When Snow or Ice Bows and Breaks Tree

When Snow or Ice Bows and Breaks Tree

Marianne C. Ophardt
Washington State University Extension
Area Horticulture Specialist

Heavy wet snow, freezing rain and ice can mean bowed and broken tree limbs and trunks.  What causes limb and branch breakage?  Certain types of trees, especially fast growing species, have "brittle" wood that is prone to breakage.  This includes Chinese elm, silver maple, boxelder, and poplar.  Some tree species have narrow branch angles, making them structurally weaker in situations like these.  The `Bradford' cultivar of callery pear is a good example of a tree with a weak structure due to narrow branch angles.

Another reason for structural weakness in a tree is past pruning practices.  Improper pruning practices, such as topping or stub cutting, leads to the development of poorly attached branches.  There is a great tendency for these branches to break off the tree as they grow larger and heavier, especially when stressed by strong winds or a load of snow and ice.

Trees also become structurally weaker when wood rot develops in the trunk and main branches.  Wood rot is the result of fungi, which invade the tree after physical damage occurs... through wounding, bad pruning cuts, and severe temperature damage.  Severe wood rot can develop through repeated wounding and large branches that have been topped.

Some trees broke under the recent heavy snow-loads but some only bent... bending or bowing was common on young deciduous trees, as well as on certain types of evergreens trees and shrubs.  The wood in these plants is more elastic, with wood bending instead of breaking.  In these cases, it was merely a factor of the snow and ice and the branches yielding to the weight.

Now what can be done about the injured trees and shrubs?  Let's deal with the "bent-out-of-shape" plants first.  According to Dr. Ray Maleike, Washington State University Extension Horticulturist Emeritus, "When snow or ice bend branches and entire trees out of shape, the offending snow or ice should be removed immediately and an attempt made to straighten the bent branch or trunk.  If the plant part isn't straightened very soon after the snow has stopped, the plant may remain bent over... permanently."  Collected snow can be removed with a broom.  Sweep upward to lift the snow off.  However, don't disturb the branches if they're heavily weighted and brittle with ice or you have a concern about the structural integrity of your tree.

Maleike suggests trying to physically straighten the plant or branch once you remove the snow.  He notes, "This doesn't always work, but it does occasionally.  If the young tree or shrub has been squashed down to where it extends into traffic areas, it may have to be pruned."

Around our area there a number branches on multi-stemmed, columnar-needled evergreens, like arborvitae, that have been bent out away from the plant.  Maleike indicates that these may be tied back to the main plant with a soft, non-chafing material like cotton clothesline or nylon pantyhose.  The tying materials may have to be left on for 6 months or more.  He notes, "Tying the plants together before the winter starts is a good preventative for this problem."

What can be done for small trees which have bowed over but have not broken or cracked?  These trees can be staked until they can stand on their own again.  Maleike recommends this procedure, "Drive two stakes, about six to eight inches away from the trunk, into firm ground. (Be careful not to severe major roots.)  Then tie the trunk to the stake at the lowest height, which stabilizes the tree in an acceptable upright position.  A nonchafing tying material must be used."

The stakes should not be left on indefinitely.  They should be removed as soon as the tree can stand by itself again.  This should be within the first growing season after the "bowing" occurred.

Trees with broken branches don't need immediate attention.  However, it's advisable to prune off broken branches as soon as the weather and circumstances allow.  Prune damaged branches back to another branch or the main trunk if necessary... don't make flush cuts and don't leave branch stubs.  On large branches this cut should be made to just outside the branch collar.  Be sure to follow recommended tree pruning practices.  When power lines, large limbs, or main branches complicate the matter, contact a trained and certified arborist.

With the breakage of limbs, sometimes bark is torn on the larger limbs or the main trunk.  To help the tree, the torn bark should be carefully trimmed with a sharp knife to make a smooth, rounded edge to the wound.  Cut only the bark and not into the wood.  No wound dressing materials are recommended for bark wounds or pruning wounds.

Avoid Spreading Disease by Pruning

Avoid Spreading Disease by Pruning

Marianne C. Ophardt
Washington State University Extension
Area Horticulture Specialist

What’s your favorite type of pruning tool... a pair of ratchet hand pruners, a lightweight pair of loppers, or a handy folding pruning saw?  Tools like these are standard equipment for gardeners who have a lot of trees and shrubs in their landscape.  They’re needed to prune off ill-placed branches, remove older wood, and eliminate any dead or diseased portions of a plant.  Removal of these infected tissues is very important in preventing the spread of disease.  However, many of us home gardeners may actually be spreading disease if we’re not disinfecting our pruning tools between cuts.

How can pruning tools spread disease?  According to WSU Plant Pathologist, Dr. Warren Copes, if you cut through a section of stem where a pathogen, such as a virus, bacteria, or fungus is present, then the parts of the pathogen may adhere to your pruning tool. When certain diseases are suspected, it’s a good idea to disinfect your pruning tools after every cut.

Copes also points out that not every dead branch is the result of an infection by a disease.  There are also cultural and environmental problems that can lead to dieback.  Let’s look at some common diseases that cause problems in our area and the “protocol” suggested for disease management through pruning and disinfecting the tools we use.

When we have cool, wet springs, a common problem in this area is sycamore anthracnose, also known as sycamore “blight.” True to its name it attacks sycamore trees.  This fungus disease causes cankers or lesions, which eventually girdle a stem and lead to the death of tissues beyond the canker. Over time, repeated infections create sycamores with unsightly crowns.

Where practical, it’s recommended to prune out the cankers caused by the anthracnose fungus.  This improves a tree’s appearance and more importantly removes a source of future infections.  Cuts should be made four inches below any discolored wood.  The disease is spread primarily by wind and rain, not by pruning equipment.  With this disease, you don’t need to disinfect pruning tools after cutting off infected tissue.

One fungus disease that we’ve seen quite a bit of this year is verticillium wilt fungus.  Unlike sycamore anthracnose, verticillium wilt is distributed within a plant at considerable distances from the area of obvious dieback.  It usually enters the plant by way of the root system and moves through the vascular system to plant tissues.  Dieback of branches and limbs is caused by impairment of the root system and the plugging of the vascular system... the system that transports water and nutrients within the tree.  In our region, verticillium wilt is a common problem on maple, ash, sumac, redbud, catalpa, Russian olive, and smoketree. However, there are many other types of trees, shrubs, and garden plants susceptible to verticillium wilt.

While the verticillium wilt fungus can travel throughout a tree, it’s usually not evenly distributed in the plant.  Copes points out, “Since the pathogen isn’t evenly distributed, it’s difficult to identify where the pathogen would be located and also why the fungus is not always spread on pruning tools.”  Dead portions of trees infected with verticillium should be pruned out, but we must keep in mind that this doesn’t remove the pathogen which is located in the roots.  Pruning tools used on trees that have been diagnosed with verticillium wilt or are suspected to have it, should be disinfected between trees and when you are done pruning.

Some “blights” or diseases are caused by a bacterium rather than a fungus.  The most common one that can cause problems in local landscapes is fireblight,  Erwinia amylovora.  Fireblight attacks many members of the rose family including apple, flowering crabapple, pear, pyracantha, hawthorn, cotoneaster, quince, and mountain ash.

Symptoms of a fireblight infection usually start in the spring with infected flowers appearing water soaked.  The flowers may turn brown to black and fail to fall from the tree or shrub.  The bacteria moves down the infected blossom into the twigs, resulting in the sudden death of other flowers and fruits on the same twig.  Often, the twigs will develop a hooked tip or"shepherd’s crook."  Twigs and leaves look almost black, as if scorched by fire.  As the bacteria moves down a twig into a branch, the tissues darken and die. If the outer bark is cut or peeled away, the inner tissues will appear red and water‑soaked.

Fireblight infections commonly occur in the spring when bacterial strands from dead infected tissues are splashed to flowers by rainfall or irrigation water.  The bacteria may also be spread to the flowers by insects that have visited infected plants.  Fireblight often enters a plant through natural openings in the floral parts.

Infection is favored by wet weather and temperatures between 65 and 86 degrees Fahrenheit.  Because of the relatively low rainfall conditions in this region, fireblight is not often a problem in home landscapes.  However, in some years the spring moisture and temperature conditions are just right.  This past spring’s weather provided perfect conditions for fireblight infections in a number of home landscapes.

Once an infection is noted in a plant, it’s important to prune it out immediately.  Pruning cuts should be made at least 12 inches below any discolored wood.  This is because discoloration is a chemical response by the infected plant.  It takes a while before the discoloration forms in infected wood. 

This rule of pruning at least 12 inches below discolored wood can cause a dilemma.  Copes notes that, “Sometimes, a blighted twig or spur may be less than 12 inches away from a larger limb and such removal would disfigure the tree.  In this case, there is no easy answer. Removing the scaffold limb may be necessary.”  If you don’t remove the limb, you should monitor the tree to see if the disease is still present.  While 12 inches is the rule, the disease doesn’t always follow the rules.  It may be present further down, especially if there is a length of time from the first appearance of symptoms and the removal of infected wood.

Pathologists have not been able to confirm that contaminated pruning tools actually spread fireblight from one plant to another.  However, the accepted practice when pruning off fireblight infected wood is to disinfect pruning tools after each cut.

Now we’ve talked about when you should disinfect your pruning tools, but just how should the tools be disinfected?  Plant professionals use a variety of materials to disinfect their pruning tools including commercial horticulture products and also other chemicals.  An article on disinfecting horticultural tools is available from University of Florida IFAS Extension at:  http://edis.ifas.ufl.edu/ep380t.

Be aware that some disinfecting chemicals are corrosive.  Make sure to wash the chemical off after the final disinfecting, allow the equipment to dry thoroughly, and then coat the metal parts with light oil or a silicone based spray.  If viruses are the suspected disease, clean your tools by washing them with detergent to physically remove the virus and inactivate virus that may remain on the blades.

Painting Tree Wounds?

Painting Tree Wounds?

Marianne C. Ophardt
Washington State University Extension
Area Horticulture Specialist

Should pruning cuts and other tree wounds be covered with some kind of paint? No! Wound dressing or pruning paints are not recommended.  Research has shown that they don't prevent wood decay behind the pruning cut and may even increase the amount of wood rot by keeping the environment moist and dark.  It's better to keep the wound open to air and light.  Sometimes pruning paints are applied for cosmetic purposes.  When this is done, they should only be applied in a thin coat.

Don't Top Trees

Don't Top Trees

Marianne C. Ophardt
Washington State University Cooperative Extension
Area Extension Agent

Topping has frustrated people who care about trees for overa century. John Davey, noted tree care expert, wrote in his book The Tree Doctor, published in 1907, that topping was “the work of ignorant tree men” and that “Nature does not form those beautiful and health-giving tops of shade trees to be cut to pieces to furnish ‘beer money’ for a lot of tree fools.” He referred to those people topping trees as “ignorant and nefarious frauds.”  Davey must called it pretty much the way it was back in 1907 and that’s the way it still is today.

Topping of trees isn’t just a regional phenomenon, it happens all over the country. Even in1907 Davey was railing against the topping practices of trees that practically denuded Philadelphia and other eastern cities.  Just why is topping so wrong?  The list of reasons is long:

1. Topping starves a tree by reducing the amount of leaf surface and thereby reducing the tree’s ability to manufacture food for root growth, tree health, and tree vigor.
2. Topping leaves stub cut ends of limbs open to attack by fungi and insects. Decay fungi can eventually create a structurally weak and hazardous tree. Topping increases an owner’s liability by creating a potentially hazardous tree.
3. Topping shocks a tree by suddenly exposing shaded limbs to full sun, resulting in scalding and damage to the bark and tissues beneath the bark.
4. Topping leads to a profusion of weakly attached sprouts the become dangerous as they grow larger and heavier with time.
5. Topping leads to increased expenses from repeated follow-up pruning and the cost of eventual tree removal. Topping can also lead to lower property resale values.
6. Topping disfigures a tree and robs the landscape of its natural beauty, form, and character.

Why do people top trees? That’s a question asked by many people care about trees.  In 1997, James R. Fazio and Edwin Krumpe received a grant to study why tree owners allowed their trees to be topped. In the study they went to owners of topped trees and asked them questions in a systematic way to find out the reasons that they topped their trees. They did this study in eastern Washington and northern Idaho.

The results of this study were published in Volume 8, Number 5 of the Arborist News, a publication of the International Society of Arborists in an article written by the same James Fazio, a professor in the Department of Resource Recreation and Tourism at the University of Idaho. Here is what Fazio and Krumpe found:

Who Tops Their Trees? People who topped trees tended to be the older segment of the population, not highly educated, and in the lower economic levels. Most of those approving the topping owned their own homes. One interesting finding was that a large amount of the topping (26 per cent) occurred relatively soon after the property was purchased.

Who Does the Topping? While many blame commercial tree pruners for topping trees, it appears that only about half of the topping is performed by commercial operators. About 43 per cent of the time either the owners, their relatives, or neighbors do the topping. 

Why Do they Top? Fazio confirmed what many of us had suspected, that “fear is the primary motivation for topping. Fifty-seven per cent of the residents worried that their tree was too high.  The safety of their house was the main concern.” Fazio and Krumpe also found that 24 per centtopped their trees because of concerns about storm damage, six per cent because they thought it was something you were supposed to do, and then there were a variety of other reasons. Only two of the 83 people surveyed preferred the appearance of topped trees.

At the conclusion of the article, Fazio offered his opinions on what can be done to put and end to topping.

1. "Tree care companies are part of the problem and a key to the solution.” He points out that in every area it tends to be certain companies that perform the majority of topping. Fazio feels that short of establishing tree pruning ordinances, peer pressure may be the only way to stop companies and individuals who top trees.
2. Legitimate arborists should make a point of advertising their affiliation with the International Society of Arborists, along with establishing and advertising “ a no topping” policy statement.
3. Encourage communities of all sizes to have licensing requirements for commercial tree work. “The basis for this license need not be onerous, simply requiring a publicly stated business address and showing proof of workers compensation and liability insurance would go a long way to protect consumers.” It’s interesting to note that the study also included a survey of commercial operators. In trying to reach some of those listed in the phone book, a number of companies did not list a business address and refused to provide it when contacted. Would you want to hire a company that wouldn’t tell you where they were located?
4. Fazio strongly feels that efforts to educate the public against topping trees should continue. While many of the arborists who responded to the survey felt that topping was declining, it’s still a common practice, especially in rural areas. A number of the companies surveyed still offer topping as one of their services. 

Fazio encourages everyone who cares about trees to wage a personal campaign against topping trees. There is plenty of research that indicates why topping is not good for the health of a tree and why topping is an economic disadvantage in the long run. However, we need to understand the needs of a tree owner. Educational efforts should not only include information about the “evils of topping,” but should also inform tree owners about how to reduce the size of their tree with better methods of pruning.  Fazio has fought his own campaign against topping. He is the editor of the Tree City USA Bulletin “Don’ Top Trees”published by the National Arbor Day Foundation.  It’s Fazio’s hope that by 2007, the centennial of Davey’s Tree Doctor, “we can look back on topping as a thing of the past.”

Lawnmower Blight

Lawnmower Blight

Marianne C. Ophardt
Washington State University Cooperative Extension
Area Extension Agent  

Watch out for "mower and line trimmer blight" damage to your trees.  This dastardly disease is the result of tissue damage to the trunks of trees from careless mowing techniques and overenthusiastic weed whacking.  The bark of young trees is especially vulnerable to attack because its thin and tender, but older trees with thin, smooth bark are also susceptible.

Lawnmower blight damages the cambium tissue layer that lies right underneath the bark.  It's only a few cells thick.  The cambium is important because it produces the cells, which develop into the conductive tissue in the trunk.  Damage to the cambium results in decreased flow of water and nutrients upward and sugars downward in a tree.  A tree is "girdled" if damage occurs to the tree all the way around the trunk.  Eventual death is the result of girdling.

Too often we carefully plant and tend our trees, but fail to protect them from "lawnmower blight."  Once a tree experiences this type of damage to its trunk, there isn't much you can do.  Cambium tissue cannot be replaced... it doesn’t regenerate and the tree can't heal itself.  The best control is prevention!

The very best way to prevent damage to the trees is to eliminate grass and weeds growing close to the trunk.  Create at least a 12-inch “weed-free-zone” around the trunk of the tree.  This eliminates the need to mow and potentially damage the tree.  (If you use glyphosate or Roundup to eliminate weeds around the trunk of your tree, be sure to keep the chemical off the bark.  Young bark can absorb the chemical and result in damage.)  Edge the “weed-free-zone” with vinyl edging, bricks, or cedar bender board.  Mulch the area with bark or compost.

Keeping the “zone” weed and grass free isn't just aesthetically pleasing; it's also good for your tree. Research has shown that allowing grass to grow over a young tree's root zone will stunt the tree's growth.  This happens because the grass is a good competitor for water and nutrients.  Another reason is that grass exudes chemicals that retard root growth. 

If maintaining a “zone” around the trunk of your trees just isn't going to work, you can cage your trees with wire fencing or heavy plastic netting that is about 12 inches high.  However, you should have at least a three-inch, weed-free-zone right at the trunk base and keep the caging material from direct contact with the trunk.  This three-inch zone is important because otherwise the grass and weeds will grow up inside the cage resulting in an overgrown, unkempt mess.

Some folks use 6-to12-inch long pieces of large, plastic irrigation pipe to protect the trunk of their trees.  They slit the pipe on one side and then they pry it open to slip it over the trunk.  While this might not be the most attractive way to protect the tree, it does the trick of preventing mower blight.

Espalier – Two-Dimensional Pruning for Trees and Shrubs

Espalier – Two-Dimensional Pruning for Trees and Shrubs

Marianne C. Ophardt
Washington State University Extension
Area Horticulture Specialist

Trees and shrubs are part of our three dimensional world.  It takes an adventuresome gardener to turn a three dimensional plant into one with only two dimensions.  Espalier is the art of pruning that involves controlling tree and shrub growth in a single plane... with the support of a building wall, fence, or trellis.  This type of pruning is an ancient art that dates back to Roman times and was later refined by medieval Europeans to save space in the walled gardens around castles, cathedrals, and monasteries.  They were able to reduce the space needed to grow fruit by keeping the growth relatively flat against garden walls... leaving open space for other garden crops. 

Espaliering also proved useful in cooler climates with shorter growing seasons.  By espaliering fruit trees against south and west facing walls, early gardeners found that they could take advantage of the extra heat in these situations, producing fruit in areas where their climate was usually a little too short or too cool to produce fruit.  These south and west facing sites warmed up earlier in the spring and stayed warmer later in the season.

Another advantage to using espalier techniques with fruit trees was the effect espaliering had on the trees.  Espaliered fruit trees usually come into bearing at an earlier age and are generally more productive with deeper fruit color.  This is because of branch angles and the increased light penetration to leaf surfaces that result from the single plane.

The technique of espalier pruning is practiced by some commercial orchardists today because of the early bearing and productiveness of espaliered trees.  Home gardeners and landscapers often practice espalier pruning for its decorative potential.  Using espalier techniques, gardeners can create screens that don’t take up much room and have a softer look than fences or brick walls.  Espaliered plants can also provide decoration for large, monotonous windowless building walls.

Gardeners should take note that espaliering is a technique that takes time and some expense.  You must select the right type of plants and the right site along with making sure you have adequate support for the plant.  Espaliering a tree or shrub involves pruning and training over time to develop and maintain the framework.

Let’s first chat about what types of plants lend themselves well to the art of espalier. Typically you want plants that have long, flexible branches.  Plants with short or stiff branches are hard to train.  You should also consider the mature height of the tree or shrub.  A tree or shrub, whose mature height is much greater than the wall, fence, or structure you plan to train it too, will be unsuitable.  Favored shrubs for espalier include cotoneaster, forsythia, holly, Pfitzer juniper, Kousa dogwood, pyracantha, winged euonymus, flowering quince, star magnolia, and viburnum. Favored trees for espalier include apple, crabapple, and pear.  Fruit trees that bear their fruit on long-lived spurs are the easiest to espalier.  Fruit varieties that have predominantly spur-type growth, such as Red Delicious, Golden Delicious, and Braeburn apple cultivars along with Bartlett pears, work the best.

In selecting a plant, pick a young, vigorous tree or shrub that has a few well-balanced limbs off the main trunk.  Wait until after the plant becomes well established before you perform the extensive pruning needed to start your espalier framework.  In some nurseries you might be able to find plants that already have some initial espalier training. This will make getting started easier.

When planting your tree, be sure to plant it properly to help insure a tree with a healthy root system.  If you’re planting your tree or shrub against a solid wall, the plant should be situated about six to ten inches away from the wall to allow for air circulation behind the plant.

You will need to provide a sturdy support on which to develop your plant’s framework.  This can be done by stringing heavy wire of at least 12 to15 gauge from eye bolts on the fence or wall.  You can also develop your espalier on a free standing trellis.  Just be sure that the trellis is sturdy enough to support the weight of both branches and potential fruit.  When making a trellis for fruit trees, use 4x4 pressure treated posts, sinking the posts two feet into the soil.  Set the posts about ten feet apart, securing the end posts with stakes and guy wires.  With fruit trees you’ll probably want two to three levels of wire with the bottom wire situated about 18 inches from the ground. 

Designing your espalier is the fun part. A well designed and trained espalier is a real work of art.  If you’re doing your first espalier, you should probably start with a simple design. Some of the most common designs are fan-shaped, T-shaped, palmate, pinnate, chevron or V-shaped.  More difficult designs are cordon, basket weave, and candelabra.  Check pruning books in your local library for diagrams of these designs.  With many of these designs, you’ll need to pattern your wire supports accordingly.  If you want something less formal, an asymmetrical informal espalier can be created by allowing the plant to grow and dictate the design.  Training in this case only consists of keeping growth in one plane.

After your tree or shrub is planted and you have its supports in place, you’ll begin its training.  Spread the main branches onto the supports and tie them in place. You need to be careful not to crack or break branches when you bend them into the wanted position.  New growth early in the summer will be more flexible than older branches.

When tying down the branches, use soft string, strips of rags, rubber grafting bands, plant ties, or raffia.  Avoid using wire that can cut into the bark.  Tie the branches to the supports loosely, leaving some extra room for the branch to grow.  Check the ties every three or four months to be sure they aren’t restricting or damaging the branches.  Replace the tie if its hampering growth. 

Branches that aren’t part of the design should be pruned off the spring after planting. Shape the plant every month or so, removing branches or twigs that aren’t in the correct plane of growth.  Training of simple designs may take only two or three years to develop, but more intricate designs will take longer to achieve.

Espalier is a fun way to relieve the monotony of a blank wall or fence. Anyone who has the heart and patience of a gardener as well as the soul of an artist should give it a try. If you’re successful, you’ll have an interesting and attractive landscape accent... if not, you’ll have a really strange and ugly landscape blemish. 

Garden Note: In our region, gardeners should avoid espaliering on south and west facing walls.  Our intense summer sun and heat will be more than most types of plants can endure, plus plants in these types of exposure are more prone to winter injury. Northern exposures may not provide adequate light for flowering and fruiting trees and shrubs. East facing walls are probably the best bet.

Is My Tree Hazardous?

Is My Tree Hazardous?

Marianne C. Ophardt
Washington State University Cooperative Extension
Area Extension Agent

How do you know when large older trees have become a hazard and should be removed?

There are symptoms that can tip you offthat your tree is a liability that could fall, injuring people or damaging property. Any one or combination of the following symptoms could indicate that your tree is in trouble

Large branches or major limbs are dead.

Large branches and/or the trunk has obvious rotten wood or hollow cavities.

Mushrooms are present at the base of the tree.

Large branches have fallen from the tree and/or there are broken branches hanging in the tree.

The trunk has developed a strong lean.

Large roots have been severed or damaged by construction, such as root excavation, sidewalk repair, or trench digging for utilities.

The soil level over the roots and/or at the base of the trunk has been significantly raised or lowered more than two inches.

Root function has been impaired by installation of pavement or building foundations over the root zone.

The tree has been topped or severely pruned in the past.

Decay and rot is present in old wounds.

Two or more main branches arise from the same point on the tree

If you suspect that you may be at risk from your tree, it would be wise to consult a certified arborist who has had training in hazard tree assessment.  The arborist can analyze your tree’s situation and recommend the best course of action.  This may include removal of the tree, pruning the tree, cabling and bracing the tree, or removal of possible targets should the tree fail.

Whose Tree is it Anyhow?

Whose Tree is it Anyhow?

Marianne C. Ophardt
Washington State University Extension
Area Horticulture Specialist

What would Robert Frost have said about the controversies some neighbors have with trees that border their properties?  After all, he addressed the problems of neighbors putting up fences in his poem, “The Mending Wall.”  The truth is that some folks just don’t get along.  Some people reasonably take exception to leaves from a tree they don’t own blowing into their yard or dropping into their pool, especially if there is a large volume of leaves that they must clean up and dispose of in some manner.  Controversies arise over roots growing into yards and gardens from an adjoining tree, or sometimes the tree gets large enough that it actually grows over the lot line even if it started out on one side of the lot line.  Who’s responsible for a tree planted on the lot line?  This question can cause quite a bit of acrimony. 

There are also increasing numbers of controversies over trees which block panoramic views, especially in Western Washington where housing has become increasingly dense and people pay premium prices for select view lots.  Imagine having paid that extra money for your view and then your neighbor plants a tree and it grows up and blocks your view.  There are stories about people hiring arborists and having them come and cut off the tops of offending trees while the owners are away.  Of course, you can imagine that this causes more than a mild argument.  Arborists are finding that they have to be very careful in finding out about who actually owns the tree they are being asked to prune.

It used to be thought that you could do just about anything you wanted to any part of a tree that encroached upon your property... whether it was limbs overhanging your side of the fence or roots causing havoc on your side of the lot line.  However, current conventional legal wisdom seems to protect trees from wanton acts by not-so-neighborly neighbors.  The following was written for the Washington State Department of Natural Resources “Tree Link” newsletter by Mark C. McPherson, of Hillis Clark Martin, & Peterson, P.S. and appears here with permission.

1.  Trees Have a Dollar Value That Can Be Appraised

We all know that trees are pleasant to have around, and that they reduce pollution, add oxygen to the atmosphere, buffer light and noise, and provide welcome shade in hot weather.  You may not be aware that there is a detailed appraisal formula that yields dollar figures for trees.  The International Society of Arboriculture developed an appraisal method that takes into account a tree's condition, location, species, and other factors to produce a dollar value.

The value may surprise you.  In a recent case handled by our law firm in Island County, nine medium-sized alder trees were appraised at almost $4,000.  Mature hardwoods such as oak and maple can be worth in excess of $5,000 apiece.

2.  Washington Law Allows Treble Damages For Willful Tree Cutting

Washington State in general does not allow punitive damages, but there is an exception for willful tree cutting on someone else's property.  The courts have awarded treble damages in cases where tree cutters have failed to make a diligent effort to ascertain the property line.  Anyone contemplating tree cutting should be sure to determine their property line before taking down any trees.  Anyone whose trees are cut should be aware that the damages may be far more than they imagined.

3.  Trees on Boundaries Are Jointly Owned

Suppose you plant a tree on your property, and over time the tree grows into the property line between you and your neighbor?  Washington law deems that tree to be jointly owned by you and your neighbor.  You cannot cut that tree down without getting permission from your neighbor.  Conversely, your neighbor cannot cut down trees on the property line without your permission.  An increasingly common situation involved branches or roots that extend from one property onto another property.  Washington law provides that these can be trimmed back to the property line.  However, recent legal decisions in California and British Columbia have held that a property owner cannot unreasonably damage the health of a tree by pruning back to the property line.  The law is becoming increasingly protective of trees, particularly in urban areas.  Property owners who damage a tree that appears not to be causing them any harm may have to pay for the damage.

4.  Subdivision Covenants Often Pit Tree Owners Against Those Who Want To Preserve Views

As property values go up, the value of views increases.  This has caused some property owners in certain subdivisions to sue to remove trees under restrictive covenants.  Covenants often contain provisions that are protective of views.  Even if covenants do not contain a specific view covenant, they may prohibit "noxious" or "undesirable" uses, which some subdivisions have interpreted to include view-blocking trees.  These disputes usually depend on the unique facts in each situation, but property owners who are protecting their views have turned to covenants to force neighbors to prune or remove trees.

The increasing value of views has also led some subdivisions to undertake "view zoning."  View zoning attempts to plan for specific vegetation in specific areas.  Large trees may be allowed in certain areas but prohibited in designated view corridors.  This preserves the visual and ecological appeal of graceful mature trees while limiting the haphazard impact on views.

5.  You May Be Responsible For Hazardous Trees on Your Property

Are you liable if a tree on your property falls and injures someone?  This depends on whether you knew or should have known that the tree posed a hazard.  If the injury was due only to an act of God, such as a lightening bolt striking a safe, healthy tree, you will probably not be liable.  But if your tree was diseased or had dead branches, a court may find that you should have known that the tree was hazardous.  This is particularly the case in urban areas where the risk of injury is greater than rural areas.

Why Prune Our Trees?

Why Prune Our Trees?

Marianne C. Ophardt
Washington State University Cooperative Extension
Area Extension Agent

If someone knocks on your door and tells you you're trees needs pruning, beware!  This person may be a qualified arborist looking for work or they simply may be a chainsaw owner looking for some good firewood.  First let's examine the reasons why a tree might need pruning.

Dead limbs or branches with a core of decayed wood are hazardous. They should be removed whenever they become evident.  Also, broken limbs and branches should be properly pruned as soon as possible after the damage has occurred.

Limbs and branches that interfere with utility wires, gutters, roofs, and chimneys should be removed.  Branches that create a safety hazard by obstructing a view of the street or sidewalk should be removed using proper pruning techniques.  Branches that intersect and rub should be pruned to eliminate the problem.

Tree pruning is sometimes employed to lessen crown density in order to reduce wind resistance, to shape the tree, or to allow for greater light penetration. Beware if someone says your tree needs pruning because it's "too big."  Keep in mind that healthy trees with adequate root systems seldom "NEED" pruning just because they are big.  That just isn't true. 

In some cases, tree removal may be a better option than pruning.  Trees warrant removal if they are obviously dead or dying.  Trees definitely should be removed if they pose a serious hazard because of internal decay or the destruction of a large portion of their anchoring roots.  If pruning can't remedy the situation, trees growing too close to a building or crowding other trees should be removed.

Good landscaping can add 15 to 20 per cent to the value of your home.  Healthy, attractive trees are an asset to your landscape's design.  Unhealthy, poorly pruned trees are a liability.  When you hire someone to prune your tree or to help you decide on removal, you should look for a qualified, trained certified arborist, not just anyone who knocks on your door.