramidal, with spreading, densely crowded branches; branchlets flattened, in fan-shaped sprays. Bark is gray to reddish-brown, 6-9 mm thick, fibrous, separated into flat, connected ridges. Leaves are evergreen, scale-like and abruptly pointed, 2 mm long, opposite in alternating pairs (in 4 rows), bright green above and pale green below, sometimes becoming yellow-brown in winter, with a spicy fragrance when crushed. Seed cones are ellipsoid, (6-)9-14 mm long, brown; seeds ca. 8 per cone, 4-7 mm long, with lateral wings about as wide as the body. The common name pertains to its northern

Required Growing Conditions

The primary range of northern white-cedar is in eastern-southeastern Canada (west to Manitoba) and adjacent states of New England and the Great Lakes region (west to Minnesota); south of the main range, it occurs in scattered stands and southward along the Appalachians into North Carolina and Tennessee, where it is generally rare or extirpated. For current distribution, please consult the Plant Profile page for this species on the PLANTS Web site.

Adaptation It commonly grows in cool, moist, nutrient-rich sites, on mostly calcareous soils that are neutral or nearly so -- lakes and river shores, uplands, cliffs, and talus, at 0-600 (-900) meters elevation. Although it grows best on well-drained sites, it may be dominant in swamps. In cultivation, it grows in a wide variety of soils.

Cultivation and Care

Cones may be produced by northern white-cedars as young as 6 years old, but seed production in large quantities begins when the trees are about 30 years old and is best after 75 years. Good seed crops are produced at intervals of 2 to 5 years, or more frequently in local areas.

Seedbeds of moss-covered, decaying logs and stumps account for more than 70 percent of the northern white-cedar seedlings in undisturbed areas. Seedlings can be established on burns, if the burn was severe enough to expose favorable, mineral soil seedbeds on uplands or to improve moss seedbeds in swamps. Best root and shoot development occur in full light, but drought-caused mortality of northern white cedar seedlings may be extremely high under any light condition.

Layering may account for a significant portion of northern white-cedar reproduction in swamps, because adventitious roots can be produced from any branch or stem. It is most common in young stands and those with leaning trees, where the lower branches become covered by moss. New trees also develop vegetatively from uprooted trees where roots are formed from vertical branches.

Northern white cedar grows relatively slowly in swamps or on other saturated lowland sites, but it apparently reaches ages of 400 years and greater in these habitats. An individual from Ontario has been dated at more than 1650 years old.

General Upkeep and Control

Northern white-cedar forests are stable without major disturbance such as fire because the trees are long-lived and balsam fir is the only important associate sufficiently shade tolerant to grow in competition. In stands that have been opened by timber harvesting or severely browsed by white-tailed deer, succession is often to balsam fir or swamp hardwoods, especially black ash. Northern white-cedar responds well to thinning-release after successful establishment, although it is shade tolerant and can withstand severe suppression for several years.

Even-aged management, through shelterwood cutting or clear cutting is recommended for maximum benefit to deer. Satisfactory reestablishment after clearcutting often requires some kind of site preparation, particularly broadcast burning of slash. In some areas, however, heavy winter browsing of seedlings and saplings by deer greatly reduces reproductive success.

Plant Basics
Category
Growth Rate Slow
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 Low
Shade Tolerance Intermediate
Height When Mature 50
Vegetative Spread None
Flower Conspicuousness No
Fruit/Seed Abundance Medium
Fruit/Seed Seasonality Summer Fall
Seed Spread Rate Moderate
Gardening Characteristics
Propagations (Ways to Grow) Bare Root, Container, Cuttings, Seed
Moisture Requirements Medium
Cold Stratification Required Yes
Minimum Temperature -33
Soil Depth for Roots 30
Toxic to Nearby Plants No
Toxic to Livestock No
After-Harvest Resprout Ability No
Responds to Coppicing No
Growth Requirements
pH Range 5.2–7 pH
Precipitation Range 35–35 inches/yr
Planting Density 300–1200 indiv./acre
Soil Textures Coarse, Fine, Medium
Soil Depth for Roots 30
Minimum Frost-Free Days 100 day(s)
Salinity Tolerance None
CaCO3 Tolerance High
Sustainability & Use
Leaf Retention Yes
Palatability Medium
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