30 Mar 2021

Focus on planting exotic forests key to climate goals - forest owners

8:05 am on 30 March 2021

Planting non-native trees is a better way for the government to tackle climate change than focusing on just native forest regeneration, the New Zealand Forest Owners Association says.

A tramper stands against sequoia redwood trees, growing in their native California.

A tramper stands against sequoia redwood trees, growing in their native California. Photo: 123rf

Their suggestion was one of more than 10,000 submissions to the Climate Change Commission's draft advice on climate policy when consultation closed on Sunday.

Forest Owners Association president Phil Taylor told Morning Report the commission's advice to focus on planting native trees overlooks a more pragmatic approach, and using a mix of natives and exotics (non-native trees) would make the climate goals more achievable.

"I'm not saying [exotics] are better than natives, the issue with natives is they're extremely expensive and challenging to plant and establish. The Forest Owners Association is not against planting native trees, but we think the CCC have over-relied on their ability to help New Zealand and their climate change ambitions.

"The Climate Change Commission has set some very ambitious targets; 300,000 hectares in the next 15 years. We think that's going to be pretty difficult to do with just natives.

"So we think that they should investigate the option to plant long-lived exotic trees as well - say redwood, douglas fir, both of which in their natural environment can grow for 500 to 1000 years."

Native trees establish slowly, and need more work than some exotic alternatives, which means they're more costly, he said.

"They're very susceptible to weed competition, so they grow very slowly. It's not just a case of planting the trees and leaving them, you have to maintain them for a number of years.

"They're very vulnerable to pest attack, like rabbits. And as the climate change effects take impact it's likely we're going to see less rain, particularly on the east coast areas of the North and South Island, so that's going to mean that water or soil moisture is going to be a problem for establishing natives.

"Different types will work and be easier to establish on different sites - so it's a matter of putting the right tree on the right site, this is what this is about."

New Zealand native rain forest.

New Zealand native rain forest. Photo: 123rf

But planting native trees offers wider benefits by supporting native bird, insect, lizard and plant habitats.

"There's plenty of land in New Zealand that is suitable for establishment of all trees, whether they be natives or long-lived exotics, or indeed plantation forests," Taylor said.

"The advice to plant native trees is a good thing, the challenge we have is achieving those very ambitious targets. So don't discount long-lived exotic trees, that's what we're saying - they're not a replacement to natives, they're a complement to natives."

Either way, Taylor said big adaptations would be needed.

"Given the scale they're talking about we're going to have to do things differently, it's going to require innovation, scale is certainly going to be an important issue, and also different changes in technology."

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