JoAnne Skelly: Small tree branches sometimes can be reattached

The winds have been raging, blowing over fences and damaging trees. A big branch broke off my 20-year-old Amur maple. The limb didn’t just break; it twisted and shredded the parent branch to which it had been attached. Another branch on the same tree was cracked, but it didn’t break off the tree.

In some cases of wind damage, branches may only partially tear away from the tree. If it’s noticed right after the damage occurs, small branches can sometimes be reattached. This requires carefully matching up the tissues on the torn branch with the remaining tissues on the trunk or parent branch and then wrapping the wounded area together tightly with a strong breathable material, such as tree wrap, ace bandages or old nylons. After that, it is necessary to stabilize and support the branch to allow the tissues to mend with as little movement as possible. The wrap and supports should stay in place for two to four months.

With the broken branch on my maple, all I could do was to trim as much of the ripped wood as possible in an effort to clean up the wound. Because the wood was shredded, it was not possible to do a proper pruning cut. Because the crack had significantly weakened the second branch, I decided to remove it, too, even though it was still firmly attached.

Whenever possible, repair pruning should follow good pruning practices. Avoid “flush cuts” that cut into the main portion of the trunk or parent branch. Flush cuts damage or remove the branch collar. The branch collar allows a tree to compartmentalize or close off the pruning cut. If the cut can’t seal itself, insects and disease organisms can attack the tree. The best pruning cut is made just outside the branch collar, at a 45- to 60-degree angle to the branch bark ridge.

Whenever removing limbs greater than 1 inch in diameter, use the three-cut method to avoid tearing bark. First, 8 to 12 inches from the trunk cut halfway through the limb from the underside. Second, about 1 inch farther out from the first cut, cut through the limb from the top side. The limb’s weight will cause it to break between the two cuts. Make the third cut just outside the branch collar to get rid of the remaining stub. Do not apply tree paint or wound dressing.

For more detailed information on tree repair or proper pruning, contact me at 775-887-2252 or skellyj@unce.unr.edu.

JoAnne Skelly is the Carson City/Storey County Extension educator for the University of Nevada Cooperative Extension.