Paulownia Trees - Biomass, Timber and Land Reclamation
Paulownia trees are the new tree plantation tree, particuarily the fast growing paulownia clones that are used for timber, land reclamation, biomass, poles and pulp. Paulownia trees harvested at 100 board feet each typically bring in about $45,000 wholesale and $90,000 retail per acre.
Paulownia is an extremely fast-growing soft hardwood native to China. It is the number one plantation tree throughout Asia and Australia. The heartwood is light in color and its appearance closely resembles that of American Ash. The demarcation between heartwood and sapwood is not as clear as most hardwoods and the wood is straight grained and lustrous. Paulownia is surprisingly light in weight for a hardwood. In fact the physical weight is slightly less than kiln dried western red cedar. It is low in overall strength, but has high strength to weight ratio – physically it ranks between balsa and poplar. The wood dries rapidly and does not easily warp, cup, end check, splinter or split and has a very small shrinkage coefficient. It is used as firewood but has a low BTU rating.
As the supply of natural habitat trees dwindle, a new market is developing for plantation grown Paulownia. An estimated 6 million acres is under Paulownia cultivation outside Asia and timber marketers estimate it will be decades before growers will be able to adequately meet the growing demand for Paulownia wood. Specifically bred clones of Paulownia can reach 10 to 16 feet in height in the first season eventually growing to approximately 60 feet in less than 10 years. Timber clones of Paulownia varieties are developed specifically for wood growth. Paulownia timber trees are produced from the best trees by a process of tissue culture cloning or root reproduction. An exact genetic replica of the best performing trees that have proven to be superior in growth rate, size and hardiness are chosen as specimen trees.
Paulownia is widely used in Asia for furniture, decorative paneling and musical instruments. It is light and strong with a silky smooth finish and takes a wide range of stains. Plantation grown timber produces straight grained, knot free timber. Paulownia timber could substitute for broad leaf timber that is harvested from the tropical rain forests of Asia, South America and Africa.
At 3 to 4 years of age Paulownia trees can produce a very straight cylindrical pole with no side branches or deformities 18 feet in height and 10-12" thick. This log is light but very rigid and it will not sag under heavy loads, making it ideal for construction. In Shandon, China, 4 year old poles are now used as ridge poles and uprights and 3 year old poles are used as rafters to support concrete and clay tiled roofs. Villagers claim that the poles are stronger and less prone to sagging than the traditional conifer poles.
Paulownia can be sliced or peeled finer than any other timber and still maintain its structural integrity. In Taiwan, Paulownia is sliced to 1/1000 inch and veneered onto paper for decorative purposes. Paulownia veneer can be used to face composite timber products and make them more attractive. Most high quality veneer timbers are becoming increasingly expensive and harder to find as they normally come from broadleaf trees harvested from old growth forests. Veneer is the highest value end use for Paulownia timber.
Paulownia is ideal to use for moldings, architraves and wall paneling as the wood is light, strong and finishes well.
Paulownia has excellent prospects for pulp as it can be harvested on a three to four year rotation after which it can be coppiced and allowed to regrow. The timber's long strong fibers are light colored and require little bleaching. The Paulownia pulp yield per cubic meter of timber is comparatively low so it is best mixed with other timber pulps such as Hybrid poplar.
Paulownia Wood Product Advantages
Once a Paulownia Tree is harvested, a new tree will grow from the old stump making it one of the best regeneration for timber trees. The same root can generate a new tree every 8 to 12 years. Paulownia is moisture resistant, strong and lighter than any other US grown commercial timber. It offers an environmentally sound alternative to expensive tropical woods like Balsa, Teak and Miranti. It’s also a great alternative for old growth woods like Western Red Cedar and Redwood. Paulownia can save forests by producing sawn timber in 7-12 years and growing 2-4 times more lumber than most other commercial trees in the same time period. This is vital as supplies of exotic hardwoods rapidly diminish. Paulownia is proving to be one of those rare environmental solutions that also makes economic sense.
Comment from contributor A:
As I work with it, I like the wood more and more. I have found it to be rot resistant and termites do not like it. It dries easy and fast with little defect other than a light sticker stain if not laid with dry stickers. Paulownia wood makes good paneling, and some here are starting to carve it. Paulownia wood has a nice finish and machines and glues well. I found that I needed to remove the stump from the tree I harvested so it wouldn't grow back. The roots were breaking up my driveway.
Comment from contributor B:
Ha! Paulownia is the wonder tree that is going to save our rainforests. You can harvest it in just 10 years; it's as light as balsa and as strong as hardwoods, has great grain and is a very sustainable product that can be used for anything. I know some HWS (hollow wood surfboard) builders that would pay good money for that wood in your area. There are lots of guys on the east coast who are buying it but they can only get container loads from Australia. And none of them can afford that for their hobbies. I think the going rate is about $10-11/bft.
Comment from contributor C:
There is a definite correlation between tree size and economic value. Although trees are limb pruned early reduce blister rust of juvenile trees, an equally important reason is to start creating clear boles. Eventually, trees are pruned free of limbs to an eighteen foot height. Since crop trees are headed for a long life and large diameter, this early limb pruning pays great economic dividends. Left to natural pruning phenomenon, the trees would have to reach 100 plus years before their trunks would be growing clear faces. And since there is a manifold differential between the value of clear wood and knot-studded wood in Paulownia lumber (or in any lumber or veneer for that matter) early pruning is dramatically valuable.
Comment from contributor D:
The quick growth of Paulownia is a double-edged sword. For the plantation manager, a profit can be realized much more quickly on a smaller plot of land. But the return of land to any semblance of a natural state anywhere near your plantation is not at all likely, because of the prodigious amount of seed that Paulownia's produce, which is then spread far and wide by the wind, water, and animals. In other words, many worry that Paulownia is really an invasive species that will spread to other areas and over grow natural habitats.
Paulownia is considered by many as the “go to” tree for biomass wood lots. It’s fast growing; builds caliper quickly is low maintenance and regrows.
The site should be relatively flat and well draining. Paulownia does not do well in flood plains or low valleys where water can pool. A sandy loam is the best soil type. Planting a bean crop such as soy a year before planting will add nitrogen to the soil. The land should be tilled under and disked in parallel rows. Planting Paulownia seedlings 10 to 12 feet apart is suggested. Planting agro forestry crops such as cucumbers and/or pumpkins will inhibit weed growth, which if left to grow would compete with the trees.
Care & Maintenance
Explosive growth rates can be attained with heavy watering and periodic applications of fertilizer. Terminal growth of 10 feet per year is not uncommon in ideal conditions.
Paulownia clones cost about $800 per 50 pounds, which is enough to plant one acre. Water costs, fertilization, agro cropping and labor may run another $2,000 to $4,000 per acre depending on crop type and available water.
Invest In A Paulownia Tree Plantation
Paulownia sells wholesale for around $1.50 per board foot and as much as $3.00 retail per board foot. An acre growing 300 trees would bring in gross profit of $45,000 wholesale and $90,000 retail providing each tree harvested out at 100 board feet each.