Mar 9, 2015
If decayed wood is visible on your tree, is it always a hazard? How do you know if there is decayed wood that you can’t see?
As mentioned in our previous post, there are seven general problems that point to your tree being a hazard tree, and decayed wood is one of them. Hazard trees are definitely still on peoples’ minds these days with the pair of storms we sustained this summer. Many of us experienced tree loss and breakage – some with resultant property damage – and all of us (even the lucky ones who didn’t lose trees) are wondering which trees might go next. We’re only now, months after the fact, getting caught up on cleanup and precautionary tree pruning and removal related to the storms. Those wind events left major impacts on our properties and our psyches.
In order to answer lingering questions and assuage fears, we’ll cover all the different hazard tree indicators over the next few months. Today we’ll start with decayed wood. Decay is probably responsible for the largest percentage of tree failures (though, honestly, those windstorms blew a lot of conventional wisdom out the window; we saw many seemingly healthy trees simply uproot). While decay is not always visible from the outside, there are several reliable indicators of internal decay.
One indicator of decayed wood is rot fungi.
One indicator is the presence of conks, brackets or mushrooms sprouting from the tree. This is a definitive sign of internal rot and should be taken seriously, especially if the fungi appear on the trunk or visible roots. Different fungi signify different kinds of rot. White rot reduces wood’s stiffness, while brown rot (common in conifers) makes the wood more brittle. Soft rot can lead to both of these deleterious effects. All of these kinds of rot reduce a tree’s structural strength.
Open cavities also signify rot. It’s important to explore the depth of a cavity to determine the extent of decayed wood. However, it’s never advisable to fill the cavity with any kind of “strengthening” material or to excavate the decayed wood from the hole. More harm than good comes from both of these approaches. Sometimes – as with many kinds of decay – trees are able to compartmentalize the cavity, containing it and halting progress. Our interventions only hinder this process. With other kinds of decayed wood, a tree might attempt to outgrow it, adding more layers of strong, healthy wood to stabilize the weaker portions.
Carpenter ants and their resultant “sawdust” at the base of a tree are another good sign of decayed wood. Other potential signals are cracks, bulges, loosened bark, oozing, and both old and open wounds, all of which should be inspected further to determine the extent of possibly decay.
Sometimes, no sign of decayed wood is visible; even the canopy may appear full and green. However, if you have any reason to suspect there is silent decay going on inside your tree, share your concerns with us. We can talk about the history of the tree and its care and maybe even pound on the trunk from a few different places (something known as “sounding”) to get a sense for what might be gong on inside.
Decayed wood doesn’t always mean the tree must come out. Perhaps some selective pruning will mitigate dangers, or maybe a lack of targets (i.e., houses, outbuildings, landscaping, etc.) means the tree is free to live out its natural life. Ultimately, it’s up to you, the landowner, to make the final decision on the level of risk you’re comfortable with. On our own property, we live with a certain level of risk because we so value the big, beautiful trees circling our home.
If you have any concerns about decayed wood, don’t hesitate to give us a call. We’ll do our best to help inform you in your
Mar 8, 2015
How to tell if the tree looming over your house and in your thoughts is a hazard tree…
Let us help you determine if your tree is a hazard before it does this.
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?
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.
Mar 7, 2015
When to attend to much-needed tree pruning…
The best time to prune is now. Don’t delay attending to your tree’s health.
It’s a common question among our clients: When is the best time for pruning my trees? And it’s a question with as many answers as there are people who care to comment. There are kernels of truth to ideas that some trees prefer pruning at some times over others, and that pruning at various times of the year produces different effects. However, the answer can generally be kept fairly simple: When you remember that your tree needs pruning, that’s when you should do it. Your tree is healthier pruned, no matter the time of year.
Removal of dead, diseased or problem limbs can be undertaken at any time without negatively affecting the tree. This makes up the bulk of pruning requests. Sometimes, though, people simply want their tree cleaned up and thinned out a bit (and kudos to them for seeing the importance of such maintenance!). Attending to this in late winter or early spring – before the buds swell – will maximize growth in the coming year. Conversely, pruning during or soon after the leaves come out can retard growth. The tree has just expended most of its energy in putting out new shoots and leaves, so it has few resources left to compensate for what has been removed. Normally this isn’t a problem, but if too much is removed during this time of major energy output, the tree can become stressed and, thus, more susceptible to disease.
Pruning when the tree is dormant – after it has lost its leaves and before buds swell in the spring – allows the tree the most time and energy for healing its wounds. It gets a full growing season to compartmentalize those pruning points. Furthermore, at the time of pruning, pests are also dormant and won’t use the wounds as points of entry.
Fruit and other flowering trees can be pruned at various times to various effect, depending on your desire to enhance flowering, develop proper structure, or thin fruit. Other trees may be susceptible to certain pathogens that follow particular transmission schedules, so pruning is generally avoided during this time.
All of this aside, though, we can’t emphasize enough that one of the most important things you can do for the health of your tree is to keep it properly pruned. No matter the tree, no matter the season, if you look out your window and are reminded that your tree is in need of a little TLC, give us a call. We will come out and assess the tree, as well as provide a free estimate. If we determine the tree would be best left alone for a few weeks before pruning, we’ll let you know. Just make the call. Your tree will thank you with a long and productive life.
Mar 6, 2015
Springtime, pines, and Western gall rust…
Newly emerged galls on a lodgepole branch.
‘Tis the season for Western gall rust. Just when the earth is emerging from its blanket of snow and little green shoots are appearing, so, too, do galls. Right now, take a look at your ponderosa and lodgepole pines; see any pale-colored, bulbous growths on the branches? If so, you’re looking at the emergence of galls, full of spores that are ready to set sail on the winds. Is this something to worry about? Well, that depends. First, let’s learn a little about Western gall rust.
Western gall rust is caused by the rust fungus Endocronartium harknessii. It is unique in that it doesn’t require an alternate host to complete its life cycle (with other rust fungi, like white pine blister rust, an alternate host – like gooseberry – is required to pass the fungus along). This means Western gall rust can spread easily from tree to tree via airborne spores without the assistance of an insect or another plant. Thus, if you see galls in some of your trees, it’s likely it will spread to others nearby.
Western gall rust affects trees of all ages. The younger the tree, though, the more damage it does.
You can identify galls most easily in the spring when they take on a pale yellow to orange color. They appear as small, pear-like objects growing on the limbs or sometimes the trunk of the trees. Galls on the trunks of larger trees create what’s called a stem canker, which looks like an ugly, deformed crack. It rarely kills the trees directly, but it can weaken the structure of the tree and make it susceptible to breaking in a wind event or heavy snow. Galls growing on limbs will eventually girdle the limb and kill it. A tree with too many galls in the crown will have a difficult time photosynthesizing as all the live branches begin to die back. Without sufficient photosynthesis, the tree’s health spirals into decline. In saplings, galls on the trunk are usually fatal as they girdle the tree and prevent the flow of water and nutrients.
Pruning limbs with galls before spore generation – ideally in the fall and winter months – will help reduce the rate of spread throughout the tree and to other trees. In addition to lodgepole and ponderosa, keep an eye on your ornamentals like Mugo, Austrian, and Scotts pine. They are also susceptible.
Ultimately, Western gall rust is a part of life in the forest here. It’s been around just as long as its host trees have been, and our ponderosas and lodgepoles still thrive. However, your yard is a managed landscape, and with that management comes the responsibility to keep an eye on the health of your trees. If you’re concerned about Western gall rust, give us a call. We’re happy to assess the vitality of your trees.
For more information about Western gall rust, check out this page from Washington State University, “Garden Friends & Foes.”