by Tony Orman
Waihopai valley farmer and conservationist Murray Chapman says the Molesworth Station wilding eradication programme is doomed for failure if the core sources of the Molesworth seed spread are not removed.
“How can this Molesworth investment ever be future proofed if you do not deal with the core source of the threat, i.e. the Waihopai, Leatham and Branch catchments?” he said in a recent presentation to the Nelson Marlborough Conservation Board.
In an attempt to safeguard the iconic Molesworth Station the Government and the Department of Conservation are now proposing to create a buffer zone to prevent seed spread from the Waihopai, Leatham and Branch rather than targeting the source.
“It has been proven beyond doubt that buffer zones do not work simply because of the huge distance seed travels in wind events and the only way to future proof is to remove the parent material that are the source of the seed rains,” said Murray Chapman. “Seed only has a viability outside the cone of around 5 years so the cycle can be broken if parent seed source is removed.”
However Murray Chapman also expressed concern at the perceived inaction over decades.
Recently he tramped up the upper Waihopai valley just as he did in the 1980s. In 1984 there was not a conifer in sight apart from two small Forest Service planting plots.
“But wilding pines are now invading the high country with no real action in those intervening 40 years,” he says. “We are going backwards faster than ever before and inaction has facilitated this dire state.”.
In his presentation, Murray Chapman took aim at the current coalition government’s proposal for the Minister of Conservation Tama Potaka to rush through legislation before the 2026 election. The proposal would effectively make 60 percent of the public’s conservation estate eligible for being privatised and sold off under the guise of perceived low conservation values.
“Its a deeply flawed proposal because of a political agenda that degrades the intent of the Conservation Act,” he said.
Murray Chapman urged the conservation board and the New Zealand Conservation Authority to listen to the public.
“The recreational and conservation public need our voice to be heard,” he said.
“Successive Governments have continually undervalued the public’s Conservation Estates against the expectations of New Zealanders, something you have allowed to happen.Why have you allowed this when conservation and recreation groups have loudly voiced their concerns?”
The coalition government’s proposal would also appear to remove Conservation Boards and the New Zealand Conservation Authority, in other words the public’s voice, from the equation giving the Minister all the power.
“That is something we as a recreational and conservation community would vigorously oppose and I hope you would vigorously oppose as well.”
Murray Chapman reminded the Nelson Marlborough Conservation board that nine years ago he said the board was “asleep at the wheel.”
“Sadly nothing seems to have changed,” he concluded.
My main concern is the hypocrisy of carbon farming where gross polluters (e.g. Air NZ) can get a “licence” to continue polluting by setting up carbon farming, taking food productive farms out of existence and setting up a seed bank for wilding pines. I note
Minister McClay doesn’t mention wilding pines in his press release!
With reference to Ian Tapply’s comment ;- Australian scientist Ian Plimer said :- “Climate change politics is religious fundamentalism masquerading as science. Its triumph is computer models unrelated to observations in nature. There has been no critical due diligence of the science of climate change, dogma dominates, sceptics are pilloried and 17th Century thinking promotes prophets of doom, guilt and penance.”
Water is a precious resource. The consequences of wilding pines are loss of productive farmland and precious water resources as they are very thirsty trees. Farmers, anglers, indeed everyone should be alarmed at the dewatering of streams and rivers.
Tens of millions are spent by DoC on dubious 1080 poisoning ventures, and they don’t have enough money for the most obvious threat to conservation values i.e. wilding pines. Minister Potaka is truly asleep at the wheel.
There’s strong international (and NZ) evidence backing the key points in this post by Tony:
• Seeds travel far, so narrow ‘buffer zones’ are not enough. Field surveys in New South Wales documented radiata pine establishing several kilometres from plantations, with longest recorded distances ~10 km; once sources are upwind, seed keeps arriving (Williams 2009). Management models likewise show buffers fail if dispersal exceeds the buffer width—one must treat the occupied zone and remove sources (Moody & Mack 1988; Eppinga et al. 2021).
• Remove parent seed sources. Classic invasion control work shows eliminating source stands and small ‘satellite’ patches slows spread markedly (Moody & Mack 1988; Eppinga et al. 2021).
• Water yields decline where pines establish. Decades of paired‑catchment studies report substantial reductions in streamflow after conifer afforestation (Bosch & Hewlett 1982; Brown et al. 2005). South African national assessments quantify large runoff losses from invasive pines and other trees (Le Maitre et al. 2015, 2016). NZ synthesis also documents widespread radiata pine invasions across climate zones (Bellingham et al. 2023).
• Seedbanks persist for years, so follow‑up is essential. NZ wilding‑pine guidance advises conifer seeds in soil can remain viable for at least 5–6 years, requiring multiple maintenance passes after adult removal (Wilding Pine Control Handbook 2024; ORC 2022). Experimental work on serotinous pines shows buried cones and soil seedbanks can remain viable for years (Teste et al. 2011).
Bottom line: the science aligns with the farmer’s wake‑up call—deal with the upwind seed sources, don’t rely on narrow buffers, and plan for several years of follow‑up to exhaust the seedbank, not just a one‑off sweep.
References (open‑access where possible)
1. Williams, M.C. (2009). Pinus radiata invasion in New South Wales: the extent of the problem and issues for management. Plant Protection Quarterly 24(4):146–156. (Reports dispersal up to ~10 km).
2. Moody, M.E. & Mack, R.N. (1988). Controlling the spread of plant invasions: the importance of nascent foci. Journal of Applied Ecology 25:1009–1021.
3. Eppinga, M.B. et al. (2021). Spatially explicit removal strategies increase the efficiency of invasive plant management. PNAS Nexus (open access).
4. Bosch, J.M. & Hewlett, J.D. (1982). A review of catchment experiments to determine the effect of vegetation changes on water yield and evapotranspiration. Journal of Hydrology 55:3–23.
5. Brown, A.E., Zhang, L., McMahon, T.A., Western, A.W., & Vertessy, R.A. (2005). A review of paired catchment studies for determining changes in water yield resulting from alterations in vegetation. Journal of Hydrology 310:28–61.
6. Le Maitre, D.C., et al. (2015). Impacts of invading alien plant species on water flows at stand and catchment scales. AoB Plants 7:plv043 (open access).
7. Le Maitre, D.C., et al. (2016). Estimates of the impacts of invasive alien plants on water flows in South Africa. Water SA 42(4):659–672 (open access).
8. Bellingham, P.J., et al. (2023). The right tree in the right place? A major economic and environmental threat from invasive radiata pine in New Zealand. Biological Invasions 25: 783–799.
9. Wilding Pine Control Handbook, v2 (2024). Wildingpines.nz (NZ National Programme guidance): seed in soil viable ≥5–6 years; plan multi‑year maintenance.
10. Otago Regional Council (2022). Wilding Pine Control Methods (A5 booklet): notes soil seed viability 5–6 years and need for repeated maintenance passes.
11. Teste, F.P., et al. (2011). Viability of forest floor and canopy seed banks in Pinus contorta var. latifolia forests after a mountain pine beetle outbreak. American Journal of Botany 98(3):630–640.
NZ is doomed. Wilding pines are everywhere. New plantations are everywhere. Old plantations uneconomic to harvest are left as seed producers. Wilding pines here in the Marlborough sounds are appearing again after millions was spent ridding the last ones. Their offspring are now pushing through the canopy and in a few years will be seed producers unless millions more is spent. It’s a vicious cycle we just cannot win. The only way forward with a glimmer of hope would be using GMO seedlings that cannot reproduce if left. Then all future forests will not contribute
This disaster is because of the N.Z. Forest Service &. Catchment Boards. – pre DOC disaster. This whole 1080 program is similar disaster in the making! We’ve witnessed these environmental disasters from the beginning- it’s got to stop!
Stupid and short sighted.