21 July 2009
Trees – can we afford not to protect them?
Trees. For some they are a great view. For others they block a great view.
With the Local Government and Environment Committee’s report on the Resource Management Simplifying and Streamlining
Amendment Bill due Monday 27 July, the New Zealand Arboricultural Association (NZAA) is emphasising the many benefits of
Lisa Sanderson, NZAA Vice President says often the irreplaceable benefits of trees go unrecognised.
“Urban trees have numerous functions that would be prohibitively costly for the Government and taxpayers to replace if
they were lost from our cities. These range from bringing money into the country by increasing tourism through the good
ol’ clean green New Zealand image, to reducing the amount having to be spent on storm water, silt control and health
care, to name but a few.”
Such benefits are backed up by numerous studies worldwide, including one that demonstrates how trees increase revenue in
business districts. A New York City Council study shows each council owned street tree (excluding trees in parks and on
private property) brings to the city US$5.60 in benefits for every US$1 spent, totalling US$122million in increased
revenue for the city 1. This is a huge profit compared to the costs of processing resource consents – an issue that is
currently being considered by the Local Government and Environment Committee.
Ms Sanderson says trees also provide benefits at individual household and business levels.
“Urban trees can reduce energy bills from excessive air conditioning and heating use by 10-50% 2. Trees also protect
more properties from storm damage than those that are damaged by direct tree failures.”
Ms Sanderson adds: “Trees are life supporting systems, and can increase physical and mental health well being. Trees
provide oxygen, reduce respiratory disorders, shade skin from UV damage, act as air filters in increasingly polluted
urban environments, and provide a pleasing and amenable environment.”
And while many of us think we understand the environmental benefits of trees, it is worthy of note that they provide
stability for river banks and coastal cliffs, and give filtered shade to waterways which is vital for the life of New
Zealand fish and aquatic life.
Ms Sanderson says: “Trees support our birds, skinks, geckos and invertebrates. They assist in holding on to what
remains of our poor New Zealand soils, which is crucial in retaining the country’s reducing natural nutrient resources.
They sequester our carbon and even help us keep our city temperatures and micro-climates controlled in light of climate
All of these irreplaceable benefits are not only paid directly to the owner of the property on which a tree stands, but
are vital economic, health and environmental benefits that should be guaranteed, by way of effective tree protection,
for all Kiwis for the future.