The Deans family is well known from rugby, but the pioneering Canterbury settlers can also take credit for one of the earliest conservation successes in New Zealand.
For 300,000 years, the shifting gravels of the Waimakariri River triggered an ever-changing forested landscape across the Canterbury Plains. Stands of kahikatea established where ever conditions were right, but were regularly downed by floods, only to re-establish elsewhere.
Joanna Orwin, the author of Riccarton and the Deans Family, says the tall kahikatea trees in Riccarton Bush are the last generation of trees that began life as part of these natural flood cycles.
The oldest trees are about 600 years old and have lived through two cultural periods, Maori and European settlement, as well as widespread fires that swept the Plains.
She says when the Deans brothers, John and William, arrived in 1843, they were drawn to the place because of the bush, in the same way Maori had been before them.
As the last source of timber and shelter, with the Avon running beside them, this was a natural spot on the Plains, which by then was mostly ferns and tussocks after all the fires.
She says the brothers were aware of the importance of the bush, and when the Canterbury settlers arrived, they gave half of the area to them, while holding onto the other half.
“Because it was one of the few sources of timber and firewood on the Plains, the settlers’ half disappeared within a year of the settlement of Christchurch, which made the Deans brothers even more aware of the importance of hanging on to what they had.”
Their philosophy back then was to use only dead wood for firewood, and once the houses had been build, they restricted the use of fencing timber from the forests to fallen trees.
They consciously preserved as much as they could, and when John Deans died in 1854, his dying wish was that what was left should be preserved as much as possible.
His widow, Jane Deans, took care of the bush for decades, but she also planted exotic trees such as oaks to maintain the canopy. But by the 1880s, she had already realised that it was a mistake as the oaks were suppressing the regrowth of native seedlings.
In 1914, the family gifted Riccarton Bush to the city of Christchurch and it was formally protected. Since then, the Riccarton Bush Trust has managed the site, and decades later, the oaks were felled amid controversy, including tree sit-ins.
Joanna Orwin says the bush is now surrounded by a predator-proof fence to help restore its vegetation as close to a natural state as possible, and it has become one of the city’s important green spaces following the Canterbury earthquakes.