Tree Health Assessment & Rehabilitation: Caring for the Lungs of Our Urban Centers

CEBU, Philippines - Trees offer life but do we really care? The rate we destroy our forests and the gravity of neglect we afford to trees in our backyards, the roadsides and parks are evidence of our lack of knowledge and appreciation on the countless values of trees.

In recent years, the shade and cool environment that trees offer are non-negotiable, especially for many poor urban dwellers who cannot afford costly air conditioners or even just stroll in malls to escape the sweltering heat during summertime or even unexpectedly during supposedly cold season (the effect of global warming phenomenon!).

But it is a fact that trees offer various important servi-ces and products. Prof. T.M. Das of Calcutta, India even calculated economic value of a 50-year old tree to be as high as Php8,309,750  (based on a conversion factor of 1USD:43Php). Accordingly, this estimate does not include the value of products offered by trees such as fruits, timber and aesthetics. Some may not totally agree with him, but nobody can deny the fact that trees produce precious oxygen that we humans need in order to survive. Thus, trees are aptly called the “lungs of the environment”.

Sadly, just like vicious smokers oblivious, if not neg-lectful, of the consequences of the vice to their lungs, humans are not mindful of their actions to these lungs, most especially in urban areas.

Based on the results of the DENR-ERDS 7 health assessment of trees in selected public parks and roadsides in Region 7, most trees are subjected to stress factors that we humans are to blame for. These include, among others, the practice of nailing or installing something to a tree (may be signboards, posters, lighting fixtures, etc.) or tying it with tie wire or electrical wire. These practices cause deformities on trees or create injury which becomes entry point of decay-causing organisms.

In many cases, improper pruning procedures lead to branch and stem decay while road concreting (or expansion of existing ones) injures root system of roadside-planted trees. If not checked earlier, decays in trees, especially those in the main stem and roots can be very dangerous to humans and properties. In many cases, stem decays are not clearly visible at the surface but may be already large enough at the core. Coupled with unbalanced crown (due also to wrong pruning practices), stem decays could turn trees into a menace… especially during rainy and storm season.

There were instances already in Cebu and Dumaguete where large century old acacia trees accidentally fell, damaging lives and properties.  But these could have been prevented if only we care for our precious trees.

Nowadays, there is an increasing interest in tree planting activities. It is a sad fact, however, that we disregard those trees that are already there — the large, towering, century old trees that could have been mute witnesses to a very important event of our history. Take for instance, those Acacia trees in Plaza Independencia or those along the national highway that stretches from Naga to Carcar.

Undoubtedly, money is spent in planting trees and with the values they have, it is just right to give them the appropriate care. It is our patriotic responsibility to rehabilitate those which are defective or ailing.

Two of the most important tree rehabilitation measures that the DENR has been espousing are corrective pruning and tree surgery. These measures help minimize risk, enhance aesthetic values, restore ecological functions, and lengthen the lifespan of a tree.

Tree surgery involves the processes of excavation and removal of decayed wood tissues, sterilization and application of fungicide to excavated cavity to stop progress of decay, application of sealant, installation of steel bars and mesh wire (depending on the need), filling up of cavity with cement and lastly, careful shaping and application of sealant to the margins of the cavity to allow unhampered growth of the cambium layer.

The DENR-7 through its research arm, the ERDS already started its technology transfer and capacity-building campaign to the local government units of Region 7 as well as concerned private institutions and academes. Series of trainings were conducted in Cebu City and Tagbilaran City in March and August 2012 and in Dumaguete City last May 2013. These initiatives are part of the DENR-ERDS 7 Research and Development Project on Tree Health Assessment and Rehabilitation of Defective Trees in Selected Urban Areas of Region 7 under the supervision of Ecosystems Research and Development Bureau in Los Baños, Laguna.

Initially, the project aims to assess health of trees in roadsides and public parks, determine healing rate (through callous formation) of rehabilitated/treated trees and capacitate concerned LGU staff and managers of public parks/roadside plantations and those concerned private institutions and academes on appropriate urban tree care, maintenance, and application of tree rehabilitation/treatment strategies through hands-on training and on-site coaching.

Tree rehabilitation demonstration sites are located in Cebu City (Plaza Independencia, Jones Avenue and Fuente Osmeña Rotunda), Carcar City (City Plaza and City College), Argao (Argao Nature Park), Tagbilaran City (Carlos P. Garcia Park), and in Duma-guete City (Quezon Park).

The establishment of these demonstration sites were made possible through the cooperation of the concerned city and municipal governments. Especially, in Cebu City, through the active support of Dr. Librado Maca-raya and Mr. Arliegh Gesta of Cebu City Parks and Playground Commission; in Dumaguete City, through its City Administrator, Mr. William Ablong; in Carcar City through Mr. Diomedes Campugan and Mr. Bing Barolo; in Tagbilaran City through For. Samuel V. Racho; and in Argao, Cebu through the then park consultant, Mr. Boscap Jumao-as.

With the project, it is hoped that days are gone when axe and chainsaw are the only solution to a defective and a seemingly risky tree. No less than DENR-7 Regional Executive Director, Dr. Isabelo R. Montejo emphasized the existing environmental laws (P.D. 953 and R.A. 3571) requiring the planting of trees in certain places and penalizing unauthorized cutting thereof.

After all, just like us, a tree is also a living organism. It helps us sustain our existence. It is thus proper for us to give them utmost care.

For more information and technical assistance on tree rehabilitation, contact the DENR-Ecosystems Research and Development Service (ERDS) thru telephone no. 346-2209 or 346-2271 or email [email protected].

Science Research Specialist II, DENR-ERDS 7, Banilad, Mandaue City (FREEMAN)