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Gardening Answers Knowledgebase

Search Results for: Trees--Wounds and injuries | Search the catalog for: Trees--Wounds and injuries

Plant Answer Line Question

Keywords: Trees--Wounds and injuries, Neighbor law

How can I find out if my Monkey Puzzle tree was poisoned by my neighbors? I found 6 holes drilled into it on their side.


Before assuming the tree has been poisoned, make sure that the holes were not actually caused by woodpeckers or flickers, since this is common behavior among such birds--and less common behavior among neighbors, one would hope!

In order to determine for sure whether your trees have been poisoned, you may wish to consider contacting a certified arborist. For a fee, an arborist will visit your property and make a diagnosis or recommend another plan of action.

For a list of arborists, contact Plant Amnesty, an organization of arborists and vetted gardeners at 206-783-9813 or visit the Pacific Northwest Chapter of the International Society of Arboriculture.

To pursue a legal solution to the problem contact the King County Law Library where County law librarians will be happy to help you with your research.

The book Neighbor Law by Emily Doskow and Lina Guillen (Nolo Press, 2014) is also a useful resource.

Date 2017-04-22
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Plant Answer Line Question

Keywords: Trees--Wounds and injuries, Thuja plicata

I have a mature Western red cedar with an inverted-V gap in the bark, right at ground level. The point of the V is about 2 ft. off the ground; the base of the gap is perhaps 9-10" across. What's the current thinking on protecting this exposed area from diseases and critters? Paint with some sort of goop? Leave it alone? Or something else?


Here is a link to information on managing bark injuries, from Cornell University's Plant Disease Diagnostic Clinic, which includes illustrations. Excerpt:

"When a split occurs on a tree, what should you do? In recent years, quite a bit of research has been done on closure of tree wounds. These investigations have indicated that tree wound paints are of little value in helping a tree to callus over. For this reason, do not paint or try to seal a split with paint or tar. Tracing the bark around the split can be very helpful in aiding wound healing (Fig. 2). With a sharp knife, starting from one end of the split, trace around one side of the wound, about 1/2 to 1 inch back from the split bark. Stop at the other end and do the same procedure on the opposite side of the split. Knives should be sterilized between cuts by dipping them for several minutes in a 1:10 bleach:water solution or a 70% alcohol solution to avoid contaminating the cuts. Carefully remove the bark from inside the traced area. You should now have a bare area resembling the diagram in Fig. 2. Remember to leave this untreated. A tree growing with good vigor usually calluses over quickest. Encourage vigor in the tree with yearly spring fertilizer applications -- and be sure to provide adequate irrigation in hot, dry weather. Bark splits will often close over completely leaving a slight ridge in the trunk where callus tissue has been produced."

The book Practical Tree Management: An Arborist's Handbook by T. Lawrence et al. (Inkata Press, 1993) confirms the method described above. Trim back the bark to healthy tissue around the wound using tools such as a chisel, gouge, hammer, and sharp knife. Wound margins should be rounded, and damaged wood within the wound should be smoothed with a chisel or gouge, but only to the most minimal level (don't go deep).

If in doubt, I would recommend contacting a certified arborist for assistance. You can obtain a referral from Plant Amnesty or the Pacific Northwest chapter of the International Society of Arboriculture.

Date 2018-05-04
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Plant Answer Line Question

Keywords: Trees--Wounds and injuries, Malus domestica

The bark on our apple tree has split, approximately 24" vertically, revealing the wood of the tree underneath. Is there anything we can do to protect it and help it heal itself? If it were a wound, we'd get stitches for it, but we're afraid to make it worse by wrapping the wrong thing around it.


It is possible your tree's bark split open due to weather extremes (frost cracking or sunscald), or uneven growth. Sometimes it is recommended to score the edges of the split with a sharp tool, but I don't recommend it here because of the length of the split on your tree. Cornell University describes the procedure, however.

According to a following discussion on North American Fruit Explorers, it may be possible to leave split bark to heal on its own.

Missouri Botanical Garden offers the following information on cracks and splits in trunks:

"Cracks and splits in tree trunks are fairly common and may occur for various reasons, but are usually not a significant threat to the tree. Typically, there's not much you can do about them once they occur. They do, however, occasionally signal a serious problem that may eventually kill the tree.
"One of the most common reasons for cracks and splits on tree trunks is frost cracking. Frost cracks occur during cold winter weather. The inner and outer wood in a tree's trunk expands and contract at different rates when temperatures change. When winter temperatures plummet below zero, especially after a sunny day when the tree's trunk has been warmed by the sun's rays, the different expansion rates between the inner and outer wood can cause such a strain in the trunk that a crack develops. Frost cracks occur suddenly, can be several feet long, and are often accompanied by a loud, rifle-shot sound. Frost cracks at a point where the trunk was physically injured in the past.
"Maples and sycamores are very prone to frost cracks. Apples, ornamental crabapples, ash, beech, horse chestnut, and tulip trees are also susceptible. Isolated trees are more subject to frost cracks than trees in groups or in forest settings. Trees growing on poorly drained soils are particularly prone to frost cracks.
"Frost cracks often close during summer, only to re-open in succeeding winters. They do not seriously damage trees, although they do provide openings where certain disease organisms may enter the tree, particularly if the tree is in a weakened condition. Frost cracks are difficult to prevent. Wrapping the trunks with tree wrap paper in fall helps, but is inconvenient to do year after year. Apple growers sometimes white-wash the trunks of apple trees to prevent frost cracks and other winter injury problems, but this is unattractive in landscape settings. The best way to prevent frost cracks is to prevent any injuries to the trunk throughout the tree's life. A professional arborist can bolt frost cracks shut with a technique called lip bolting. Most people simply remove loose bark hanging along the edges of the crack. You should not paint frost cracks or other wounds with tree wound dressing. These materials can trap moisture, causing decay in the trunk."

Date 2017-08-08
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May 31 2018 13:14:08