Growing a forest of maple trees in North Otago

March 6, 2024

In the Tree Syrup Aotearoa research programme, we’re focusing on the potential of young trees for making maple syrup. Our aim is to use a closely spaced, horticultural-style row-crop, similar to an orchard or vineyard, and to trial new pruning techniques that result in smaller plants with multiple narrow shoots, ideally suited to modern vacuum harvesting techniques.

But we’re not the only ones in New Zealand interested in maple syrup. Entrepreneurial landowners are also investing in traditional growing methods which use mature, forested trees. We caught up with the Armiger family in north Otago to find out how their maple plantation is going.

Aerial photo of the young tree taken by drone, Febuary 2024.

In 2020, the Armiger family planted close to 500 sugar maple saplings, with the long-term vision of creating maple syrup from a forest of mature trees. This is similar to the approach taken by Dave DeGray​ near Nelson. He started planting sugar maples in 1984, and reached tappable girth for collecting the tree sap in around 20 years.

The Armiger family’s 50 acre property is located 40 kilometres inland from Oamaru. They run some cows and sheep and were looking for diversified revenue options. They didn’t want to plant nuts (because of the rodents), but maples, and making maple syrup, seemed to fit well with their climate and conditions.

The property is about 280 metres above sea level, and has cold nights (the fire goes on in the evenings for 200 days per year). They dedicated a 10 acre block to maples. Having the trees planted throughout the property has been great for testing different conditions. Their land is mostly flat with a river/creek at one end. The trees have done the best in stony or sandy soils, especially near the river, and have been slower to establish in the clay soils.

Young maple saplings growing in north Otago.

The trees have had no fertiliser since planting, but have been manually watered in the summer season. It takes 3000 litres to water them all! Once they reach chest height, the trees are considered established and no longer get watered.

The family haven’t had any possum or rabbit issues. The plant guards, corrugated and about 700mm high, have done their job (though the Armiger family do not recommend the triangular profile as this catches the wind). Untreated sticks and netting were not robust enough, rotting away, as did different weed mats (having tried coconut and wool options).

The biggest pest problem is a grass grub that eats new growth and creates deadwood. They’ve tried various sprays and pruning, with mixed success, but this is difficult to manage at scale. They expect to have to buy about 50 replacement trees this year due to this pest, but are hopeful mature trees with better withstand the damage.

The Armiger family have embraced an experimental approach to this project. As well as trialling different soil types, locations and pest control options, they’ve also planted some pine trees nearby as a comparison, to use as a side-by-side test to monitor tree growth over time.

Their goal is for full size trees, which they will harvest with a network of taps and tubing systems. One day, they hope to have a sugarhouse and visitor centre, and we look forward to seeing them realise this venture.

It takes 3000 litres to water all the trees in the dry season.

All photos were provided by the Armiger family.

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Plantation Management
NZ Trial Sites
Business Case & Economics