Boggy Creek is boggy no longer
After 16 years of planting natives along waterways and fencelines on their Central Canterbury dairy farm, the Garrett family say the results to date only encourage them to do more.
Adding native plantings has not only improved the health and clarity of their drains and waterways and the aesthetic appeal, it also provides an example to others of what can be achieved while running a successful dairy farming operation.
Only 1km lies between the Garrett farm and Te Waihora Lake Ellesmere, the main outlet for drains and waterways on the Central Canterbury plains and one of New Zealand's most significant wetland systems.
Phil Garrett and his family milk 900 cows year-round and farm 1200 cows in total on their 440-hectare irrigated Rushbrook Farm near Doyleston. He farms with his son Andrew and daughter-in-law Amanda.
Their son Ethan also works on the farm, while daughter Alanagh lives at home but works in Christchurch.
Because of the farm's proximity to the lake, it has a high water table and is prone to wet conditions in winter, prompting the Garretts to build a 900-cow free stall barn to winter their herd. Completed in winter 2012, the barn was well worth the expensive price tag, said Phil Garrett.
"We use the cow barn to keep cows off the ground in winter."
Cows are only outside during the day in winter when the weather is fine. In summer, cows are outside all the time.
"We get everyone else's water as there is a big gradient from Dunsandel to here. But our soil type - Waterton clay loam - dries out in summer like rock."
Effluent storage totalling 12,000 cubic metres means effluent is sprayed on paddocks only when conditions are dry.
As effluent is applied over the entire farm, no bought-in fertiliser, including nitrogen, has been used for the last two years since the barn was built. Production has lifted 40 per cent compared with two years ago and nitrogen leaching dropped from 16-18kg nitrogen loss to groundwater per hectare to 6-8kg/ha.
"This is attributed to housing cows. Soil tests show what we are doing is working. We only have to add sulphur and trace elements."
The Garretts grow maize and buy in maize and lucerne for silage to provide a balanced diet for cows.
When Garrett first came to the farm 28 years ago, Boggy Creek - the main waterway through the property - was completely clogged with willows and gorse.
Once this was removed, former Environment Canterbury field officer David Hewson provided advice on planting natives.
"There was some opposition on the basis that this was 'gardening on the drain' and would impede water flow during floods, but this was not the case. We only plant on the banks, not in the drain."
The success of this inspired him to continue and his family have now planted nearly 1.5km of drains and streams on their farm as well as a "wildlife reserve" of a hectare on the farm and a patch of flax plantings.
The Boggy Creek plantings are well established and the native carex and flax have reduced the need for ongoing drain clearance by shading out many of the weeds. Their work was recognised with their winning the 2014 Diana Isaac Cup for native planting in the Selwyn District, where less than 0.5 per cent of natural land cover remains.
Te Waihora Lake Ellesmere is one of five key catchments nationally being improved as part of a joint $20 million, 10-year DOC and Fonterra partnership. Garrett estimated $20,000 had been spent by his family on fencing and planting, including keeping areas clear of weeds when plants were small.
"Gorse, blackberry and hawthorn are all very invasive and take over if you are not careful." This is in addition to funding from ECan's enhancement fund and the DOC-Fonterra partnership.
"Our family have also planted our Leeston to Christchurch highway boundary in natives, replacing an old pine shelterbelt. This is starting to take off after two years of growth. Our Hanmer Road boundary is partly planted with cabbage trees and this is a continuing project. One of the main successes is the planting of internal drains with carex secta. Our best and biggest project is Boggy Creek, of which we are very proud.
"Having our work recognised in this way is very gratifying and we acknowledge the great contribution the late Lady Diana Isaac made to conservation in Canterbury," said Garrett.
Native plantings enhance stream health and protect banks from erosion, as well as filtering sediment and some nutrients from paddock runoff. An important trout spawning stream, a survey counted 24 redds in this 1.8km stretch of Boggy Creek in 2005, compared with only six in 1984.
Garrett said pollution in Te Waihora Lake Ellesmere was highly overstated.
"There are thousands of birds on it. It is a living lake. Because it is so shallow it is always murky as the wind stirs it up.
"Politicians tend to jump on water quality issues at Lake Ellesmere. The lake is not in a bad state. There is sediment and some nitrates and phosphates, but it is teeming with fish and eel. They export eel and flounder from the lake. Which is not to say we should not make it better.
"There is a lot more work being done by farmers, particularly on Boggy Creek."
Nicola Toki, Fonterra South Island project manager community investment in water, who nominated the Garrett family, said they were an outstanding example of how a successful farm can include native plants as part of the landscape and in a way that complements their land without interfering with daily farming practice.