Winter is Oak Care Season

 

Oak Wilt is a tree disease caused by a non-native fungal pathogen which can afflict White and Red Oaks in the Eastern United States. The disease is more severe in Red Oak species, such as the Northern Red Oak and Northern Pin Oak. Red Oaks will die rather quickly from Oak Wilt, while White Oaks tend to contain the spread of the disease to infected branches.

Oak Wilt is prevalent in the southern Wisconsin counties of Wisconsin, but has not yet spread to some northern areas of the state. This article will introduce you to the signs and symptoms of Oak Wilt (Ceratocystis fagacearum), as well as management strategies we offer concerned homeowners.

Symptoms

One of the first symptoms homeowners notice is the "flagging" of branches in your beloved Oak tree. These are branches with dried and dead leaves occurring in the upper canopy of trees in full sun. These symptoms may occur following storm damage in the summer, because breaks in the tree bark make the tree vulnerable to disease. If you notice summer storm damage on an oak tree, calling an arborist immediately is a great pro-active step to avoiding Oak Wilt.

 
Oak tree showing evidence of Oak Wilt.

Oak tree showing evidence of Oak Wilt.

 

Another symptom of Oak Wilt is the brown discoloration of leaves starting from the tip of the leaf and progressing towards the midrib, though this may be irregular. This symptom can be accompanied by uncharacteristic leaf drop. As mentioned earlier, this disease progresses rather quickly in Red Oaks, leading to rapid death, while White Oaks may only show wilting leaves the first year with symptoms progressing more slowly over the next few years.

Signs of Oak Wilt on Red and White Oak leaves.

Signs of Oak Wilt on Red and White Oak leaves.

Symptoms are useful for leading to a disease diagnosis in plants. Symptoms area plants' reaction to a disease, while the signs discussed next are the causation. Be aware that symptoms can be shared across many tree diseases, which is a common cause of misdiagnosis. The best way to determine if a tree has oak wilt is to take a branch sample from the affected portion of the tree and ask an arborist or other tree professional to evaluate.

Signs

The Oak Wilt Fungus can spread through intersections of Oak roots, which can make its spread difficult to control. The fungal mats in the trees' cambium produce volatile compounds that attract the vector for this disease. (A vector is the transmission factor that causes new infections of Oak Wilt in healthy trees by entering wounds.) Two species of sap beetles are the culprits for overland Oak Wilt transmission. Signs of Oak Wilt would be either the fungal pressure pads found under the tree bark or presence of the beetle.

 

Carpophilus sayi (left) and Colopterus truncates (right)

Carpophilus sayi (left) and Colopterus truncates (right)

Management Strategies

Oaks are particularly susceptible to Oak Wilt infection in the spring and summer, while the beetles are infecting fresh wounds. For this reason, you should only prune Oak trees between November (first hard frost is a good measure) and March if possible. Any wounding from storms occurring between the spring or summer months should still be pruned as soon as possible to prevent infection, and should also be treated with a pruning sealant.

If you have an existing Oak infected with Oak Wilt that needs to be removed, you should:

  1. Schedule a removal in the winter months to prevent further spread to neighboring trees.
  2. Some homeowners may also consider trenching around infected trees to prevent root spread of the fungus. This measure is not a guarantee because you do not know for sure if all the root grafts between trees will be severed, but is a good alternative to the fungal treatment.
  3. Another more effective preventative measure is to treat your trees with a systemic injection of propiconazole, a fungicide that can protect high value trees for up to two years. This treatment can slow the infection of White Oaks with less than 30% crown decay symptoms, but is not recommended for infected Red Oak trees.

We want to help protect your Oak trees and maintain the health of our urban canopy. Contact Heartwood if you need help managing or caring for your oaks ,or if you just have a question.

 

How to Fix a Leaning Tree

Every year, we "straighten up" quite a few trees for various reasons. Trees typically start leaning due to a high wind event, sometimes combined with heavy rains and wet soil. A leaning tree isn't necessarily unhealthy (it really depends on the root condition), but they do look funny in the context of a manicured suburban landscape. This learning spruce tree below made a great case study on straightening tipping trees.

This tree took the cake in terms of size for leaning trees straightened by Heartwood in 2016. This guy was 25-30’ tall, and as you can see it was tipping/leaning a lot. The wet weather in spring (which loosens soil and destabilizes roots systems), combined with strong winds later in the year (which levers trees strongly and pulls on their roots), proved too much for many shallow-rooted spruce trees like this one.

 A leaning tree can be saved depending on the severity of the lean and the condition of the tree.  Often if the roots are exposed or the lean is too great, there is little that can be done to save a tree. This customer really wanted to save the tree, so we gave it a shot. As far as we know the tree is still healthy!

The uprighting process is not too complicated, as you can see in the second photo.  We rigged one rope through a pulley, attached one end to the spruce, attached the other to the poplar, and set up a 5:1 mechanical advantage system. The 5-to-1 is the short yellow rope above the drooping orange line.  The mechanical advantage helps create super-human strength to pull the tree up straight, multiplying the force of the person hauling on the line roughly 5 times (though we lose some energy to the friction of the ropes through the pulleys and hardware.

Once straight, we install three poly cables (ropes) to hold the tree in place.  In this case, two cables went to posts pounded into the ground to help provide stability on each side. The other cable was attached to the poplar trunk, which is the main support for the spruce.  

The biggest concern with leaning trees is whether the roots are healthy and strong enough to attempt to straighten the tree. In this case, the roots were still intact and buried. Beyond the roots, the next concern is what to tether the tree to. In this case we had a sturdy tree that provided me confidence that this could be done. If we had to hold this tree up with only three metal posts, we may have reconsidered our options. 

Once the tree is straight expect to leave the cables in for several years at a minimum, especially with a tree of this size. Each tree is unique so there is really no good way to know how long the tree might need support. Over time the cables will just need to be checked for proper tension.  When checking the tension, you can always let out the cable a bit and see what happens; if the tree does not move at all when the cables are loosened, it may have reestablished enough root system to stand straight on its own. I wish there was a more exact science to this but there really is not!

We had many successes righting many "ships" last year, but we also had some failures. In any case, we forge on willing to straighten just about any tree out there if the owner wants to give it a shot.  I mention this because tree straightening is not always successful, but why not try it if it’s a safe option?

Working with the Community to Upcycle Felled Trees

We are always striving to keep as many felled logs in productive use as possible. By "productive use," I mean preventing good wood from becoming firewood or woodchips and instead becoming useful and/or beautiful products that will be treasured for decades or even centuries. Despite our best efforts, we still end up with lots of firewood and woods chips (both free for customers)!

 
Gene Delcourt with one of his beautiful spruce coffins.

Gene Delcourt with one of his beautiful spruce coffins.

 

Gene Delcourt of Humble Crossings located on the east side of Madison is the main destination of all of our spruce logs.  Spruce is probably the most common tree removal we do and that means there are a lot of nice logs in need of a good repurposing. Gene happily takes them all and turns them into beautiful 100% wood caskets, just like in the old days.

I’m guessing Gene has picked up or we have delivered at least 30-40 logs this year for his projects. Gene can be contacted directly for inquiries into his creations at (608) 354-6923.

 
 

Before we found Gene, our spruce logs were destined for the tub grinder at the Madison city disposal center because few artisans or builders are interested in using spruce wood. Gene loves working with spruce because its readily available and usually involves removing a dying tree. The first question Gene asks is “Was it dead?” This basic question tells me Heartwood and Gene are operating with the same interests at heart.

We will continue striving to salvage as many logs as possible. With people like Gene as partners in this effort, I think we can find good homes for the lumber. If you have a need or desire for whole logs, please contact us to see if we might be a good fit.

Please Hold the Salt!

Road salt is very effective at clearing ice from roadways and walks, but plants bear the brunt of the leftovers. Once the salts dissolves, it infiltrates the soil, creating a salty mess.  

In the photo below are two black walnuts situated at the end of a parking lot. You can see the snow piles at the base of each tree and the salt-coated parking lot. The customer called because there have been dead branches falling from the trees. I looked at the trees after all the leaves were off and thought it would be a straightforward canopy cleaning... remove a few dead branches for safety.

Notice how white the parking lot is!

Notice how white the parking lot is!

Once we climbed up into the trees it became clear that salt was slowing killing these trees. Most of the branches in the upper canopy had dead tips. The branch tip is where the most vigorous growth occurs, and they were dying off. The salt build up in the soil was actually preventing the tree from transporting water to the tips of the tree. 

If you do a quick internet search, you will find the many ways that salt harm woody plants.  The biggest reason is salt’s ability to prevent plants from absorbing or taking up water, also known as physiological drought.  Salt spray along roadsides is another common form of salt damage. The spray coats the dormant buds and essentially burns them, killing the buds or slowing their growth.

When using salt on your property:

  • Use salt sparingly and clean up large spills or piles.
  • Mix some sand into your salt to “stretch” the salt out bit more.
  • Avoid piling snow with lots of salt on the root zone of trees and shrubs.
  • Protect valuable plants with physical barriers to keep salt off of foliage and out of root zone.

Resources for preventing salt damage or minimizing it:

•    Plant salt tolerant varieties of trees and shrubs. This is really good!
•    If you have a pile of salt-laden snow at the base of your tree or shrub that you want to protect, you can flush the soil out with water before bud-break once the ground has thawed. Basically you would have to flood the root zone to purge all the built-up salts present.
•    Use only sand or familiarize yourself with an ice scraper. My dad can attest to my extensive use of this tool as a kid, so I could shoot hoops all winter outside.

There is a lot of good info on the web about salt and the damage it can inflict on plants and trees. This is a only a starter to get you thinking about it.  Educate yourself and others on the consequences of salt, so as a community we can keep our canopy as healthy as possible.

Follow the links below for further reading on the impacts of salt on our Dane County our drinking supplies and waterways.

Give Your Autumn Blaze a Hug Up Top

So as proof that we can learn and advance our skills, with great pride I want to show you our newest technique for cabling some autumn blaze maples. Cameron of Lundin Tree Care was not super impressed when I told him about our new technique. “I’ve been doing it that way for a while now.”  Well, I'm glad we caught up!

Anyways, you can see the four sides of the cable that form a basket or loop in the upper 1/3 of the tree. We are moving towards this style because so often the tops of these type of maple are loaded with vertical growing trunks. Putting a basket around all the trunks helps to prevent any of them failing during a storm event. The conventional way would be to install cables between two trunks. Autumn blaze is notorious for many, many trunks (leaders) which means lots of cables going between the many leaders.

Installing the basket around all of the leaders solves this problem and protects the entire center of the tree. It might not be completely visible in the photo, but we did do a pretty extensive train prune on the tree before installing the basket. The last reason that this technique works is because the tree is relatively small at this point. In ten years the tree will be much bigger/taller and require a different system to hold it together.

 

Bare Root Tree Planting versus B&B

This article distills our years of tree planting experience into a short article to illustrate the differences between bare root and "B&B" tree planting techniques. 

Bare Root Planting

Planting a tree in the "bare root" style is very literal. If you look at the below photo, you'll see the tree is all plant: no soil included in the root mass, only roots and the trunk.

Balled and Burlapped Planting (aka "B&B")

The alternative to bare root planting is the a "B&B tree," which stands for balled and burlapped. The roots are enclosed in a ball of soil with a burlap bag and wire basket around the ball.  This is the more conventional approach to planting trees, but requires more digging (typically using heavy equipment) to move the trees due to the shear weight of the soil.  Below is a photo of a red bud tree with the burlap and basket removed for planting.

Now that you can picture the difference between the two options, let's discuss the pros and cons of each. 

 

Pros of Bare Root Planting

  • Can be planted by hand (very light)
  • Less expensive
  • Correct planting depth every time
  • Planted with a larger root mass intact
  • Quicker establishment of tree in relation to B&B

Cons of Bare Root Planting

  • Limit on available species of trees
  • Limit on size to 2” diameter trees
 
 

Pros of B&B Planting

  • No limit on trunk size of tree transplanted
  • No limit on available species of trees

Cons of B&B Planting

  • Heavy, often requiring equipment
  • Can be planted too deep
  • More expensive v. bare root
  • Majority of roots are removed
 

The photos below highlight some of the important advantages and disadvantages of each planting method.

 
This swamp white oak died a year after it was planted 4-5" too deep.

This swamp white oak died a year after it was planted 4-5" too deep.

 

This photo above is the root system from a 3” caliper (trunk) swamp white oak that died the first year after transplant.  Notice the tape around the trunk? That was the planting depth, you can see the root flare (where roots meet the trunk) was around 4 - 5” buried.  Also notice how small the root system is (approximately 16” across) for a tree that large.

Compare the previous root system with the root system of the bare root tree below.  This is a 2” sugar maple that was planted later that day.  This root system is exceptionally wide and is not the norm, but it does show you just how many roots that swamp white oak that died above lost in the transplant process.       

Sugar maple sapling with 6-foot-long roots. 

Sugar maple sapling with 6-foot-long roots. 

The last series of photos show the planting process when a b&b tree is planted too deep at the nursery.  This series features a 5-6’ red bud I planted last spring on a playground.  The first shot is of the root ball exposed and in the hole.  The next one shows the trunk partially excavated to expose the root flare or proper planting height.  The third photo has a 7-8” tall wire cutters in the shot to show you just how deep this tree was, the top of the wire cutters represents the original soil height and the bottom shows the final planting height.

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I don't want to discourage people from buying b&b trees, but I do want to educate people on potential downfalls of getting a b&b tree and just “plopping” it in a hole.  If you are contracting tree planting, make sure that the company knows how to plant trees correctly.  Planting depth will dictate the long-term survivability and vitality of your tree.  

I would like to encourage people to consider bare root trees for their future planting projects. Either way you can’t go wrong planting trees, just make sure it's done correctly so the benefits will outlive us all.

Planting Depth: Give Your Tree the Flare it Needs!

Root Depth Affects Tree Health

Have you ever noticed a tree that looks like a pencil stuck in the ground while walking down the street?  Here in Madison these trees are not hard to find, just try looking around next time you are out walking around.

But how many trees in the forest look like pencils stuck in the ground?  None. They all have formidable root flares, where the trunk gets wide and meets the soil line.  From that soil line to 12 inches down is where you will find most tree roots. The roots stay close to the surface in order to facilitate oxygen exchange essential for the tree’s survival. 

This is how a forest-grown tree looks. Note how the trunk flares to the roots well above the soil line.

This is how a forest-grown tree looks. Note how the trunk flares to the roots well above the soil line.

Now imagine throwing a 6” layer of soil over the top of the forest floor, drastically cutting the oxygen supply to the trees. This is essentially what happens when we plant trees too deeply.  Not only do we cut off most of the root system (to facilitate transport and planting) during the digging, now we stuck the tree in the ground too deep to get the necessary oxygen. Good luck arborlito, it's going to be tough!

The following discussion addresses planting depth and what to look for when you are doing it yourself or reviewing others' work. I have no problem looking over someone’s shoulder when we are talking about the future of our urban canopy.  Please read this and other discussions on tree planting to get a full and comprehensive understanding of how to complete the task correctly.  I’m trying to emphasize the most important step of planting here, planting depth.

How to Determine Proper Root Depth When Planting a Tree

When planting with b&b (balled and burlapped) or container sapling stock, the first step is to locate the root flare (where the trunk get wider, near the bottom). Don’t assume the root flare is just below the soil surface; I have found flares as deep as 8” below the soil line in some balled and burlaped trees! Once you locate the flare, dig your hole accordingly. Please remember not to dig too deep!  If in doubt, err toward making the hole too shallow.  

Carefully place the tree in the hole. We almost always remove the entire basket and burlap material, but this takes practice and care. If you want to remove everything, just make sure not to disturb the root ball, as you don’t want to loosen the soil around the roots. If the root ball is already pretty soft or loose, don’t take the basket off. 

 
NO: The "pencil in the ground" look - a result of planting a tree too deeply.

NO: The "pencil in the ground" look - a result of planting a tree too deeply.

YES: Proper planting depth makes trees look like this in the end.

YES: Proper planting depth makes trees look like this in the end.

 

Now you are ready to skim off the excess soil to expose the root flare.  I like to use tools intended for other purposes here.  My favorite tool is hand pruners for peeling soil away, maybe because I always have one nearby. Be careful not to skim off the bark of the roots; you won’t kill the tree if you do some light damage, but no damage is, of course, ideal. If the soil is really hard and difficult to remove, try adding some water. Spraying SOME water might help loosen the soil a bit... at a minimum you will get really dirty and appear to be working hard!

Now you are ready to backfill the hole, making sure not to cover the flare with any soil or mulch.  Put down a 2-4” layer of mulch around the tree, right up to the root flare. Continuous mulching, year after year, tends to build up around the trunk, so keep the flare clear of soil and mulch as time goes on.

Correct planting depth is crucial for long-term vitality and healthy trees. Planting trees too deeply leads to many issues, such as decreased growth rates, slower establishment after transplant, girdling roots, and ultimately a tree removal bill due to the shortened life span. Give your tree some flare, and your attention will be well rewarded. We think the tree looks better like that anyways!

Autumn Blaze Maples: A Beautiful, Fragile Tree That Needs Regular Care

The Autumn Blaze maple tree is a hybrid species comprised of half red maple and half silver maple. The combination has been popular for 20 years in commercial and residential plantings thanks to the combination of gorgeous fall color and rapid growth - exactly what homeowners are seeking.  In addition, the Autumn Blaze is very hardy and can withstand a wide range of climatic conditions.

The big drawback of the Autumn Blaze maple is its structural weakness. The tree tends to crack easily at branch unions, which leads to broken branches and property damage after even mild storms. To avoid problems with Autumn Blaze maple trees, property owners must invest in regular tree care.

Maintaining autumn blaze maples requires regular pruning every 3 to 5 years.  Regular pruning helps keep the structure of the tree sound and prevent some of the issues discussed/illustrated below. I planted an Autumn Blaze at my parent’s house 15 years ago and I prune it every year! My dad is always amazed at how much wood I remove from the tree on a yearly basis.

The two major maintenance issues for this tree deal with the roots and the canopy.  For a discussion on roots and root zones check out some of our other blogs related to that topic. We will discuss canopy management below.

Canopy Maintenance Prevents Broken Branches

If an Autumn Blaze maple tree has been in your landscape for more than five to tens years without any structural or upper canopy pruning, please contact a certified arborist ASAP because these trees require regular pruning.  I’m not exaggerating here, they really do need regular care in order to stay in your landscape long-term. Unmaintained trees develop weak branch attachments (cracks) prone to failure, which ultimately can mean losing the entire tree.

The lowest branches on this tree have strong, circular, horizontal unions.

Past the first few limbs (at left), this tree's unions are deep, vertically-oriented V's. Notice how every union has a vertical crack extending down from the bottom point of the branch union? This is trouble waiting to happen.

This blog features a 14” diameter Autumn Blaze maple that has been growing for 15+ years (see below photos). Since the upper canopy has never been pruned, all its major branch unions (where they connect to the trunk) have developed significant cracks due to included bark. Included bark is bark wedged between a v-shaped branch union of co-dominant stems. In the photos above, the lower branches have strong open unions, while the upper branches that look like v's have included bark. These are branches are most susceptible to high-wind branch failure, also know as sail effect. So this tree needs some extra TLC in the form of dynamic support cables. The cables provide extra support for the weak v-shaped branch unions that are synonymous with Autumn Blaze maple trees.

Reduction Cuts Reduce Canopy Load

With this particular tree we will reduce (shorten) branches competing with the central trunk in order to encourage the central trunk or leader to assume the dominant position in the tree (see below photos). By reducing competing leaders you minimize the risk of branch failure and redirect energy from those branches by removing live tissue.

Before pruning. Notice there is no clear central trunk.

After pruning. Reduction cuts have significantly decreased leaf load in the entire tree and limited competition for leaders, encouraging the central trunk to become clear and dominant.

After pruning. Reduction cuts have significantly decreased leaf load in the entire tree and limited competition for leaders, encouraging the central trunk to become clear and dominant.

Can you believe this much pruned wood came out of this Autumn Blaze? It's difficult to tell from the before-and-after, but it's a lot of wood!

Dynamic Support Cables

This tree is very consistent in terms of (poor) form; without regular pruning from the time of planting it is almost certain to have structural problems. Because this tree had not been previously pruned, it requires more than just pruning; dynamic support cables will be necessary to provide extra support for the weak unions described above. These support cables are permanent fixtures in the tree. Please read Support Systems for more information on dynamic cabling.

Brent adds two dynamic support cables in this Autumn Blaze maple tree to help prevent the trunks from cracking under leaf and wind stresses.

The dynamic cables are placed in the upper canopy and are not very noticeable from the ground.  They will provide added support for the tree making it more likely to withstand heavy weather events throughout the year.  Now that the tree is pruned and the cables are installed it you can enjoy its ever-expanding shade and wonderful fall color.  

Recycle Your Tree

 

Customers ask often about what they can do with trees they have asked us to remove from their property. If you must take a tree down on your property, you often can make use of the wood by choosing one of a number of recycling options. Consider the following:

Log Salvage

If you are a woodworker, or you have a close friend or family member who is, you won't have to think twice about what to do with a felled tree... you'll turn it into something beautiful, of course! But not everyone has the equipment or wherewithal to cut down, mill, and work large sections of wood into furniture, so we like to promote a local non-profit that can help.

Wisconsin Urban Wood is a Madison-based non-profit that connects property owners with salvageable wood with woodworkers who love recycling urban timber to make furniture or other goods. In this way, you can make sure you keep some of your cherished tree in your home as a chair, desk, table, or other piece of furniture, or allow someone else to have the same. 

The tree pictured below serves as a prime example of a tree destined for a long second life. In the hands of local woodworkers and artisans, this tree will be turned into beautiful furniture and/or custom finishing wood. The branch union (where the trunk splits) can often be used to make interesting desks or other furniture, while the main trunk is often milled for flooring, boards, or other "straight" uses.

Cameron measures a sizable felled white oak tree on Madison's west side. The tree died a natural death and needed to be removed. 

Cameron measures a sizable felled white oak tree on Madison's west side. The tree died a natural death and needed to be removed. 

Firewood

You or someone you know might enjoy using your felled tree as firewood. Firewood.  The one major caveat to keeping firewood is to make sure the firewood does not harbor any contageous diseases that could infect remaining trees in your landscape.  Some common diseases to be careful of are oak wilt and Dutch elm disease.  If you do keep diseased wood, make sure to split all the wood and remove the bark.  In some cases (as with oak wilt and Dutch elm disease) you may need to seal the wood pile for a season so the bugs that carry the fungus die in the wood pile and don't transmit the disease your living trees.  Always make sure to know where your wood is coming from, especially green  firewood (has not been dried or split).

NOTE: Dane County wood is under quarantine due to Emerald Ash Borer, so firewood should not travel more than 10-15 mies, if at all. Please do NOT transport wood from your Dane County home to a vacation home or campground up north, as you may bring EAB along with you!

Woodchips

If you or a neighbor would like woodchips for landscaping, we can leave a pile on your property from the wood we remove.

 

Why is My Tree Sick?

Trees, like people, get sick for many reasons. It is difficult to explain how to diagnose tree diseases, but we will share the first steps you can take toward helping your tree get better.

1. ID YOUR TREE. First, figure out what kind of tree you have. What Tree Is It? can help you identifying your tree. Each species has a handful of diseases or pests they are susceptible to, knowing the species narrows things down quite a bit.

2. OBSERVE YOUR TREE. The best information clients can provide us is collected over a period of time. Have a look up into the canopy and observe the tree over a period of time, taking written notes of changes you see. If you don't have the luxury of long-term observation and need answers now, just make notes of what you see now.

How do the leaves look? Are they burnt on the edges? Do they have spots on them? Are they falling off? What does the bark on the tree look like? Do you see any fungus (this would be mushrooms, or different colored growths on the bark)? Lastly, has there been any changes to the tree's environment in the recent past? Construction, soil compaction, large limb removals, or an injury to the stem are just a small part of large list of things that will affect tree health.

3. GET HELP WITH DIAGNOSIS. If you're unsure whether your tree is sick, or you know it needs help, we are happy to come out and have a look.

Resources

If you want further information on sick trees please go see Dane County's tree disease and insects page. You can also check out Trees Are Good for more guidance.