How to tell if the tree looming over your house and in your thoughts is a hazard tree…
It’s big and it’s heavy, and it’s got the potential to put a major dent in your home and your finances…but is it truly a hazard tree? When should you worry? And when should you simply be grateful for the extra shade?
Trees lay across a roof after a windstorm
We at Sand Creek Tree Service are experienced in assessing hazard trees. That said, not all problem trees are readily detected. Sometimes the structural defects are hidden inside the tree or below the soil. Sometimes, a “better safe than sorry” approach is best. We’ll always discuss options with you, letting you make the final call when it comes to potential risks that are hard to quantify.
However, many hazard trees present signs of their structural weaknesses. Ultimately, a hazard tree is one in which the weight of a tree – or a part of the tree – exceeds the tree’s structural integrity (in a branch, trunk or roots). When assessing your tree for risks, we evaluate the likelihood of the tree failing, the environment that contributes to failure, and the target (the part of your property that would sustain damage).
There are seven general problems that point to your tree being a hazard tree: decayed wood, cracks, root problems, weak branch unions, cankers, poor tree structure, and dead portions of the tree. Decayed or rotting wood is often indicated by shelf mushrooms – a parasitic fungus – growing on the trunk. Cracks are often obvious and can be the result of lightning, frost, or other factors. Root problems might be evidenced by a bulging in the ground to one side of the tree, indicating that anchor roots are slowly losing their capacity to hold the tree in place. Weak branch unions can appear as a kind of seam in the bark, a sign of included bark. This means the branch is not fully connected to the rest of the tree; as the limb grows over the years and increases in weight, that union my fail. Cankers will look like a bulge or deformation in the trunk of your tree, meaning that the bark and cambium layer are dead and nutrients aren’t flowing through the tree as they should. Poor tree structure simply implies that your tree has grown in a direction or manner that makes breakage more likely. Perhaps the tree has a heavy lean, or maybe a horizontal branch has acquired too much weight. Finally, a hazard tree is most obvious when it is dying (dead top or branches) or completely dead.
Besides looking at these seven factors, we also assess the direction of prevailing winds in your area and which direction your hazard tree might fall. Another important factor to consider is the target. What will the tree damage when it falls? If you have a hazard tree without the potential to damage your property or injure anybody, we sometimes suggest letting nature takes its course. Trees that humans deem hazardous can make for important animal habitat. Think of all our local eagles and osprey that nest in snags.
If a potential hazard tree is regularly invading your thoughts, don’t hesitate to give us a call. It’s better to bring down a tree in a controlled manner – especially around people and structures – than to let your roof bear the brunt. And who knows, maybe your tree is perfectly healthy and willing to provide you and your family shade and birdsong for another fifty years. But a little peace of mind provided by a professional is always worth the effort.
Weak branch unions are easy to spot before they become a problem…
Weak branch unions are one of the most common hazards we see on clients’ properties. This hazard is easily identifiable and, thus, easily avoided. But what are the signs that tell us a weak branch union likely exists?
The most frequent weak branch union we see is called a co-dominant stem. This is where two stems of roughly the same size arise from the same point on the tree. (This is also known as a “schoolmarm” in forestry circles…but it’s up to you to learn the backstory on that.) The junctions between co-dominant stems are often considered the weakest portion of a healthy tree. They are widespread in forested areas; you’ll often see them on area trees, especially ponderosas. It will look like the tree has two or more tops. This creates a weak branch union because the two stems, or leaders, are growing so closely together that the bark on each leader interferes with the formation of a proper, strong union. This is called included bark, and it doesn’t have the structural strength of a normal branch crotch. Furthermore, included bark can act as a wedge, forcing the weak branch union to split apart.
Removal of a ponderosa with co-dominant stems earlier this spring. Weak branch unions are especially troubling near structures.
During the windstorms of recent years, we’ve seen countless trees lose one of their co-dominant stems. Wind will point out any weak branch unions you have, if you’d rather not pay a professional to investigate. The problem doesn’t stop with the toppling top of the tree—and subsequent property damage—though. Once one of the co-dominant leaders is gone, a wound remains and leaves the tree structurally weaker and vulnerable to infection. The best approach is to be proactive about trees with co-dominant leaders. Either remove one of the leaders in a controlled environment, or cable the two stems together so they support one another and don’t sway past the trigger point in the wind. We are well versed in both approaches and can talk you through options.
Another example of a weak branch union is when epicormic branches (also known as watersprouts or suckers) are allowed to grow into sizable limbs. Epicormic branches grow quickly—often in response to poor pruning practices, injury or some kind of environmental stress—and they always display weak branch unions. It’s best to tend to suckers when they are newly formed, before they pose any real hazard to structures and people.
Finally, any branch that comes off the trunk at a very acute angle or doesn’t display a ridge of raised bark at the crotch is of potential concern. If you have trees on your property that exhibit any of the signs of a weak branch union, call us for a free consultation and estimate. Considering the widespread impacts of recent windstorms—and the fact that weak branch unions are especially susceptible to failure in wind—a call to us will at least provide peace of mind.
At least once a month, we get a request for topping someone’s trees. The reasons are myriad: The tree is blocking the view, it’s impinging on satellite service, it’s deemed too tall and hazardous, or someone just likes the look. On the surface, topping doesn’t seem like a bad idea. You get to keep your tree and have it out of your way. In reality, though, topping is a terrible practice, and we try to dissuade all our clients from having it done.
These Norway spruce trees will be unable to heal over the wounds that topping created, thus leading to rot and structurally unsound trees.
Why is topping so bad? There are a lot of reasons, but first and foremost is that it will likely kill your tree. Hacking it back may not kill it this year or next, but your tree’s lifespan will definitely be shortened.
Topping drastically reduces a tree’s leaf mass, limiting the tree’s ability to produce food and sustain itself. This causes root dieback. Also, the site of an indiscriminate topping cut can provide access to decay, insects, and disease. And limbs newly exposed to sun without the protection of the canopy may become sunburned, leading to cankers and branch death. All of this leads to an unhealthy, unstable tree.
Furthermore, topping often leads to something we call “witchbrooming.” This is where a multitude of branches sprout from near the cut. These epicormic branches are weakly attached and can grow up to 20 feet in one year. Such limbs are susceptible to breakage in storms, causing more damage than the tree originally would have.
Another problem with topping is that it will ultimately cost you more in the long run. More frequent pruning will be necessary to mitigate branch failure risks and to rein in the height of the new epicormic branches. Furthermore, as the tree’s health declines, it may just have to be removed after a number of years.
It’s no surprise that such extensive topping killed this tree. If you want to cut a tree back that much, it’s better to just remove it entirely.
Finally, topped trees are ugly. When you consider that healthy, well-maintained trees can add 10-20 percent to the value of your property – and topped trees can be seen as a safety risk – why would any homeowner request the practice?
However, there are healthy approaches to canopy reduction. One method is called “drop-crotching,” where tall limbs are cut back to an appropriate branch that can take on a terminal role. This branch must be at least one-third the size of the one removed. Drop-crotching can diminish height while maintaining the shape and health of a tree. However, this is only appropriate for trees with a rounded, or decurrent, shape. Pyramidal, or excurrent, trees (think conifers) simply cannot have their height reduced without negative consequences.
In some cases, the best practice is to remove the problem tree and replace it with one better suited to the site.
If you are considering topping your tree, please give us a call. We can offer alternative approaches that may solve the problem at hand.
Utilizing proper pruning techniques can save you money down the road…
Many of the big, expensive jobs that come our way are the result of improper pruning practices. Though these expensive jobs are good for our bottom line, we’d rather see our town populated with healthy, thriving trees, the result of proper pruning.
This tree was once topped, and it has now sprouted back with a vengeance. These epicormic branches tend to be weakly attached to the tree, causing problems with falling limbs later.
Why is proper pruning so important? And why does improper pruning lead to expensive remedies? Improperly pruned trees cause excessive wounding and resultant rot, decreased food production which weakens the tree, increased sprouting that leads to weak branch unions, and increased chances of wind, ice, and sun damage. Thus, a tree that is not properly pruned is more likely to die or to drop limbs. These limbs—or the entire tree—must be removed, at a greater cost to the tree owner than properly pruning at the outset.
The most common improper pruning practice we see is the topping of trees.
These topped trees are unlikely to survive long. Such drastic pruning practices are never acceptable.
This is where the limbs are cut back close to the trunk in order to decrease the height of a tree. Many people do this in order to improve views or satellite reception, to decrease shade in the yard, or to get rid of some of the “mess” that trees create (leaves, fruit, etc.). In all of these situations, we recommend simply removing the tree. It is better for the tree—and your bottom line—to cut it at the base than to leave it weakened and dangerous.
The International Society of Arboriculture has several brochures on the proper pruning of trees; Pruning Mature Trees and Pruning Young Trees are both worth looking at if you’re considering taking on tree pruning yourself. However, if you have any trepidation about tackling a pruning project, don’t hesitate to call us. It’s much less expensive to properly prune a tree than it is to remedy the damage done by improper pruning practices.
Weak branch unions are one of the most common hazards we see on clients’ properties. This hazard is easily identifiable and, thus, easily avoided. But what are the signs that tell us a weak branch union likely exists?
A tree with two tops – or co-dominant stems – indicates a weak branch union and, thus, a hazard.
The most frequent weak branch union we see is called a co-dominant stem. This is where two stems of roughly the same size arise from the same point on the tree. (This is also known as a “schoolmarm” in forestry circles…but it’s up to you to learn the backstory on that.) The junctions between co-dominant stems are often considered the weakest portion of a healthy tree. They are widespread in forested areas; you’ll often see them on cedars, ponderosas and hemlocks. It will look like the tree has two or more tops. This creates a weak branch union because the two stems, or leaders, are growing so closely together that the bark on each leader interferes with the formation of a proper, strong union. This is called included bark, and it doesn’t have the structural strength of a normal branch crotch. Furthermore, included bark can act as a wedge, forcing the weak branch union to split apart.
During last summer’s windstorms, we saw countless trees lose one of their co-dominant stems. Wind will point out any weak branch unions you have, if you’d rather not pay a professional to investigate. The problem doesn’t stop with the toppling top of the tree, though. Once one of the co-dominant leaders is gone, a wound remains and leaves the tree vulnerable to infection. The best approach is to be proactive about trees with co-dominant leaders so that you lose one of the leaders in a controlled environment – and save the tree in the process.
Another example of a weak branch union is when epicormic branches (also known as watersprouts or suckers) are allowed to grow into sizable limbs. Epicormic branches grow quickly – often in response to poor pruning practices, injury or some kind of environmental stress – and they always display weak branch unions. It’s best to tend to suckers when they are newly formed, before they pose any real hazard to structures and people.
Finally, any branch that comes off the trunk at a very acute angle or doesn’t display a ridge of raised bark at the crotch is of potential concern. If you have trees on your property that exhibit any of the signs of a weak branch union, call us for a free consultation and estimate. Considering the widespread impacts of last year’s windstorms – and the fact that weak branch unions are especially susceptible to failure in wind – a call to us will at least provide peace of mind.
