Wellington's original Christmas tree, the rātā, are now in full bloom

Wednesday, 23 December 2020

Wellington's original Christmas trees, the rātā, are in full bloom in Otari-Wilton's bush, a rare sight only possible thanks to more than two decades of possum control. Drone videography by Nick Gee.

Move over pōhutukawa. Masses of Wellington's rātā trees are now in full bloom, towering overhead and resplendent in red, just in time for Christmas.

Those in Otari-Wilton's Bush predate humans in New Zealand; huia would have perched in their branches, and moa walked over their roots.

These are the region’s original Christmas tree, said Wellington City Council environment partnership leader Tim Park.

“It’s quite an unusual year this year. All the rātā trees are flowering. Normally only one or two flower, but this year it’s all on,” he said.

**READ MORE:

Resplendent in red, the northern rātā trees at Otari-Wilton's Bush are in full bloom for Christmas.

* How to grow your own pōhutukawa trees

* Rare white rātā in Lower Hutt, rarer than the kākāpō

* Kākā, kererū and tīeke are three times as likely to be seen in Wellington compared to 2011

Wellington City Council environment partnership leader Tim Park at Otari-Wilton’s Bush, home to huge flowering rātā trees.

The abundant flowers are thanks to the possum eradication efforts from the past 25 years.

Previously, the pests would have made a meal of the trees. Some skeletal branches remained, scars from past possum attacks.

Previously, possums would have made a meal of these trees, but eradication efforts over the past 25 years have made a huge difference.

“Possums find one tree they like, and hammer it,” Park said. “Then the tree responds by growing new shoots, which is exactly what the possums want.”

The tree eventually ran out of energy, unable to produce new growth. If that happened to enough trees, forest collapse would take hold.

Possum traps and later bait stations throughout council reserves had been instrumental in effectively eradicating possums from the Wellington urban area. That’s the reason there are virtually no road-kill possums in Wellington, Park said: there are no possums to run over.

This was an unusual year for other reasons.

Otari-Wilton’s Bush has been a focus of predator-free efforts over the past couple of decades with attempts to rid possums hugely successful.

“Many of our native trees do a thing called mast flowering, it’s when they all flower at once in synchrony,” he said.

“It’s thought to be a strategy to prevent seed predation as there is simply too much around to eat. It’s well studied in our beech trees, and thought to be the result of warmer summer weather, so more frequent masting events are thought to be linked to climate change.”

The mature northern rātā in Otari-Wilton's Bush were hundreds of years old, lucky to escape unscathed from forest clearing which wiped out all but 2 per cent of Wellington’s native forest when settlers began farming.

Rātā were hard to date, Park said. Unlike pine trees, they don’t develop rings in their trunks as they grow.

Northern rātā could grow from the ground, but usually begin life as an epiphyte – a perching plant high in the canopy of a host tree. They wound their way around the host, and eventually put down roots of their own, taking over its spot in the forest.

Despite the similarities, there are many ways to distinguish between a pōhutukawa and a rātā.

Pōhutukawa trees have denser, more prolific flowers, and the leaves are larger and darker green with slightly rolled edges and fine white hairs on the undersides. Northern rātā leaves are glossy on both sides.

Native birds like tūī, bellbird and kākā feed on rātā, and bees, bats, and lizards drink the nectar.

Wellingtonians can visit www.pfw.org.nz/get-involved to help with conservation efforts – from backyard trapping to tree planting.