Guy Trafford takes a look at what to do with forestry slash, including a Fiji example and a possible role for the Climate Emergency Response Fund

Most people, especially on the East Coast and Tairawhiti Gisborne have welcomed the new regulations regarding the control and removal of slash in the forestry sector. The new rules come into force November this year.

What appears to be missing is what happens to all the new and existing slash.

According to a Gisborne District Council (GDC) report, around 500,000 tonnes of slash/pruning’s are produced per year on the East Coast alone. A quick look at the farm forestry site and I found that between 8% -10% of harvested timber is waste. Also, there is around 220,000 ha of forestry in the East Coast Tairawhiti, Wairoa region and if 3.6% (28 year cycle) is harvested annually and yields 600 tonnes per year, 9% is around 428,000 tonnes of slash produced annually.

Somewhat less than the GDC statement but still a lot of slash ‘resource’ never-the-less.

On top of this are the pruning’s and thinnings done before we arrive at the harvesting stage, so perhaps that could be where GDC get their figure. Much has been made about the lack of economics in ‘salvaging’ slash for other uses and helping to alleviate the impact of floods. However, the government has spent over $10m alone on subsidised slash removal to get rid of 70,000 tonnes which comes to $145 per tonne. A quick look at forestry returns shows the average return per tonne of harvested forestry is around $130 per tonne. And there has been considerably more spent elsewhere and at other times on slash removal.

Source: Figure.nz

So, what this shows is that the 70,000 tonnes which is about 12% of the annual slash production is a drop in the ocean and the cost of removal is way out of proportion to the returns from forestry.

To me, this creates a bit of a problem for forestry, regional councils and government about what they are going to do about it in the future.

Quite a bit has been said about the introduction of a bio-energy plant some where in the East Coast region to utilise the slash in some form of mode more useful than just building huge bonfires along what used to be pristine beaches. I was recently in Fiji and en-route to ‘resort’ we drove past the Nabou Bio-energy plant.

Established with support from South Korea, the plant utilises 300 tonnes (depending upon dryness and may be now greater with an upgrade taking place) of timber waste daily. The aim has been to supply upto 35 MW of electricity annually (Which I think is about ¼ of the “First Light” supply to the Tairawhiti region). The total cost of the Nabou project in 2016 was put at US$45 mln.

If I took a punt and said it costs energy companies about 15 cents to produce a kwh at 35,000mwh that’s a $5.25 mln return annually, or if 90,000 tonnes of slash are utilised (300 tonnes per day x 300 days) then a return of $58 per tonne. No doubt someone with better information could drive a train though this but it does make you wonder why given how long the East coast has had a major and growing problem with slash why something more positive hasn’t been done sooner.

Putting a cost on slash will no doubt bring a lot more potential solutions to the table and power generation may just be one of them. But what we do know is that something creative needs to be done and throwing good money after bad cleaning up after weather events is not a solution.

The slash from forestry is also only part of the problem and while possibly the greatest and most damaging percentage of timber in water ways, given the eroding nature of the geography in the region there is also a lot of indigenous, poplar and willow that’s ends up flowing towards the coast.

The LinkedIn report of 2020 damage to the Tikapa beach and slippage on surrounding hills testifies to. So a potential timber resource for bio-fuel is likely to be considerably greater than the theoretical numbers. Fiji not only uses waste timber but has local coppicing forests to also provide fuel.

A project like bio-fuel in conjunction with utilising slash would have be a likely candidate for the now (it appears) defunct Climate Emergency Response Fund (CERF).

In addition to the new slash requirements, the government has announced a new $30.25 per hectare charge for forests, as well as new fees for 22 services, such as changing the classification of exotic or indigenous areas and asking for more time to collect forest measurements. Needless to say, forestry companies are not happy about the new charges and hit back, saying the levy is another government disincentive to plant forests when they are most needed.