Thursday, July 22, 2010

ISA HK/China --- HK Tree News (Missing Trees in TMO Watch List)

国内朋友请使用翻译软件阅读本文 (http://translate.google.com.hk/?hl=en&tab=wT#enzh-CN)。
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Dear Station Members,

The attached news below described how the local Tree Experts have spotted missed trees regarded by them to be hazardous, after the announcement of the Tree Watch List by the Tree Management Office (TMO) a little while ago. Both Tree Experts are renowned Arborists well experienced in field trees in HK. They have a good credibility in public.

Is it so easy to miss out on Hazard Trees during a Tree Inspection? It should not happen to a trained Arborist or it will be Professional Negligence. However to laymen who are only shortly briefed in the subject, it can easily happen. This is especially true for tree defects above-ground on stem & branches, because the majority of visual inspection is conducted on ground. Branch cankers & cracks facing up the sky can not be seen from standing below. It will take a tree climber to get up there to spot the defects. Very experienced Arborist may also spot the irregularities in tree architecture, to send someone up there to tell him below. Alternatively, a tree with full bloom may be at its end of life. It seeds before it dies. The assessor will need to understand detailed Tree Biology to spot it.

Our territory lacks experienced & well trained Tree Assessors. In view of this, anyone available is called upon to carry out Tree Assessment, in the name of promoting public safety. During the Vietnam War, untrained GI's were sent in to fight a jungle warfare that they were not experienced with. The result was a catastrophe. Let's hope this won't happen to the all-out Tree Assessment in HK.

To stop Hazard Trees from building up again, ISA HK/China recommends first each Govt Dept should design & maintain their own trees from cradle to grave. This will provide responsibilities & liabilities. Each Govt should also have their own Arborists to supervise on trees. Tree Design should be endorsed by an Independent Arborist outside the Dept to avoid Conflict of Interest. A similar practice happens with the Environmental Assessment. Why not for trees?

Secondly, public education is very important. TMO should conduct frequent sessions on tree planting to the public & media, preferably weekly in the initial stage. TMO must talk to these people for good or for bad. It should be done face-to-face, not just over the internet. ISA HK/China is interviewed by the media all the time. The media are now good friends of ours & support us.

Also, listen to the complaints from the conservationists & try to resolve them. Meet them & not avoid them. Talk to them with international experience & practices. Reason with them by research. Discuss with them the consequences to retain bad quality trees. Try to move them by heart.

Arborists' job is to select the right trees, install them correctly, maintain them to proper standards, assess their risks & protect them during construction. We produce quality reports internationally (maybe not locally so far) in our language. We are supposed to have good communication skills & basic legal knowledge to work with others. We do good to our society.

The Arborist Profession in HK is gradually moving towards the world standards, & HK will lead the rest of our territory to follow. May the public give us some time & patience to show our good work to them, & may our profession develop in the right direction to serve our society.

best regards,

Sammy Au
Station Manager

"If a tree is not designed, installed, maintained & inspected properly, it is likely to become a liability rather than an asset."

"Trees are good for the community. Trees need care like human beings. Arborists are the Tree Care Professionals."

鬧市病樹 樹木辦名單漏網

在黃大仙上鸷通往行人路斜坡上,有一棵彎向行人路面逾20度的宮粉羊蹄甲(圖右),詹志勇指該樹根部被水泥覆蓋,遂不足以支撐樹身,一旦遇上巨風很易塌下,但這樹並無納入需密切監察的樹木名單上。

記者昨日觀察維園正門的鳳凰木,發現樹根長有白色真菌(圖3),但該樹卻未有被納入需跟進的官方名單內。

(圖3)

發展局樹木管理辦公室上周五公布逾1100棵需重點護養及監察的樹木名單,當中252棵被指健康有問題要跟進。然而,本報與樹木專家走訪各區發現「漏網之樹」,不少位於人流及車流繁忙地點,雖然健康欠佳,例如嚴重傾斜或遭真菌入侵,卻榜上無名。專家擔心樹木辦篩選過程出問題,忽略大量名單以外需跟進護理的樹,不但市民無從監察,塌樹風險仍然存在。

本報昨日曾聯絡樹木辦了解為何有「漏網」,但至截稿前仍未有答覆。

黃大仙路旁彎樹霉爛恐塌

本報上周六隨香港大學地理系講座教授詹志勇,到黃大仙上鸷銀竹里附近的行人路旁山坡觀察樹木,發現位於梯級旁的一棵宮粉羊蹄甲,向行人路彎曲逾20度,再向上生長,根部則被用作鞏固斜坡的水泥覆蓋。詹志勇指該樹樹皮已「霉爛」,因根部被水泥埋覑,難以支撐樹木,樹身遂彎向行人路,「若最終支持不住而塌下,樹身便向行人路滑倒,剛巧有人經過的話便會被撞及」。
不過,本報翻查樹木辦日前公布的護養及監察樹木名單,當中902棵屬古樹名木及石牆樹,只有252棵是當局評估風險後,列為需作改善措施而要繼續監察的樹木,但名單不包括這棵彎向行人路的宮粉羊蹄甲。詹志勇質疑,今次被納入名單的樹只集中於大樹,「肯定漏了很多有可能倒塌、又近人流車流的樹,所以市民不要以為一起監察名單上的樹就等於安全」。

此外,長春社總監蘇國賢留意到,該252棵需跟進樹木中,只有10多棵是鳳凰木,「香港不少鳳凰木都有真菌入侵問題,需要跟進處理,但只有10多棵上榜,實在不成比例」。他指出本港不少鳳凰木均有結構問題,需跟進護理,否則會重演去年中何文田一棵14米高鳳凰木倒塌事件。

維園門口鳳凰木長真菌

蘇國賢指出,九龍塘達之路與瑰麗路交界,以及維園正門噴水池廣場的大屏幕旁邊,各有一棵逾10米高的鳳凰木,兩棵大樹均有真菌問題,但卻未納入發展局的樹木名單之中。本報昨到上址觀察,發現九龍塘的鳳凰木樹根真菌已被清除,維園的鳳凰木則仍可見樹根生長了白色真菌。蘇國賢認為,維園的鳳凰木附近人流極高,即使樹木未有即時倒塌危險,都應該跟進護理。他又質疑,上述健康欠佳、對途人構成威脅的樹木為何不被納入名單,「究竟是它們未夠多人流車流,所以無做詳細評估,還是因為政府認為它們健康無問題?如果因為這樣而無把它們納入名單,便很令人擔心」。

他又指早前塌下傷人的沙田圓州角盾柱木、皇后大道中細葉榕以及日前於東華醫院倒塌的欖仁樹,均無納入名單,認為樹木辦有必要了解箇中原因,確保逐步建立的樹木資料庫具齊全的資料,包括倒塌風險及密切跟進措施,才能真正減少塌樹意外。