From the structures we call home, to the colored mulch in our flower bed, to the wooden pallets that deliver the goods we rely on, products from grown forests play a crucial role in our lives.
So exactly what are forest products? Simply stated, forest products are materials derived from trees that are used for commercial use or consumer consumption. When most of us think about forest products, we typically focus on wood products such as lumber, structural panels, and paper.
Forest products include a range of non-timber items such as fruit, nuts, seeds, sap, and oil. In this installment of the Nature’s Packaging blog, however, we turn our attention to forest products that are derived from wood, and the wood-based forest products industry.
The Forest Products Industry
The forest products industry is an important contributor to both the Canadian and U.S. economies. It accounts for around 1.5% of the U.S. economy and contributes about 5% of the nation’s total manufacturing output. Regionally, it can be very significant. Forest products ranks as one of the top three contributors in some southern states. Canada’s forest sector contributed $23.9 billion to Canada’s GDP in 2019 or about 1.4%.
The forest industry comprises three main subsectors:
- solid wood products manufacturing
- pulp and paper
- forestry and logging
Solid wood products manufacturing includes primary activities such as lumber and structural panels, as well as secondary products such as millwork, engineered wood products and wood packaging.
The pulp and paper product manufacturing subsector produces a wealth of products, covering everything from newsprint and household tissues to dissolving pulp for rayon production.
The forestry and logging subsector spans field operations and timber harvesting, including logging and transportation to mills.
Tree Harvest for Various Products
The harvest of trees generates three types of material, including sawtimber (including chip-n-saw), pulpwood, and finally harvest slash. Sawtimber, used to make products such as lumber and veneer, is typically most desirable. This is followed by pulpwood. Slash refers to the treetops, limbs, and other woody material left behind after logging takes place. The amount of slash generated is influenced by variables such as the size and quality of the harvested trees.
In the US South, for example, pine trees usually mature between 25 and 40 years, with thinning operations undertaken at 12-15 years and then again at 18-22 years, allowing trees the space they need to grow to maturity. As trees become larger, they become more valuable on a per-ton basis. Forest owners, therefore, are motivated to maximize their yield of mature timber.
Logs of a larger diameter are usually categorized as sawlogs, while those of a smaller diameter are considered pulpwood. Smaller diameter trees may be classified as unmerchantable. According to Forest2Market, plantation pine logs can be designated as follows:
- 5”-7” diameter at breast height (DBH) – pulpwood
- 8”-11” DBH – chip-n-saw
- 12”+ DBH – sawtimber
Wood-based Forest Products
Natural Resources Canada suggests that forest products can be categorized into four segments: solid wood products (including lumber and structural panels), wood pulp, paper products (including newsprint, printing, and writing paper), and bioproducts (e.g. biofuels, biochemical, bioplastics) derived from biomass.
Lumber refers to harvested timber that is milled into products such as dimension lumber, and boards. Softwood dimension lumber is used mostly for framing purposes in residential construction. Lower-grade material is typically used for wood packaging products such as pallets. Logs may also be peeled from the outside in to create veneer. Veneer can be glued into layers or plies to make plywood. Other structural board products include oriented strandboard (OSB) and fiberboard. Cross laminated timber, constructed from glued layers of solid wood, is becoming increasingly popular.
Wood pulp is the term for wood fiber that has been reduced chemically or mechanically to pulp for use in the manufacture of paper and other products. Pulp can be derived from virgin forest harvest material such as pulpwood as well as from wood processing residuals. Pulp is used as an intermediate product to produce paper, packaging, hygiene, and textile products.
Biomass is generated from a variety of sources, including the branches and tops of trees after harvest, forest thinning and salvage, wood products manufacturing residuals and wood products recycling. Biomass has been a substantial energy source for the pulp and paper industry. Biomass is also used for a variety of other uses, including pulp feedstock, pellets, structural board, animal bedding, soil amendments, landscaping mulches and more.
There are also exciting new opportunities for bioproducts such as biochemicals and biomaterials. According to Natural Resources Canada, the growth potential and projected market size for emerging bioproducts are much greater than for traditional forest products combined, including pulp, lumber and newsprint.
Forest products sourced from sustainable North American forests are critical to our daily lives. In the future, there is also the exciting potential for new and emerging forest products to take center stage, further accentuating the importance of timber in our everyday lives.