I get lots of pictures of sick trees. The first image that is typically sent to me shows a declining canopy Maybe a picture of an ugly leaf. After all, when we occasionally cast a glance upward at the living giants that provide shade for our parks, yards, and homes, that is typically what we first notice.
Before beginning any kind of diagnosis of the ailing tree, there is one thing I always ask a client for: a picture of the base of the trunk as it protrudes from the ground. Because I tend to find the majority of the issues in large shade trees here, this portion of the tree is crucial.
Look at the base of the trunk when you are walking through a forest or park with more mature trees. Most likely, the trunk will flare out at the base. This is called the root flare. The trunk and root flare of trees must be above the soil line despite the fact that their roots are adapted to being buried in the ground. The tree is too deeply planted if it resembles a telephone pole sticking out of the ground.
Please be aware that most trees are already too deeply planted in their containers when you buy them. In many cases, you will need to carefully remove the top few inches of soil from the pot in order to see a clear flare or the first structural root As young trees, some species, especially evergreens, might not have a distinct root flare. At that point, use the first structural root as a guide.
Planting a tree too deep does not equal immediate death. Few things kill a tree instantly besides a chainsaw. A tree that is planted too deeply will have a shorter lifespan because its roots will flare and any exposed trunk will rot over time. Maybe it will last 10 to 20 years as opposed to a 200-year-old oak. Not bad given the typical American home ownership period, but not great given the potential lifespan of the oak
It is recommended to mulch young shade trees. I would argue large ones benefit from mulch too. It deters lawnmowers and string trimmers, lessens turfgrass competition, and creates a defined, aesthetically pleasing space around the tree. However, how and what we use as mulch can determine whether a tree is healthy or not.
As a landscaper, I mulch trees with tons (literally) of decorative gravel. People like the way it looks, and you can simply spray some weed killer on any weeds to kill them. Sounds simple, from a designer’s point of view. However, from a horticultural perspective, rock mulch does not improve the plant’s health. In some cases, it can even make the environment less favorable for the tree. Even though the rock doesn’t break down like wood mulch, it still settles into the ground and can be difficult to remove if you ever need to. Some will place plastic underneath to prevent this. Which is another practice Extension does not recommend. Air and water cannot reach the tree roots below the mulch because of the plastic. Additionally, isn’t there already enough plastic in the world?
Because they are usually coarse and don’t pack down like some shredded wood mulches, arborist woodchips are a suggested kind of mulch. These are often readily available in Illinois. When I can’t get my hands on arborist woodchips, I use shredded wood mulch because it’s not a bad substitute. I also love using shredded autumn leaves, and I did so a lot at my previous house.
It is frequently advised to lay landscape fabric as an underlayment beneath mulch. This tactic has merit because, at least for a few years, this fabric can reduce the amount of weeds that grow through your mulch layer. The landscape fabric’s pores, which normally let air and water through, can clog up with fine silt over time, making it as effective as a sheet of impermeable plastic. Ripping out the non-functioning fabric can be quite the chore.
There isn’t really a good material to use underneath mulch. Some gardeners use cardboard, but it can also absorb water and become hydrophilic. The same is true of newspaper, particularly if there are too many layers. Many of the most recent Extension resources advise just maintaining a sufficient mulch layer and pulling any weeds that manage to poke through.
Personally, I find this difficult to accept because I am well aware that some weeds can easily grow through a layer of mulch. For this reason, you could cover the soil with a thick layer of mulch (over six inches deep) or lay down a few sheets of newsprint to prevent the weeds from sprouting up immediately after soil disturbance. Within a year, the thin layer of newsprint (avoid glossy paper) should decompose, and the gardener will then be responsible for maintaining that mulch layer. It may also be beneficial to use preemergent herbicides to create a mulched bed around a tree. Follow all pesticide label directions.
Another circumstance that frequently occurs to me is a young or old tree that is planted at the ideal height. The root flare is visible. The tree is healthy. The only thing to do is mulch the tree. Unfortunately, it occurs far too frequently for homeowners (and some landscapers) to pile mulch up against the tree trunk. This practice of “volcano mulching” is comparable to “planting the tree too deep.”
These trees’ mounded mulch against the trunk fosters an environment that encourages rot and decay close to the trunk. The suggested mulching technique calls for mulching the root system rather than the tree at a depth of 2 to 4 inches, spreading it as widely as possible, and leaving a 2-inch space between the mulch and the tree trunk.
Last but not least, girdling roots are a frequent problem at the base of tree trunks. Since everything mentioned above encourages the growth of girdling roots, I wasn’t sure if girdling roots merited their own section, but there are a few extras I can include here.
Tree roots should emerge from the trunk, but they frequently form girdling roots in trees that were grown in nurseries. This is because they are grown in plastic containers, and the young root turns and travels in a circle when it comes in contact with the wall of the container. Some people will trim off the sides of the root ball when planting to fix this. Essentially, turning the sphere-shaped root ball into a cube shape.
Another method is root washing, which involves rinsing and cleaning the root ball completely of all soil to reveal any circling roots. These problem roots are then pruned off. Depending on the tree, the top portion may be extremely top-heavy and devoid of soil that would anchor the roots. Staking may be necessary. In 2019, I worked extremely hard to root wash some trees. I used 1×2 boards to secure the root area instead of stakes tied to the trunk, which prevented the trees from falling over while still allowing the trees to flex in the wind and create a strong trunk taper. A newly planted tree may experience considerable stress as a result of root loss. Initial research on this found that although these trees may take longer to establish, over time they tend to develop root systems that enable them to catch up to trees that did not receive any intervention.
And some species, like maple trees, are simply notorious for girdling their roots in urban areas. another justification for choosing a tree other than a maple!
Looking for arborist woodchips? Many utility and tree care companies are searching for locations to dump their woodchips. Give them a call and see if you can get a load; it never hurts. Additionally, many municipal yard waste sites offer residents free woodchips.
It is recommended to mulch young shade trees. I would argue large ones benefit from mulch too. It deters lawnmowers and string trimmers, lessens turfgrass competition, and creates a defined, aesthetically pleasing space around the tree. However, how and what we use as mulch can determine whether a tree is healthy or not.
Another circumstance that frequently occurs to me is a young or old tree that is planted at the ideal height. The root flare is visible. The tree is healthy. The only thing to do is mulch the tree. Unfortunately, it occurs far too frequently for homeowners (and some landscapers) to pile mulch up against the tree trunk. This practice of “volcano mulching” is comparable to “planting the tree too deep.”
Before beginning any kind of diagnosis of the ailing tree, there is one thing I always ask a client for: a picture of the base of the trunk as it protrudes from the ground. Because I tend to find the majority of the issues in large shade trees here, this portion of the tree is crucial.
Personally, I find this difficult to accept because I am well aware that some weeds can easily grow through a layer of mulch. For this reason, you could cover the soil with a thick layer of mulch (over six inches deep) or lay down a few sheets of newsprint to prevent the weeds from sprouting up immediately after soil disturbance. Within a year, the thin layer of newsprint (avoid glossy paper) should decompose, and the gardener will then be responsible for maintaining that mulch layer. It may also be beneficial to use preemergent herbicides to create a mulched bed around a tree. Follow all pesticide label directions.
Because they are usually coarse and don’t pack down like some shredded wood mulches, arborist woodchips are a suggested kind of mulch. These are often readily available in Illinois. When I can’t get my hands on arborist woodchips, I use shredded wood mulch because it’s not a bad substitute. I also love using shredded autumn leaves, and I did so a lot at my previous house.
Do’s and Don’ts of Burying a Tree Trunk
There are a lot of misconceptions surrounding tree planting. You may have heard that trees have to be planted buring the roots and even part of the tree. Making the tree look like a telephone post will make it sturdy and not lean over. Trees need a lot of water especialy during the summer.
But these are some of the reasons why a tree can die. Here are the tips to dispel these misconceptions.
Filling Tree Cavities with Concrete
It is a widespread misconception that filling a tree cavity will increase its structural stability. Tree cavities are best healed by the tree itself.
Trees cannot touch power lines, and power companies are not sympathetic if you want to keep your tree. If you have a tree close to a power line, the utility will compel you to prune or remove it. Consider planting a tree that is small enough to have a projected height that is lower than the height of the power lines if you want to do so.
Contact a local arborist if you don’t know how to prune your tree or don’t have the right tools. This is a very important task that, if done incorrectly, could kill the tree.