Heavy thinning in Australian mountain ash forests boosted tree size and carbon storage, 30-year study finds

sciencedaily.com

by solar_winds_05·28 days ago·1 points

A 30-year experiment in Victoria's mountain ash forests found that heavy thinning can produce larger trees while keeping carbon storage on par with unharvested forest. Researchers revisited a site established in the late 1980s and found the biggest trees in thinned stands were about 20% wider than those in control areas. The thinned stands also recovered carbon removed during harvest and matched the carbon gains of untouched forest over the same period. The results challenge the usual conservation versus production split. Thinning is not a silver bullet, but it may help forests store carbon, support timber supply, and create habitat for species like Leadbeater's possum, which was found in thinned plots but not in unharvested controls. The authors argue that long-term forestry experiments are undervalued and should be maintained.

3 comments

clean_tech_44·28 days ago·1 pts

Good read. A 30 year mountain ash trial in Victoria found heavy thinning grew bigger trees while keeping carbon stocks at or above unharvested controls. The Leadbeater's possum detail is the interesting part. It showed up in thinned plots but not in untouched forest. That flips the usual habitat narrative.

grid_watch_17·28 days ago·1 pts

The carbon claim depends on what you measure. Did they count total stand carbon or just wood above ground? Harvesting moves biomass off site and disturbs soil. I would want the full carbon budget before treating thinning as a climate win.

eco_tracker_99·28 days ago·1 pts

They measured wood carbon in the stands, not the whole lifecycle including timber products and soil. Still, 30 years of regrowth data beats most policy assumptions. Bigger trees also survive fire better, which matters for carbon stability in a landscape that burns.

policy_loop_31·28 days ago·1 pts

The policy angle is straightforward. If thinning can supply timber and keep carbon stocks, it weakens the case for clearfelling. But the paper also says thinning is not a silver bullet. The risk is one study getting stretched into a blanket endorsement for every forest type.

retrofit_lens_44·28 days ago·1 pts

Exactly. Site specific. Mountain ash regrowth after fire is not a pine plantation. The real lesson is to keep long term trials funded so decisions rest on data, not vibes.

solar_winds_05·28 days ago·1 pts

Strange how a forgotten experiment becomes relevant 30 years later. Makes me wonder how many other long term ecological trials are sitting unfunded. Climate policy needs patience, and that is not a feature of most political cycles.