How long do you stake a tree


Tree Staking FAQs: Why, When & How to Stake a Newly-Planted Tree

You’ve probably seen many newly-planted trees held up with stakes. And you may have wondered whether staking a tree is really necessary, what the best way is to stake a tree, and how long a tree should be supported with stakes.

In this article, we answer all of your questions about staking a tree.

Why are trees staked?

Often, it depends on who you ask. Nurseries may stake young trees to ensure they grow vertically and are easy to move, gardeners and contractors may stake new trees to protect them while they establish roots, and some people stake their trees because that’s what everyone else does.

Realistically, staking young trees is more complicated than these reasons. You need to understand your tree species, its root ball and crown, your planting location, and the on-going care that your newly-planted tree will receive.

Nurseries often stake (and protect) young trees – but that doesn’t mean you should do the same when you plant it at home.

Does staking help a tree?

It depends! For young, nursery-grown trees in pots, being tied to a central nursery stake means space savings; young trees can be grown close together and gain vertical growth fast. When these young trees are transplanted and have their central stake removed, their tall, slender form may need tree-stake support while their trunk, branches, and root ball grow.

For field-grown nursery trees that are balled and burlapped, their excavation from the field may mean that their crown is larger than their excavated rootball can support. In this case, stakes serve to hold the tree in place after transplanting while the tree’s rootball is growing in and the tree is stabilizing itself.

Does staking harm a tree?

It can. Tree stakes are not intended to be a permanent addition to transplanted trees. Ideally, their usefulness is regularly evaluated by an arborist, public works crewmember, or experienced gardener and stakes are removed as soon as their purpose has been achieved.

Reality is often different, though, with trees going un-examined and stakes remaining in place long after their usefulness is over. This is when stakes can start damaging a growing tree.

One way that long-term staking damages a tree is that it prevents its natural movement in the wind. When wind blows around the crown and trunk of a young tree, the tree responds by producing natural growth hormones. These growth hormones encourage an increase in the girth, or diameter, of the trunk and branches. Movement also encourages a tree trunk to taper, making it thicker at the base and thinner toward the top of the trunk.

This young conifer tree is growing well without any kind of staking.

Should all newly-planted trees be staked?

As usual, it depends! A rule of thumb is that if the central leader, or main trunk, of a tree can’t stand up on its own after it is transplanted and its nursery stake removed, it will need staking. This will keep its trunk vertical as the rootball and lateral branches develop.

Most arborists and tree-care professionals prefer minimal staking, as a tree’s natural development in response to its environment is its best protection. But professionals also understand that a large transplanted tree, either field or container-grown, may not have enough of a root system to support its dense or spreading crown, particularly if its planted in an exposed or windy site. This is when staking is most useful.

If you’re having a tree professionally installed, be sure to ask about follow-up monitoring so stake removal can be done as soon as possible.

Are there any kinds of trees that should not be staked?

Tree-staking decisions have less to do with a tree’s species and more to do with their size, form, and the conditions where they are being transplanted.

A whip, or very young tree, is generally so small that it won’t need staking. And whips establish in place, so their roots and crown develop in direct response to their growing conditions, ensuring future stability.

Likewise, a narrow, upright tree may be less likely to need staking in comparison with a spreading, dense-crowned tree. This is because windy conditions often determine staking needs; a large, wind-catching tree crown with a small rootball is more likely to be pushed over.

Trees that don’t need staking also include trees that are staked for protection from mowers or string trimmers. Better methods for protecting these trees are to always keep a ring of mulch around the base of the tree, or to erect a fence to encircle and protect the tree.

What should you use for stakes?

Stakes can be wood or metal, as long as it’s strong enough to be driven into the soil.

The stakes’ height should correspond to the location on the tree’s trunk where ties will be attached. A rule of thumb is that stakes should be 1/3 the height of the tree, but the exact height is less important than a well-installed staking system.

Sometimes trees are staked or anchored just because people assume it’s what they’re supposed to do. Unfortunately, it’s often done incorrectly (such as only using 2 anchors for this guyed tree) or unnecessarily.

Sometimes anchors are used instead of stakes, and you’ll see lines of flexible material from the ground up to the tree’s trunk and lowest sets of branches. This is called “guying”, and usually involves three ground-level anchors evenly distributed around a tree’s planting hole, with flexible material from each anchor encircling one place along the trunk or branches of the tree.

Where should stakes be placed?

Always position your stakes outside of the transplanted tree’s rootball, and always position your stakes according to the prevailing wind direction. If you’re using a guying system, wind direction is not a deciding factor; even distribution around the trunk is.

If you’re having your tree professionally installed, always make sure your installer knows tree-staking best practices.

How do you tie a tree to the stakes?

By Dvortygirl – Own work, CC BY-SA 3. 0

Soft, flexible ties should be attached to the stakes and tied to loosely encircle the trunk. Don’t tie them too tightly or it will slowly “strangle” (girdle) the tree as it grows. You want to encourage movement of the tree while providing gentle support, not immobilize it.

Tying a tree so that it cannot move is also a problem. The top of the tree will move freely in the wind but all movement will suddenly stop where the tree is tied. As a result, it can cause the trunk to snap off just above the attachment point.

Attach your ties at the lowest practical height. The goal is to find the lowest point on a tree’s trunk (like a center of gravity) that will allow natural movement in the wind without trunk breakage. This should also prevent branches from damaging or being damaged by any nearby structures as they blow around, or impeding pedestrians (branches over public sidewalks should clear 7’-8’ in height).

Is there anything I should not use to tie a tree?

Yes. Never use rigid, hard, or abrasive ties, or any ties that wholly immobilize the tree. Hard, abrasive ties will cut into a tree’s bark, risking trunk girdling; taut ties prevent the natural, flexible movement of the trunk and will stunt its growth.

Wire ties are a major cause of damage to newly-planted trees, as are zip ties, plastic rope, or an otherwise flexible material pulled too tight.

How long should the tree be staked?

A general rule is from six months to two years maximum, but trees should be examined regularly and stakes removed as soon as a tree is stable. This can be less than two years, or more, depending on conditions, or it can be longer if the tree establishes slowly and the conditions are harsh.

How do I know if it’s been staked long enough? Or staked for too long?

Leaving a tree staked for too long can lead to tree damage By WayneRay – Own work, CC BY-SA 4.0

If you remove the flexible ties from your tree’s trunk and it stays upright, especially in wind, chances are it has established itself enough to remove both ties and stakes. All trees are flexible, and the soonest a tree’s trunk can increase its girth in response to wind, the better.

Stakes that are left on too long often look too small in relation to a tree’s size, or a tree’s trunk has expanded in diameter so that it pulls the flexible ties taut. If you have a tree whose trunk is larger than its wooden stakes, chances are it’s outgrown them.

What happens if I remove the stakes too soon?

Removing stakes too soon can result in a newly-planted tree leaning or blowing over in the wind. A tree doesn’t have to completely blow over to become damaged; roots that are ripped or severed from excessive wind can stunt or kill a tree from stress and because water and nutrient uptake is stopped.

All plants are photoresponsive, meaning they grow toward the strongest light (the sun), which keeps them vertical. A flexible tree will try to establish a balanced crown and stable trunk while growing, but excessive stress from wind will shape it in response to the wind’s direction. This can be striking in coastal pines and cypress that have windblown forms but, for safety and longevity, a strong central leader and an even crown are best.

The only stake you can never remove too soon is the nursery stake that may accompany a tree that’s grown in a nursery pot. As soon as your tree is transplanted (with or without a new two-stake-with-ties system), cut all ties that attach the tree to its central nursery stake and gently pull the stake out vertically, making sure you don’t scrape the bark. Chances are you’ll be able to see small indentations in the bark where the trunk was lashed to the nursery stake while its trunk expanded.

What if I remove the tree stakes too late?

Stakes left on too long can harm trees in several ways. First, if the stakes remain rigid and hold the tree too tightly, the tree’s trunk will not develop its natural girth and strength. The early development of a tree lays the foundation for its future growth, so there should be as few impediments as possible.

Stakes themselves may crack or become unstable and lean. With the tree attached to the stakes by flexible ties, if a stake leans or falls over it takes the tree with it. The tree doesn’t have to fall over to become damaged; roots left in tension from the constant pull of the stakes and the leaning tree will be damaged or die.

A tree that outgrows the location of its stakes can be damaged by them. The tree’s naturally flexible trunk and branches often bend in the wind. If they hit a rigid stake, the repeated striking and abrasion can result in girdling.

Other things to look out for are flexible ties that have wire or cable in their center. If the flexible covering wears away, the sharp, rigid metal is exposed and will cut and girdle the tree’s trunk.

Are there any things I should look out for with a staked tree?

The best way to ensure your tree’s health is to regularly check it. After the first winter, check the looseness of the ties and check the trunk for any signs of damage. These could be indentations in the trunk, or worn areas of bark.

A test of your tree’s stability in windy conditions is a good way to evaluate its need for staking. Temporarily remove the flexible ties and observe the tree’s movement in the wind. If the tree bends and regains its original position, and if the planted rootball shows no sign of being pulled over or displaced, it’s safe to remove all staking.

A final word

Tree staking is best done and evaluated by someone knowledgeable and experienced. When it comes to staking, more is not always better, and neither is too-tight or too-loose bracing.

Depending on the size, shape, and crown density of the tree you’re having installed, as well as site conditions, underground anchoring may be better than above-ground stakes.

Professional arborists and tree installers will know the current industry standards (usually referred to as ANSI A300) and the best materials to use for your particular tree.

If you need a tree installed, or if you want to be sure that it’s safe to remove a staking system, give us a call. We love trees and want yours to succeed!

Stake a Tree Properly (How Long to Keep It Staked) | Davey Blog

The new tree you planted is counting on you for enough water, sunlight and nutrients – and it needs a few other elements to succeed, too.

A bit of pruning early on can help your tree establish a good shape. And your new tree may need a bit of literal support, like a stake.

Though, not all young trees need to be staked. Read on to see if you should stake a new tree. If so, learn some staking trees methods and how long to keep a tree staked.

What You Need To Know About Staking New Trees

While it seems like young trees need extra support, most trees don’t need to be staked. Staking trees that don’t need it can cause the tree to grow fewer roots and develop a weak tree base.

Only stake your tree if it needs extra support, protection or help staying anchored.

Should You Stake Your New Tree?

If you properly planted a healthy tree with a sturdy trunk and solid root system, chances are you won’t have to stake it. You also don’t have to stake evergreens, conifers or trees that have branches growing lower to the ground. There are times when you should stake trees, though.

Do Stake:
  • Bare-root trees or trees with a small root ball.
  • Trees planted in areas with lots of foot traffic, like a sidewalk or street.
  • New trees that can’t stand on their own or those that begin to lean.
  • Eucalyptus trees, mesquite hybrid trees, oleander trees and acacia trees.
  • Tall, top-heavy trees with no lower branches.
  • Young trees if you live in a very windy area or if the soil is too wet or loose.

If Your New Tree Needs Staking, Here’s How To Stake It For Support.

  1. Remove the nursery stakes, and find two or three stakes (wooden or metal). Place your hand on the trunk and see where it needs to be steadied. That’s how tall your stakes should be.

  2. Place the two stakes opposite each other and about 1.5’ away from the trunk. Use the third stake only if needed and put on an open side of the tree.

  3. Use a soft material, like canvas strapping or tree staking straps, to attach the stakes. Allow enough slack, so the tree can naturally sway. Don’t use rope or wire, which damages the trunk.

How Long Should You Keep A Tree Staked?

Generally, remove the stake the next growing season. If you add a stake in spring, remove in fall. If you stake in fall, remove in spring. Otherwise, the tree will depend on the stake and won’t stand on its own.

Also, make sure you always remove the wire around the branches! The tree can eventually grow around the wires, which could potentially cut off the flow of water and nutrients.

Learn About Proper Care For A Young Tree After It's Planted.

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Topics:

  • Tree Protection
  • Newly Planted Tree Care
  • Tree Maintenance

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Forest tree fertility and seed collection

Autumn has come and now, along with regularly published data crop yields it is appropriate to provide an overview productivity of forest trees and the possibility of harvesting their seeds.

Text: Esko Krinal,
Head of RMK Nursery and Seed Department
Photo: RMK

Translation from Estonian. The original article was published in the magazine Sinu Mets.


The seed yield of forest trees is unevenly distributed over the years. Just as in our gardens fruitful years for apple trees and berry bushes are not given out one after another, so in our forests fat years for the most important tree species are repeated at different intervals: for warty birch - on average every two years, for pine - 3-4 years and ate, respectively, every 5-6 years.

The volume and quality of seeds is much higher in good years than in poorer years. Therefore, it is best to harvest seeds in favorable years. So we get high-quality seed material at a lower cost.

The purpose of seed harvesting is to pass on the heredity of trees with excellent properties to future generations. Forest crops are established either by direct sowing in the forest, or plants grown from seeds are used and they are already planted in the forest.

Seeds of local forest trees usually ripen in summer in the year of flowering or in autumn. The exception is Scots pine, the ripening of seeds of which lasts two years. And here you need to know not only when they ripen, but also the time and nature of falling off.

Our forests are quite diverse and in them both early and late flowering forms are found in the same species, so the maturation and abscission of seeds occurs over a relatively long period.

Birch seeds ripen first. They reach maturity and fall off by the end of July or the beginning of August. And this year, birch seeds ripened two weeks earlier than usual and began to fall already in mid-July. This year turned out to be very fruitful for the seeds of warty birch, and we often had to clean the seeds that had flown from the windshield of the car in the morning.

Since birch seeds are very light, they are collected in heaps by wind force in windy places, but it is unreasonable to harvest these seeds in this way, since we do not know anything about their origin. Therefore, seeds are harvested from selected trees to ensure that the desired properties of the tree are passed on to the next generations.

Birch seeds are harvested mainly for the cultivation of plants that will serve as the beginning of the future birch forest next year. But the direct sowing of birch seeds and the creation of crops in this way is an unreliable business.

We use about 60 kilograms of birch seeds per year, from which about 2 million plants are grown.

Black alder seeds ripen by the end of October. They fall throughout the winter. This year, alder seed productivity strongly depended on the growing region, and the best results were recorded in South and East Estonia.

Alder seeds are used in the same way as birch seeds: mainly for growing plants. Estonia's annual need for these seeds is 10 kilograms, of which 200,000 plants are grown.


From a forestry standpoint, the most important tree species are Scots pine and Norway spruce. Harvesting pine and spruce cones, as well as obtaining seeds from them, is an important area of ​​work in growing quality forests.

Bud yield is affected by the weather during bud formation and the year of flowering. As a rule, the precondition for the seed year is a hot sunny summer of the previous year. So, for example, we had a record hot summer of 2018. At the same time, late spring frosts can damage yields, rains during the flowering period, insects and pest fungi can prevent pollination. Since everything is balanced in nature, then pests appear when they have enough food.

Pine and spruce seeds ripen in October-November. Their readiness is indicated by a change in the color of the cones. The buds are green at first but turn brown as they mature. According to the color of young cones, two types of ordinary spruce are distinguished: with red and green cones. And when ripe, both of them begin to turn brown. Seeds fall from cones little by little throughout the winter, but massive fall begins with the onset of spring sunny days in March.

A coniferous stand suitable for harvesting seeds must be of quality class II and towers, ripe for refurbishment felling, and the share of harvested tree species must be at least 50 percent. Collected cones should not be free of pests - fungi and insects and not have resin smudges. In the forest, cones are collected in the process of clear felling from felled trees, and in seed nurseries (plantations planted for growing seeds) - from growing trees using a lift.

Seeds are obtained from cones by drying. Cones are kept for two days at a temperature of 45-55 degrees, until the scales open and seeds fall out. Then they are cleaned of fragments of wings, debris and damaged seeds.

A good harvest of spruce cones is expected this year, and below average pine cones.

The previous harvest years for spruce cones were in 2007 and 2013. The latter was particularly successful in Northern Estonia, more or less in Central and Southwestern and not so good in Southern Estonia.

This year there are cones on Christmas trees all over Estonia. At the same time, the peak of the spread of cone pests falls just in their harvest years. The cone leafworm and the cone moth cause the greatest harm. The picture of the damage caused by them is easily discernible by resin secretions, cone curvature and wood dust granules. Such cones should not be harvested - they do not contain a large volume of high-quality seeds.

Spruce seeds are mainly used for growing plants, because when sown, small plants grow that are not able to compete with the grass front on fertile soils, and as a result they die.

The annual need for spruce seeds in Estonia is 400 kilograms. Of these, 15 million plants are grown.

And pine seeds are used both for direct sowing and for growing plants. Direct seeding of pine works well in areas with sandy soils where weak grass growth does not clog pine seedlings.


Estonia's annual demand for pine seeds is 600 kilograms, of which about 12 million plants are grown and 1000 hectares of forest seed are planted.

Over time, the need for seeds has halved. In forests, this is due to the replacement of manual seeding with machine seeding, and in plant production, the need for seeds has been reduced by sowing in covered ground and in pots.

Based on the periodic nature of the yield of forest seeds, their supply for Estonian forests is ensured, taking into account the average amount required for the period between harvest years, in order to guarantee the constant availability of seeds for the cultivation of forests: pine for 4 years, spruce for 8 years and birch - for 2 years. The seed supply is constantly changing: harvested seeds are used and new ones are harvested.


RMK is responsible for securing the seed stock, and the seed stock is handled on a non-profit basis, ie the proceeds from the sale of seeds must cover the costs of harvesting and storing them. Seed harvesting is ensured by RMK with the help of its employees in order to guarantee the reliability of seed origin and compliance with the requirements stipulated by legal acts.

We currently have a stock of pine seeds for 5 years, spruce for 9 years and birch for 4 years, which ensures the stability of Estonian forest renewal.

Wood is the material of the future, which, if used correctly, can be used to produce durable products

wooden buildings. Thanks to advances in science and new technologies, we have learned to produce ever higher quality materials and are able to do the best how to use the wood that we get from the forest. And to find even more sustainable solutions for the use of wood, and even with greater added value, including the use of opportunities hardwood, which is still little used, it is necessary to find out what determines the quality of wood and the possibility of using it in production. The basic principles of dendrology are explained by the professor Tallinn Technical University Jaan Kers.


Text:
Christie Parro
Photo: Scanpix, Christie Parro, Valmos (EMPL)
Material published in the RMK Metsamees 9000

with Jaan Kersa TALTEN . We walk through the laboratories, talk about projects in progress and how students, through science and developing practices, get acquainted with the possibilities and features of using wood. The fact that learning takes place through practical activities is evidenced by a bookcase along the wall, a sofa for guests standing at the front door, a three-dimensional wood picture on the wall, as well as other pieces of furniture designed and made by students in various rooms of this building.

It turns out that the material Estonians love – wood – requires a lot of attention in their work, and design mistakes are very difficult to correct.
“The quality of wood dictates what can be made from it. And the quality itself depends on where the tree grew: on the seven winds, on the coast, on the mountainside, on limestone or sandy soil, how fast it grew and what kind of tree, in a word, on many factors, explains Professor Kers. “Today, we mainly use coniferous wood as a building material. Pine and spruce have even, straight trunks, uniform annual rings, and something can be made even from a thin tree. And we need to make more use of hardwood.”

The scientist adds that hardwoods are growing faster and in the future, given the warming climate, the proportion of these species in Estonia will probably be higher. But at the same time, hardwood will be more crooked than softwood, it is more knotty and more susceptible to disease.

Internal stress

Kerse takes two books on dendrology from the shelf and starts by showing a drawing showing the core of a tree. “For the first 10-20 years, a coniferous tree grows quickly and the annual rings are such that there are a lot of spring wood and little autumn wood,” the professor points out the annual rings in the early stage of tree development in comparison with the later part of its growth. “In our country, such a big difference is especially clearly manifested in trees that have grown in abandoned fields, hayfields and fallow lands.”

It turns out that the heartwood, the early wood surrounding it, as well as the heartwood rays going from the center to the bark, are the weakest part of the tree. The fact is that in a young tree, cells divide quickly and they do not have time to grow long. And in the process of drying the tree, it is this part of it that contracts the most, the cells of the core rays are torn from internal stress and cracks appear.

“The faster the wood dries, the greater the internal stresses and the larger the cracks. This is what they try to avoid when drying wood.” And although they are weak, there is also a reason for the existence of core rays - nutrients move along them in a horizontal direction, and when we chop wood, the log cracks more easily exactly where these rays pass.

Measure seven times . ..

“If you cut a tree in this way,” Kers takes a board on which annual rings are clearly visible, “we see that the lighter part of the spring wood consists of large cells, so that they could pump the maximum amount of water and nutrients up.”

In autumn wood, the cells are smaller and thick-walled, they give mechanical strength to the wood. And they're up to three times stronger than thin-walled springwood cages and better able to resist wear and tear, Kers explains why it's important to saw wood properly, given what the planks will go into and how they'll wear with use.

„If the floorboard obtained by the radial sawing method wears out, then the part of the spring wood located between the two autumn annual rings is somewhat worn out. In this case, abrasion is not as noticeable as with boards obtained by the tangential sawing method, when the material is taken from the sapwood side, that is, the younger wood of the trunk, says Professor Kers. - The most wear-resistant material is obtained precisely from the middle of the trunk - this is heartwood. By sawing the wood correctly, if the wood fibers are straight and not heeling, and using the correct drying regime, we get dry lumber that does not buckle or bend.”

The professor gives an example of the old floorboards on the manors - they are even and there are rarely gaps in them. The only problem is they wear out. “For wooden floors, good maintenance, varnishing is very important so that depressions do not form in the floor. Otherwise, on tangential boards, for example, the annual rings begin to diverge, and the boards will peel off.”

Should felling depend on the season?

“If you harvest wood at a time when the nutritious juices flow through it, that is, in the spring, then you must remember that the sapwood is less resistant to pests and fungi,” explains Mr. Kers.

Sapwood is the part of the tree where nutrients and moisture are actively moving, especially in spring.

“When juices and glucose enter the cells of the tree, it's time for fungi and pests to get food there,” explains Mr. Kers. - The weather also plays its role: if it is dry, hot, then the blueness of the wood appears more easily. Therefore, during spring felling, it is important to put the wood into action as soon as possible.”

Use wood to extract minerals

If sap flows in the spring - we collect birch or maple sap ourselves - then in winter the sap does not move, it is accumulated in the root system. When I ask how this affects the composition of the forest stand that is cut down, my interlocutor's eyes light up: “It would be very important to investigate. If you cut down two or three trees in the same place, but at different times of the year, you can find out what is the effect on the chemical composition of wood, its strength, what metals contain trees grown in different places, say, zinc, cadmium, lead , copper?".

I'm asking, does it mean that we can extract non-ferrous metals in years when there is no logging? Kers doesn't mind. Each type of tree, they say, has its own periodic table, which constantly moves between the root system and various parts of the tree, but the amount of non-ferrous metals in wood is very small.

“The characteristics of a tree may differ depending on the place of growth - whether it is limestone soil, as in Northern Estonia, or sandy, as in Southern Estonia, and depending on the time of year. It is imperative to conduct a study of the mechanical properties of the forest stand and its chemical composition growing in different regions of Estonia. Such studies have already been carried out in Finland, Sweden, Norway. At the same time, they have the opportunity to compare the properties of wood, with a growth difference of 1000 kilometers.

“For Estonia, of course, this is a large-scale and complex project, in which it is necessary to determine the exact methodology for selecting the habitats of experimental trees, as well as the system for sawing wood, selecting the drying mode, so that the results of the experiments are comparable,” says Professor Kers. “To implement it, the cooperation of scientists from TalTech and the Estonian University of Life Sciences with enterprises, RMK, the Association of Private Forest Owners and other organizations is necessary.”

The place of the knot leads to new solutions

Kers believes that the driver of innovation in the woodworking industry is the consumer, who wants clean and smooth surfaces and at the same time an environmentally friendly product. And here a good example is wood glued onto a jagged spike.

“Many factors can affect the quality of the final product,” says Mr Kers. – Take, for example, the places where knots are cut on a tree. If you putty this place inside a window or doorway, then this is inconvenient. And this place from under the white paint is still knocked out with a yellowish tint due to the presence of resin. In any case, the place of the knot will be visible.”

According to Kers, the problem was solved by using different plastic caps that do not have knot problems. At the same time, the woodworking industry learned how to produce knotless wood, began to use splicing on a toothed tenon, with such material there are no problems with puttying and looking through the cut of a knot.

“The technologies we use are becoming more and more sustainable, but there are also new challenges: how to properly use hydrophilic wood, a material that loves moisture?” the professor asks. The fact is that we have now switched from solvent-based wood protection systems (for example, biocytes and wood protection agents) to water-based systems.

“The first layer of impregnation, which is applied to wood, does not penetrate deeply, remains on the surface, does not “penetrate” even a millimeter. But the water-based treatments, those raise the wood fiber. Solvent-based treatments don't attack wood fibers as aggressively as they cause the wood surface to swell,” Kers explains.

But he believes that there is a way out here too: it is necessary to carry out intermediate sanding so that the surface of the wood does not become rough. And he adds that the tree does not forgive if it is misused.

Is any piece of wood good for building?

Again, we are talking about cages and growing trees, that any piece of wood can not necessarily be used in construction. “Here it is perfectly clear that in place of the compressed annual rings, the content of lignin is higher,” Kerst points out to the so-called reaction wood. So the tree responds to one-sided pressure, such as wind, or will begin to grow autumn wood, as it grows on a mountainside. Indeed, from the cut of the tree it is clear that on one side the rings of autumn wood are wider and better visible, and on the left side they are narrower.

“It is impossible to get a good board from such wood, there will be bends, the material will be uneven after drying. Sawmills try to identify the part of the reaction wood in the lumber to avoid quality problems later, explains Mr Kers. – In reaction wood, the length of the fibers is different, in the lower part they are shorter and compressed, and in the upper part they are elongated, therefore longer. And traction hardwood becomes fibrous during sanding, it is not so easy to make it smooth.

Because of the reactive wood, tree branches, no matter how thick, are not very suitable for the production of furniture and wood products.

But reactive wood is an obstacle even in the production of quality paper, when the wood fibers are converted into fine-fiber pulp in a chemical process. In such wood, the fibers are of different lengths, so it is impossible to obtain fibers of the same quality in order to make strong and high-quality paper. “Therefore, fast-growing hardwoods are best suited for printing paper because they have uniform, short fibers. Softwoods are good for making high-strength wrapping paper (kraft paper) as well as strong material,” Kers explains.

Most printed paper today is made from chemical pulp, which is made from eucalyptus wood. Relevant factories are located in South America and Asia.

Wood is the future

“Wood is the only renewable natural resource in Estonia that we can use in construction,” says Mr Kers. – We talk a lot about the fact that we use almost 100 percent of the incoming wood at the plant, but this is only raw material. Where does the energy used in production come from? When talking about green manufacturing, we have to consider the whole process so that the whole process is green.”

We have come to the conclusion that a lot has already been done for the benefit of the environment. Wood gets added value and the possibilities for increasing it are almost limitless. But in scientific work one should not forget about the process as a whole. We agree with Mr. Kers that in the near future we will talk with him about adding value to wood.

Wood Processing Technology Laboratory