Hazard Tree Assessments

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 house roof after a wind storm
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.

For more information, check out this excellent hazard tree graphic.

And the city of La Grande, Oregon, has a good hazard tree checklist.

Winter Tree Care Checklist

You know how to handle the cold season, but is winter tree care on your radar?

By this point in the winter season, many of us feel like we’ve got it all figured out. We’ve worked out the snow removal kinks, have all our firewood in, and know how to keep our family and animals cozy and safe. But what about winter tree care? Has that crossed your mind?

winter tree care

If you’re like most people, unless you’re dealing with broken limbs, probably not.

So, what does winter tree care involve? Thankfully, there’s not much to it, but these few key points are important.

Root protection
The first consideration for roots is insulation. In the Sandpoint area, this is usually not a problem. We get enough snow to insulate roots from cold temperatures. However, it’s still not a bad idea to mulch around the base of your trees for added protection. After the snow melts, get ready for next winter by spreading a two-to-four-inch layer of mulch around the base of your tree, under the canopy. Just be sure to keep mulch away from the trunk.

The other consideration for roots that is an issue in Sandpoint is the use of road salt. This can cause discoloration of foliage in evergreens and bark dieback in all trees. In the long term, it can lead to systemic issues caused by the preponderance of salt in the soil. Several options exist to remediate this issue:

  • Use calcium chloride instead of sodium chloride. It’s more expensive but less harmful to plants. And when you consider the cost of a hazard tree removal, it may be more cost effective in the end.
  • Furthermore, you can mix your road salt with sand for added traction and to lessen the amount of salt used.
  • Extra watering of roadside trees can dilute the amount of salt present on the trees and in the soil.
  • Finally, apply gypsum in late fall, before snow comes, to protect roots.

Trunk protection
Especially on young trees, thin bark is a vulnerability. Deer can do damage by rubbing their antlers on the trunk. Rodents can tunnel through the snow and chew the bark. And even temperature swings can do damage, warming the trunk on a sunny day, only to freeze hard at night, damaging a vascular system that got excited about spring. An easy winter tree care solution to these problems is to wrap the trunks—from the base to the lowest branches—with plastic tree guard. This is especially important for young maple, ash, linden, locust, dogwood, cherry, birch, and crabapple trees.

Branch protection
The best protection for branches is maintenance pruning. This ensures that broken and diseased branches are removed before the snow does it for you. At this point in the season, though, proactive care can include gently removing snow from drooping branches to prevent them from breaking. Do this with a broom rather than by shaking the limb so as not to harm the branch. Also, try to keep from piling snow against your tree, trapping low branches in the process. And finally, if you notice ice covering your tree, leave it. Let it melt and then inspect for damage. Trying to remove ice yourself will likely cause more harm.

With these few tips in mind, your tree should easily weather the winter. Come spring, if you notice any damage from the cold season, call us. We’re happy to assess your tree’s health and suggest any corrective action it might require.

Dieback in North Idaho’s Fir Trees Explained

Rampant dieback is evident in area trees, but why?

This year, many of us noticed conifer dieback —especially affecting fir trees—on our properties and in our surrounding forests. The flaring out (or reddening) of so many trees is alarming to those of us familiar with bark beetle infestations elsewhere, including those decimating entire hillsides in Montana and Colorado. Are our tree stands doomed, too?

The thing is, bark beetles aren’t to blame for what we’re experiencing here; they’re just finishing off a job begun by other factors. The fir dieback we are now seeing actually has its roots in a century’s worth of logging, fire suppression, and the introduction of pathogens like white pine blister rust. This all contributes to more grand fir, Douglas fir, and subalpine fir than North Idaho has traditionally supported.

Next, the hotter, drier summers of recent years have stressed out our trees, leaving them more susceptible to diseases and pests. Thus, pathogens that healthy trees can easily fend off are now flourishing amidst weakened “immune systems.”

One such problem is the myriad native fungi that lead to root rot. Doug fir, grand fir, and subalpine fir are the species most susceptible to root diseases, and these diseases alone—even without the beetles—are leading to massive dieback.

Since the fungi responsible for root rot live in the soil and remain onsite through generations of trees, this problem isn’t going away anytime soon. However, even in the face of drought, there are things a landowner can do to diminish the threat of dieback. The first step is to thin the forest so trees aren’t competing for water and nutrients. Twelve to fifteen feet between saplings (more for larger trees) is a good rule of thumb. The second step is to ensure forest diversity, including a majority of trees tolerant of root diseases. These include (in descending order): ponderosa, Western larch, Western red cedar, lodgepole pine, Western white pine, Western hemlock, and Engelmann spruce.

Fir trees sometimes struggle and survive at the brink of dieback brought on by drought and root diseases, but opportunistic beetles exist to finish off the job. In North Idaho, we have over 100 species of bark beetle, each specializing in different conifers and sometimes even different parts of specific conifers. These beetles are a natural part of our forest, but they are flourishing right now due to the aforementioned factors of drought, overcrowding, fir population imbalances, and root rot.

If you notice fir dieback (or other struggling trees) on your property, give us a call. We can provide an assessment of your trees and forest and how best to tackle the domino effect that runs from drought to dying trees.

For more information on area tree diseases, check out “A Field Guide to Diseases & Insect Pests of Northern & Central Rocky Mountain Conifers.” To learn more about root diseases in particular, visit “Root Diseases in Coniferous Forests of the Inland West.”

 

Root Problems: The Most Difficult Hazard to Detect

Root problems might be simmering under the forest floor, waiting to topple your trees…

Root problems are the most difficult hazards to detect because most of the problem is underground and out of sight. People often have to wait for the visible portion of the tree to be affected before determining that there are root problems. Above-ground signs of root problems might include dieback, discolored needles or leaves, leaning with recent root exposure, as well as soil heaving, conks, or sap flow near the base of the tree. Also, failing trees nearby could indicate that the still-thriving trees might have a root problem.

Roots are essential to the structural support of your trees. They literally hold your tree to the earth. Thus, when root systems begin to fail, trees become a hazard to nearby people and property. Root problems may lead to blow-down in windstorms or tipping over without warning under the weight of leaves in the summer. Root problems are often silent but carry deadly consequences.

root problems

Decay fungi often indicate that a root problem is present.

There are two types of root problems: physical and biological. Decay fungi often cause biological root problems. This becomes evident when conks appear near a tree’s roots and in nearby decayed stumps. However, only about half of the trees infected with root rot might show symptoms at any one time. In this region, grand fir and Douglas fir are particularly prone to laminated root rot. Idaho Department of Lands provides an excellent and informative explanation of laminated root rot.

Physical root problems are often human-caused. They include severed, loosened, cracked, broken and exposed roots. Construction or paving near a tree, driving vehicles over roots (soil compaction), and raising or lowering the soil level near a tree can all cause physical root problems. In attempting to diagnose a failing tree, we may ask you questions about recent activity on your property. If you’ve just constructed an addition to your house or have rerouted your driveway or plumbing, that might be the problem.

One final physical root problem that is not human-caused is the girdling root. These roots grow around or across the trunk or other roots on the tree. As the tree grows, girdling roots may begin to choke the tree, reducing its ability to take in water and nutrients. Symptoms are similar to those you might see in drought, including early fall color and dieback.

Of all of these issues, the symptom you should be most concerned about is a tree demonstrating an increased lean with cracking or mounding soil at the base. This is a serious hazard and should be dealt with immediately, before it falls on its own…because it will soon fall. Even if you only suspect root problems in one of your struggling trees, give us a call. We’re happy to provide an assessment and free estimate.

For more information about root diseases, go to the Forest and Shade Tree Pathology website. And to learn more about your potential hazard trees, don’t hesitate to contact us.