Rangiatea Station Run Off

May 2009

Reducing nitrogen run-off from a farm near Lake Taupo

Lake Taupo is a unique New Zealand icon, and the purity of its water is part of its immense value as a resource for fishing, water sports and tourism. Research has identified that nitrogen from farming operations is a major controllable source of contamination, and Environment Waikato is proposing that each property have a Nitrogen Cap based on the estimated average annual N contribution of each farm in the five years to 2005.

This is seen by some people as unfair. Over the past 30 years various government entities (Lands & Survey, Maori Lands Board, Marginal Lands Board) have encouraged the clearing of the land and the development of pastoral agriculture. Now officialdom wants to turn the clock back, or so it seems. Also, sheep and beef farms that have a nitrogen input of perhaps 12-18 kg/ha are being capped at that whereas dairy farms that produced 25-35 kg/ha are being capped at a higher level. Is that fair?

According to Geoff Burton, a farm adviser who has worked in the region for decades, the problem of excess N going into the catchment essentially boils down urine discharges, particularly from female cattle. Unlike sheep and deer, they urinate in large quantities in one spot, and it is this high concentration of N that cant be readily absorbed or dealt with by pumice soils and that probably ends up in the Lake. Some farmers have consciously avoided going into dairying for this reason, while others have reduced beef breeding herds and substituted deer. Should they be penalised by being capped at the highest 2000- 2005 N level?

Central and regional government are naturally concerned about Lake water quality and have sponsored the setting up of the Lake Taupo Protection Trust (LTPT) that aims to reduce the amount of N going into the Lake by 20%. Trust CEO Graeme Fleming says that it is doing this by encouraging farmers to change the way they farm and by buying available land and diverting it into forestry or other low N output land use.

However, not all land is potentially available for purchase. Maori incorporations and trusts control about half of the land in the Taupo catchment. They and private owners who do not wish to sell to the Trust are being encouraged to change land use by retiring steep and marginal land, fencing off gullies and areas of native bush, planting trees and substituting deer, sheep and male cattle for cows.

One of the incentives for doing this is the ability to sell N entitlements within the catchment. For example, if a farm with an N cap entitlement based on dairying changed from back to sheep and beef there would be an N reduction of around 20kg/ha. That entitlement could be sold to another farmer in the catchment. The other incentive is the carbon sequestration involved in forestry. Whether or not carbon credits earned this way could be sold is uncertain at present and depends on the outcome of the governments review of the Emissions Trading Scheme.

Rangiatea Station is not holding its breath until the government makes a decision. As a large tract of Maori land with multiple ownership it will never be for sale, and its management committee takes a holistic view of caring for the land and people as well as the Lake. To achieve this they are looking hard at ways of making the maximum sustainable profits using environmentally friendly farming policies.

The Station is around 4328ha in a long, narrow strip that runs from the Lake shore up to the top of the catchment and over into a neighbouring catchment. Currently the land use is as follows:

Lucerne 35

Pasture 1506

Plantation Forestry (mostly 13yr old) 526

Retired conservation areas (to protect Lake Taupo water) est 800

Indigenous forest (largely developable) 1461

TOTAL 4328 Ha

This year it will winter 17,000 su on 1541 effective hectares (11.1 per ha). Stock will comprise 6,000 ewes and replacements, 430 cows and replacements, 980 hinds and replacements. Sheep to cattle to deer ratios will be 51:27:22. This is a massive improvement from when the Trust took over from Maori Affairs management in 1990.

Geoff Burton believes it is the most challenging property to farm in the catchment because it goes from the lake edge at 360m above sea level where it is dry and windy with fragile pumice soils to a medium section at about 600m of slightly higher soil fertility, and the highest third of the property is at 800 to 1000m and is very cold in winter. The rainfall varies too, from around 1400mm near the Lake to about 1900 in the middle section, and 3000mm in the top country.

The length of the block and the variation in height above sea level, temperature and rainfall are both a weakness and a strength of the property according to farm manager Colin Gates.

It has a longer winter than most farms in the North Island and it is very bleak at the top, so stock are wintered lower down, and then as it warms up the stock are moved back up the property. The shape means you can't just decide to go graze a paddock at the other end of the place because it is getting away, you have to plan it better than that. There is only one access up to the top of the property and we have a track which we call the Golden mile, 1600 m more or less straight up, says Colin.

On the other hand, the high rainfall at the top means that it will grow grass even in a drought and makes us summer safe, so that is a big plus for the property.

The imposition of an N cap will make life more difficult for the management committee, but chairman Dominic Otimi says they are are dealing with it and we are not going to muck around with the issues that surround the specifics of this land change use.

Dealing with the weather, rising expenses, increased local government compliance costs, environmentalists, are all hassles that we have to cope with, but coupled with that we have overseas customers that see what we do as natural farming, raising animals and the outdoors on clean pastures and providing clean water. What we do is as close to organic farming as we can get, and we are going to take every opportunity to maximise our marketing potential with the clean water of the lake and the pristine mountains as our strong selling points for our products. With that story behind us they will always command a premium, he says.

Currently we are about to start investigating nitrogen and carbon farming scenarios that are appropriate to this place. So our aim is to farm sustainably and profitably in perpetuity. Our committee has been looking at a number of farming system options here and we want to see the results of the various options before we make too many changes, and these will be based around the theme of reduced farm area, altered stock policy, carbon farming (trees) and release of capital from the farm with nitrogen when nitrogen is not needed.