Practical Tree Surgery 



By J. Franklin Collins, Washington, D. C. 



Tree surgery, or. more [jroperly, tree repair work, is 

 not a mysterious art known only to a favored few who 

 alone are fitted to undertake it. It can Ije undertaken by 

 any careful man who has a good general knowledge of 

 the structure and life history of a tree, its normal manner 

 of covering wounds, and how insects and decav organ- 

 isms cause damage, provided he can handle a gouge and 

 mallet, a saw, and a tar brush and applies in a practical 

 manner his knowledge of the anatomy of a tree, together 

 with a generous admixture of good common sense. For 

 work in the tops of trees he will also need a clear head 

 and ability to climb. Many tree owners and manv per- 

 sons in charge of private estates are well qualified to un- 

 dertake tree surgery if the requisite time is availal)le and 

 they will familiarize themselves with the fundamental 

 principles and operations underlving the work, at least to 

 the e.Ntent presented in this article. 



It is no easy matter to find a place where the well-worn 

 phrase "prevention is better than cure" could be ap])Iied 

 with greater appropriateness than in connection with tree 

 surgery. Ice or wind may break limljs or uproot trees 

 which inju.re others as they fall. Horses commonlv gnaw- 

 away portions of tj^e liark of street trees unprotected by 

 tree guards. Telephone, telegraph, and electric linemen 

 with their climbing spurs and saws are notorious muti- 

 lators of shade trees, especially in towns where the trim- 

 ming of trees is not regulated by law. Poorlv insulated 

 electric wires of high voltage often discharge heavy cur- 

 rents through the trees. Wheel hubs frequently tear'awav 

 large pieces of bark, .\fter a few years, decay may pene- 

 trate into the interior of the tree from any or all of 

 these injured places. This decay may increase from \ear 

 to year until large limbs, or the trunk itself, become 

 so weakened that they are easily broken by violent storms. 

 It requires comparatively little time and expense to clean 

 and paint a fresh injiu-y. It (iften requires much time 

 and expense to treat properly the same injury after it 

 has been neglected for a few vears. 



The most economical and reliable remedy for a decayed 

 area consists in attending to an injury as soon as it is 

 made, perhaps 20 or 30 years before it becomes a menace 

 to the tree. This fact should never he forgotten bv tree 

 owners or persons who are charged with the care of trees. 

 If put into practice, it will insure a profit of man\- hun- 

 dred per cent on the original outla\-. 



In its simplest tyj^e. tree surgery, as it is popularly 

 imderstood at the present tin^e, consists in removing dead 

 or decayed limbs or stubs from a tree and treating the 

 scar with an antiseptic and waterproof covering to pre- 

 vent decay while healing. Another type consists in 

 cutting out the decayed and diseased matter in trees and 

 filling the cavities with cement or other material to facili- 

 tate the normal bealing-over process. This is often 

 referred to as "tree deiitistr\'."' a term which very aptly 

 indicates the character of the work. Filled cavities do not 

 increase the strength of the trunk or limb to the extent 

 that is generally supj-osed. 



The work on dead or diseased branches can be re- 

 garded as comprising but two essential operations : I 1 ) 

 Removing the branches in a manner that will ]irevent in- 

 yry to the surrounding bark and cambium, whicli is the 

 t'-'n and usually watery layer of young tissue located be- 

 t-c:n the bark and wood of all healthy parts of a tree, 

 and (2) sterilizing and waterproofing the scars. 



*From Atuc>-icau Forestry. 



A large limb should never be removed by sawing 

 through from the upper side, as this usually strips the 

 bark and wood below the scar. The proper way is to 

 make the first saw cut on the under side, from six 

 inches to a foot beyond the point where the final cut is 

 to be made. It should reach from one-fourth to one- 

 half through the liml>. A good time to stop cutting is 

 when the saw becon:es pinched in the cut. The second 

 cut is made on the ujipcr side of the limb, an inch or 

 two beyond the first one. This is continued until the 

 limb fails. After the limb has fallen, a third cut is made 

 close to the trunk and in line with its woody surface. 

 When nearl}- sawed through, the stub must be supported 

 until com])letely severed, so as to avoid any possibility 

 of stripping the bark below as it falls. The first and 

 second cuts to prevent stripping may be omitted when 

 small limbs which can be held firmly in place until com- 

 pletely severed are being cut. 



\\ hen the scar is not naturally pointed above and be- 

 low, it is a good practice on most trees to remove a short 

 triangular piece of bark from the upper edge of the scar 

 and another from the lower edge, so as to anticipate its 

 dying back at these points. This makes the scar pointed 

 at both ends, the most favorable shape for healing. It 

 is in^portant that some good shellac be applied with a 

 suitable brush over the edge of the bark, especially the 

 cambium, immediately after the cut is made. If the scar 

 is a large one, it is a good plan to use the knife for one 

 or two minutes and then shellac the freshly cut surfaces, 

 repeating the operation until all the bark around the scar 

 has l)een shellacked. The full Ijenefit of the shellac will 

 not be achieved if many minutes elapse between the 

 cutting and the shellacking, unless the freshly cut sur- 

 faces are visibly moist with sap. 



If necessary, the woody surface of the scar may now 

 be smoothed off vyith a chisel and mallet to conform in 

 general shape with the tree trunk. It is bad practice to 

 leave a stub projecting from a trunk. 



Tlie final operation is to sterilize and waterjiroof the 

 surface of the exposed wood and bark. For this purpose 

 manv preparations have been used. Recent extensive 

 tests by specialists in timber preservation indicate that 

 some of the creosotes stand far ahead of all other tested 

 preparations in their power to destroy and prevent the 

 growth of certain wood-destroying fungi and that 

 ordinary creosote, ahhough it does not head the list, is 

 far better than other preparations except some of the 

 less known and less available creosotes. Furthermore, 

 creosote penetrates the wood better than a \yatery anti- 

 septic. In using commercial creosote, it can be applied 

 with an ordinary paint brush over every part of the ex- 

 posed wood. The entire shellacked and creosoted sur- 

 face must finally be waterproofed liy painting it with 

 heavy coal tar. A single application of a mixture of 

 creosote and coal tar (about one-fourth or one-third creo- 

 sote) .has been quite extensively used with good results. 

 Although one coating of this mixture may at times be 

 sufficient, it is always safer to follow it with a heavy 

 coat of coal tar. 



Permanent waterproofing can be secured only when 

 the treated surfaces are watched from year to >ear and 

 recoated when an\- tendency to crack or peel is observed. 

 This is an important step, which is almost invariably 

 neglected by tree owners and tree surgeons. 



During the last few years there has been a widespread 



