Replanting Options For One Tree Hill
Auckland City is currently evaluating options for replacing the Monterey pine on the summit of One Tree Hill, which was felled last October.
A variety of species, tree size and planting options are being considered before a proposal is finalised which will form the basis of a resource consent application. An application is required because of the site's heritage status.
A number of factors will influence the final choice including the physical constraints of the site, public preference and guiding documents such as the Maungakiekie/One Tree Hill Domain Management Plan, which stipulates that the tree must be replaced by another living tree.
The site is a difficult one on which to establish a new tree. Several previous attempts to plant trees on the summit have failed as a result of the dry soil conditions and exposure to high winds.
Four species - totara, pine, puriri and pohutukawa - have been identified as being physically suited to the conditions and have been associated with the summit of One Tree Hill at some point in history.
Of these, the only non-native is the pine which, while very hardy and suitable, has a shorter lifespan than other species.
The puriri would probably find it difficult to adapt to the site and would, therefore, probably not attain great size or be long-lived.
The totara, with its long association with One Tree Hill, has strong support as a replacement. As a native, it is adaptable and hardy, and should tolerate the site conditions at the summit, growing large and living a long time. However, it is slow growing and would need shelter in its early years to survive.
Pohutukawa, also has strong support from a cultural and ecological perspective and is probably the most adaptable and tolerant species for the site conditions. It has the most likely chance of survival and would develop more quickly into a long-lived and fine specimen tree.
Site access and topography limitations mean that it will not be possible to transplant a tree larger than seven metres in height and five tonnes in weight without causing significant damage to the site's archaeological features.
The larger the tree, the more difficult it will be to successfully establish on the site because of water constraints and wind. A smaller tree's survival chances are considered to be greater and it would have the best long-term growth and development prospects.
Three planting design options are being considered – a single small tree, a single, semi-mature transplant and a multiple planting of small trees.
The planting of many small trees, which would be progressively thinned-out until a single tree remained, would allow more than one species to be planted, resulting in a better rate of establishment and faster growth.
Aucklanders are now being invited to state their preferred options and should write to Councillor Bill Christian, Auckland City Council, Private Bag 92516, Wellesley Street, Auckland or fax comments to 373 6213 before the end of January.
These will be taken into consideration when the planting proposal is prepared next month, prior to being debated by the Parks and Recreation Committee on 23 February.
The recommendation approved by the committee will then be discussed by full council at its meeting on 8 March.