Opinion: How to tackle weeds
Waiheke has a reputation of being the second weediest place on the planet after Hawaii and jokingly named ’Weedheke’ by biosecurity officers.
I’m very pleased to see that the Waiheke Local Board has decided to take a well balanced approach to weed control in reserves on the island.
The recent methodology without using herbicides is having a disastrous effect on the health of native bush.
Taking into due regard the concerns of those that feel that herbicides are unacceptable, the board has agreed on an approach that minimises herbicides using manual methods where feasible and carefully targeted methods of application otherwise.
Treescape Environmental is an excellent choice of contractors that has done such excellent work on Rotoroa restoring a very weedy environment using a similar approach.
Modern day Waiheke developed as a community of farmers and more lately holiday bach landowners, who, wanting some quick growing garden plants that stood the rigours of neglect between visits, introduced tough, drought-tolerant nonnative species from South Africa and South America.
These could survive the rigours of summer and lack of care and proved excellent ground cover.
Then through lack of attention they were allowed to grow rampant.
As more and more land has been retired from farming, so bush has re-grown, infested with some of these same weedy species.
As the first ranger at Whakanewha Regional Park and later Biosecurity Officer for Waiheke I was intimately, and often painfully, connected with the results of this first hand.
Some of the park neighbours and others on the island who were firmly against the use of herbicides made a gallant but short term effort to tackle the legion of weeds by hand.
One landowner I remember persevered much longer than most until acknowledging that it was futile. He said, ‘‘you can’t do this by hand, it’s just too much.’’
From that time on a variety of other approaches were tried and adopted.
Sometimes it was simply better, more effective and easier to clear all vegetation and start again, replanting with natives as was done very successfully in many areas of Whakanewha and then minimal use of herbicides was needed to control the regrowth of weeds.
While I was there, this work was carried out diligently and methodically with great results.
Now many years of a combination of sheer persistence and careful use of targeted herbicide use the park is in many areas substantially weed free.
Some weeds are best tackled manually in the main, such as moth plant.
Others, like climbing asparagus for instance, cannot be successfully controlled by hand - unless you are willing to provide the funds, and the labour, to sieve every inch of ground to remove the numerous tubers.
In between these extremes are a wide range of options.
A skilled and careful weed control specialist understands these issues and adapts techniques and methodologies to suit the weeds and circumstances, using manual methods where feasible, followed by targeted herbicide application and sprays where there is no other reasonable option.
Without the ability to use of combination of methodologies, the weed problems on Waiheke are going to be insurmountable.
The option of ‘do nothing’ is not one that any environmentally conscious person would choose. Unattended weed problems do not go away, they simply continue to spread more densely and further.
Thank you again, Waiheke Local Board, for having the wisdom to take a balanced approach.
And for employing skilled contractors to restore Waiheke’s precious reserves.
Andy Spence lives in Onetangi and is a director of Cut ‘n Paste herbicide.
‘‘The option of 'do nothing' is not one that any environmentally conscious person would choose.’’ - Andy Spence.