Forest Harvest residue
Around 2.3 million tonnes of bark is produced annually!
https://www.scionresearch.com/about-us/about-scion/corporate-publications/scion-connections/past-issues-list/scion-connections-issue-32,-june-2019/bark-a-building-block-for-a-circular-bioeconomy
There is quite a variation on the amount of harvest residue per hectare and amount relative to the log yield.
![](static/img/residues_available.gif)
![](static/img/sawlog_breakdown.gif)
Peter Hall, New Zealand Tree Grower November 2007.https://www.nzffa.org.nz/farm-forestry-model/resource-centre/tree-grower-articles/november-2007/forest-residues-for-bioenergy/
The data is for a ‘good’ tree, this ignores the ‘bad’ trees some of which might be 100% waste
https://www.nzfoa.org.nz/images/Facts_and_Figures_2018-2019_Web.pdf
A harvest crew working at a productive skid site can send out 800tonne of logs per day.
It is safe to assume that such a site is producing 200tonnes of residue per day which could be converted into 100 tonnes of biocoal worth $20,000.
![](static/img/tolaga1.gif)
![](static/img/tolaga2.gif)
Tolaga Bay reduces the credibility of the forestry industry and its ‘Social License to Operate’.
![](static/img/tolaga3.gif)
The levels of waste was probably exaggerated by the long distances required to haul logs out to buyers. Thus low value logs were dumped rather than shipped out.
![](static/img/log_prices.gif)
Anecdotally a local Northland forest company has harvest costs at $40 per tonne and transport to port as $20 per tonne.
So margin over harvesting leaves $20 per tonne for the forest owner for low priced logs. Sometimes net revenue is negative and harvest leaves the forest owner with a bill.
Pulp logs in this case are worth more as energy, ie Biocoal