The pulp is a clean, wood-based, renewable, and biodegradable raw material. It can be used to produce paper, tissue, board, and specialty paper – making them truly sustainable bioproducts. The pulp is also a term used to refer to trees that are grown with the intention of harvesting the timber for use in the production of paper products. Several different types of trees can be used in the creation of this type of wood product, and are usually harvested when they are still relatively young. Along with use in the production of paper products, wood pulp is used in the creation of various types of wood products utilized in the manufacture of inexpensive furniture as well as in clothing and cosmetics.
Important note:
Pulpwood is basically of three different kinds: softwood, hardwood, and residues from mechanical wood processing (sawmillchips and sawdust). "These characterstics would be discussed in a material Section." Materials
The single most common purpose behind pulpwood harvesting is the manufacturing of paper products. Writing paper, as well as computer and copy paper, are made from wood pulp. Household products like paper towels, napkins, disposable plates, and toilet paper are also created using wood pulp Even the glossy paper used in the production of magazines makes use of wood pulp.
“An important aspect as well is that dead trees can also be used for pulpwood”
As the size of the trees in a timber stand increase in height and diameter, they become more valuable since more product classes are available. When a tree grows into a more valuable product class, this is called “ingrowth.”
In a properly managed timber stand, trees with the highest potential will be left to grow into high-value products, such as poles and saw timber — a process that can take 25 to 30 years or more. To help the higher-quality trees reach their full potential and value, lower-quality trees will be selected and removed from the stand, often around the 12 – 15-year mark, depending on your stand’s genetics. This is what’s known as a “thinning.” Once harvested, the lower quality trees are processed into CNS or pulpwood, which return lower but still substantial values.
How to Measure Pulpwood?
Trees of any size can be used for pulpwood, but trees in the range of 5 to 9 inches D.B.H. (diameter at breast height) are normally used. These trees are cut after a saw timber harvest or as a separate operation to thin a crowded stand.
Sometimes, low-quality stands are completely harvested for pulpwood to regenerate the forest to more desirable species.
Also, larger trees with disease or defects that prevent their use for lumber will be used as pulpwood.
Pulpwood is often measured in cords or, more recently, in tons. Cords measure volume, and the amount of wood in a cord varies somewhat, depending on the size of the logs in the stack. A cord of logs 20 inches in diameter will have less air space than a cord of logs 8 inches in diameter. Today, it is common that pulpwood referred to using tons.
For this reason, and because the transport of pulpwood by truck has become common, the forest industry favors weight measures.
Though the weight of a unit of wood can vary by species, size, and season, standard pulpwood weights have been established by law in Mississippi. In 1983, the Mississippi Legislature approved House Bill Number 363 to establish the following official weights for a cord of pulpwood:
- Pine 5,200 pounds 2.6 tons
- Soft hardwood 5,400 pounds 2.7 tons
- Mixed hardwood 5,600 pounds 2.8 tons
- Hard hardwood 5,800 pounds 2.9 tons
These weights do not apply to damaged pulpwood. Pulpwood sold in Mississippi must be sold either by volume (cords) or by weight using these standard weights.
How Does Pulp Turn into Paper?
There are two ways to turn pulp into a paper which are mechanical and chemical pulping:
- Mechanical pulping: Machines are used to grind wood chips into pulp, creating a pulp that retains most of its lignin (a natural glue that binds plant cellulose fibers). Due to the short fibers created by this process, the resulting paper is most suitable for newspapers, phone books, and other low-strength paper uses.
- Chemical pulping: Chemicals separate the lignin from the cellulose, resulting in a pulp that can be used to make stronger paper products.
Mechanical and chemical pulping will be explained on the following page Manufactering process
Sources
Pulpwood. (n.d). MAGNOLIA LAND AND TIMBER, LLC. Retrieved from: http://www.magnolialandandtimber.com/market-your-timber/basic-mississippi-timber-products/pulpwood/
Pulp. (2019). American Forest and Paper Association. Retrieved from: https://www.afandpa.org/our-products/pulp
Timber Products. (2020). TIMBERUPDATE. Retrieved from: https://timberupdate.com/timber-products/