Ponderosa Pine

  
Growth Habits – Ponderosa Pine trees average 100′ to 160′ in height, with some exceeding 180′. The trees range from 2-4′ in diameter, with the rate of growth depending upon altitude, soil, temperature and rainfall.

Mature Ponderosa Pines can be easily identified by their distinctive orange-brown bark which is arranged in large plates. The dark yellow-green needles are 5-10″ long and grow in clusters of three. The cones, similar in color to the bark, are 3-6″ long and 2-4″ in diameter. Seeds are 5/16-3/8″ long with a 3/4-1″ wing.

In pure, or nearly pure, stands of Ponderosa Pine there is a standing inventory of approximately 188 billion board feet of lumber; in mixed stands there are additional billions of board feet in unmeasured inventory. Most Ponderosa trees grow, mature and survive for about 125 years before they are lost to natural causes such as rot, insect damage, fires or wind throw. Occasionally, a lone specimen will survive for nearly 200 years. Their typical site is on semi-arid plateaus and slopes, often surrounded by juniper and sage.

Ponderosa Pine forests are usually selectively harvested rather than clear cut. This method of logging removes only the mature trees and leaves the other trees to re-seed and mature. Selective harvesting often makes it difficult to identify a recently logged stand.

Ponderosa Pine (pinus ponderosa) is one of the Western pine species that includes Idaho White Pine (pinus monticola), Sugar Pine (pinus lambertiana) and Lodgepole Pine (pinus contorta). The Western pines are distinct from the Southern Yellow pines which are denser and pitchier, with widely different characteristics and uses.

Production

The annual production of Ponderosa Pine ranks third in volume after Douglas Fir and Hem-Fir (the two species preferred for structural framing), but second in total value. California and Oregon are the leading suppliers of Ponderosa Pine.

Ponderosa Pine is also sold in export markets, with Mexico the largest foreign customer, followed by Canada, China and Japan. The applications for Ponderosa Pine abroad are very similar to those in the United States.

Manufacturing

Seasoning – All Ponderosa Pine is dried before surfacing to assure uniformity of the finished size. It is seasoned in temperature and humidity-controlled dry kilns or stacked and air-dried until the moisture content reaches the desired level–from 12 to 19 percent.

As with other pines, Ponderosa can be subject to blue stain if a felled tree or green lumber becomes too warm before it is dried. Blue stain does not affect strength and is admissible in some of the lower grades. It can be hidden with paint or enhanced with clear finishes depending on user preference.

Shipping – Ponderosa Pine is usually milled and shipped as a single species and can be specified and bought as such. However, it is sometimes mixed with other species of similar design characteristics, such as ponderosa Pine-Sugar Pine, or Ponderosa Pine-Lodgepole Pine. It is also marketed under the name “White Woods”, which can include a mix of Engelmann Spruce, True Firs, Hemlock and any of the other pines.

Ponderosa Pine Grading & Quality Control

Grading – Lumber Grading Rules assure users of Ponderosa Pine and other softwoods consistent standards of quality, regardless of which mill produces the lumber.

In the 12 western states, the primary growth area for Ponderosa Pine, most pine production is graded under the supervision of Certified Inspectors from the Western Wood Products Association (WWPA), a grading and quality control agency. The most widely produced grades are Selects, Commons and Factory lumber.

Appearance Grades – Ponderosa Pine Boards are graded primarily on appearance for a multitude of applications. There are three grades of Selects and five grades of Commons(WWPA Rules) and there are also Alternate Board grades available (West Coast Lumber Inspection Bureau Rules).

Structural Grades – Ponderosa Pine structural grades are used where light to moderate strength levels are required. The 2×4 and 2×6 sizes are especially popular as decking material, once the lumber has been pressure treated with preservatives for outdoor uses.

Factory Grades – Factory and Shop grade lumber products are intended specifically for manufacturing. The grades have evolved on the basis of millwork cutting sizes and are defined by the number of clear standard size cuttings which can be obtained by ripping and cross cutting the various grades.

Characteristics & Best Uses

Ponderosa Pine has a minimal amount of reddish-brown heartwood and an exceptionally wide sapwood which is honey-toned or straw-like in color. It has a straight, uniform grain which machines to a clear, smooth surface. When freshly sawn or surfaced, its pleasant smell is reminiscent of the forests where it grows. Ponderosa Pine is often specified when appearance rather than strength is of primary importance.

Dimensional Stability – All woods shrink and swell to some degree as their moisture content fluctuates with atmospheric conditions. However, Ponderosa is relatively unaffected by changes in humidity after drying, making it valuable for work that requires close-fitting joints. It has a uniform cell structure and shrinks only a moderate amount, in comparison to other softwood species. It seasons beautifully with minimal splitting, cupping, or warping.

Residential Construction – Appropriate applications for Ponderosa Pine include light framing, spaced sheathing, floor and roof decking. As a treated product, it is superb for decks and other outdoor projects. Although it is not as strong as some of the heavier, denser softwoods, Ponderosa’s combination of dimensional stability, strength and workability is well adapted to most light framing applications including joists, studs, rafters, plates and soffits. The wood resists splitting when nailed which allows for the use of larger nails and increases nail rentention.

Traditional outlets, such as retail lumber yards and most home improvement centers, usually carry and extensive inventory of Ponderosa Pine products. Both amateur and professional remodelers also find many applications for Ponderosa in home repairs, paneling, decks, renovation, retrofitting and room additions.

Factory and Shop Products – Ponderosa Pine is well suited for remanufacturing which requires clear, splinter-free wood, with a minimum of knots, resin and other unwanted characteristics. The large trees include substantial volumes of virtually clear sapwood with relatively few, widely-spaced knots. Shop and Factory lumber is graded to yield standard cuttings of clear material suitable for fabrication. Such wood is selected to be almost completely free from pitch and resin pockets, has an even grain and is dimensionally stable. Ponderosa also ranks moderately high for ease of gluing and is used for all types of products where glued-up construction is required.

The species is prized for moulding and for doors, windows, frames and drawers where durability under movement is essential. It has the ability to withstand scuffs, shocks and jars without spliting, which makes it the premier wood for these and other applications such as sashes, jambs, shutters, screens, columns, stairwork and fascia. 

Paneling – Pine paneling is often associated with Early American decor in kitchens, family rooms, dens and bedrooms. However, new finishing techniques and patterns make it appropriate for contemporary or traditional settings.

Many patterns are reversible, offering a choice of pattern or surface finish in a single panel. However, it’s important to remember that paneling boards are inspected and graded on the patterned or face side; the back or reverse side may have characteristics which would make it a lower grade, but desirable for a specific design effect.

Most lumber dealers carry a limited selection of paneling patterns in stock, but can special order any of the standard patterns. Some dealers will arrange to have a unique pattern custom milled.

Woodworking and Furniture – Many of the properties that make Ponderosa Pine a first choice for paneling also put it at the top of the list for furniture and architectural woodwork such as built-in bookcases, benches, cupboards, desks and kitchen cabinets.

Cabinetmakers and woodworkers appreciate the wood’s uniform cell structure, scarcity of resin pockets, and resistance to splitting. Finished parts fit together snugly without binding. The lumber is easy to work with either hand or machine tools and converts readily into fine mouldings and cabinet work.

In the last few years there has been a resurgence in the popularity of pine furniture–antique pieces, new pieces from old pine and new pieces from new lumber. Honey-toned Ponderosa Pine is a natural accompaniment to the country look, while simply-styled bleached pine is appearing with increasing frequency in contemporary furnishings. Ponderosa Pine furniture is available both finished and unfinished, in a variety of styles and qualities.

Finishing – Ponderosa Pine takes most finishes beautifully, including paint, stain, lacquer and varnish. Unlike some of the heavier woods, paints and stains do not raise the grain; however, knots should be sealed before painting to prevent them from bleeding through the finished surface.

Treated Products for Outdoor Projects – The use of treated Ponderosa Pine continues to increase particularly in the western and upper mid-western parts of the country. It can be used for fences, planters, storage sheds, play structures, decking, deck railings, benches and other outdoor projects.

The large proportion of sapwood in Ponderosa makes it well suited to pressure treating because the preservatives can penetrate the sapwood cells deeply and uniformly. Only seasoned (dried) lumber is used in the treating process and after treatment, the wood should be allowed to reach equilibrium moisture content with the surrounding atmosphere before it is installed in its permanent location. The quality-control mark, shown right, should appear on treated lumber.

Ponderosa Pine can be treated for above-ground or in-ground contact, and unlike some softwoods, it can be pressure treated for in-ground use without incising (perforating) the wood. The waterborne preservatives leave a clean, dry, odorless surface ready to be painted or stained. The treated product holds up well in storage, making it easy to yard for distributors and retailers, which in turn, makes it readily and widely available.

In addition to the standard dimensions, treated Ponderosa Pine is also available in two WWPA radius-edged decking grades, Patio I and II, which are milled expressly for use as outdoor decking.

The American Wood Preservers Association (AWPA) provides treating standards and retention levels for a number of preservative and fire-retardant chemicals. All pressure-treated wood should bear the mark of a quality control agency approved by the American Lumber Standard Committee. Chemical retention is stated in terms of the weight of the chemical retained (in pounds) per cubic foot (pcf) of wood after treatment; the larger the number, the more chemical retained.

For more information refer to the Western Wood Preservers Institute’s brochure Guide to the Characteristics, Uses and Specifications of Pressure Treated Wood.

Industrial Uses – Industrial uses for Ponderosa Pine include pallets, concrete forms, crates and boxes, dunnage, hives, partitions and foundry patterns. It is also used for a wide variety of wood packaging and novelty items such as boats, wagons, toys, window shade slats, rat and mouse traps.

Additional Information

For additional information on grades, design values and spans, refer to WWPA’s Product Use Manual. For additional four-color pictures of Western lumber in a variety of species and grades, refer to the following Western Wood Species books:

Volume 1: Dimension Lumber
Volume 2: Selects-Finish/Commons-Boards
Volume 3: Factory Lumber

For additional information on WWPA pattern options, in profile, refer to WWPA’s Standard Patterns.

For additional information on treated lumber, contact the Western Wood Preservers Institute.

Quality control

The WWPA grademark identifies Western Lumber products backed with assurances for quality, performance and technical support. WWPA maintains a team of lumber inspectors throughout the Western region to monitor the grading and quality control of Western Lumber products from WWPA Member mills, ensuring products consistently meet grade specifications. Additionally, WWPA has technical experts on staff with training and work experience in design, engineering, lumber specifications, code conformance, construction, manufacturing, wood technology and forestry. From the Association’s headquarters, these experts offer technical assistance in all aspects of Western Lumber end use for WWPA Member company products.