“The best time to plant a tree is twenty years ago. The second best time is now.” This most fabulous quote never fails to galvanise me into action and order my priorities…writes Bena Denton.
With autumn upon us, its time to plant trees, to both increase the aesthetic appeal of our landscapes and with some clever choices, also increase land value and or generate income. If you have a lifestyle block or farm, there are many options: specimen trees for beauty and legacy; tree-crops for fruit, nuts, and income; woodlots for firewood; high value forestry; manuka for the honey; riparian strips or wetlands for ecological restoration; and shelter-belts for animal wellbeing and diversity.
But where to start and why? Lets take a step back and examine the condition of our rural landscapes…we may see reason for concern. With a mere 11% of forest cover remaining in New Zealand, our landscape is vastly different from what it was 100 years ago. Anything less than 15% forest cover, critically affects long term diversity. This scenario begs us to re-examine our role as kaitiaki (guardians) of the land. As a general rule when regenerating land, we should aim for 30% coverage and of this, 30% is ideally pioneer or nitrogen fixing species to speed up the process.
Let’s start with shelter, as after permanent bush or forest, it’s the structural backbone of regenerating a landscape. I will be brief as earlier blogs have covered this area. Planting ridges and hilltops soaks water into the ground high in the landscape, which over time recharges aquifers, which in turn creates water resilience in times of drought. Plant the tallest shelter on the south boundary to buffer cold southerlies, and plant lower shelter to the east and west. Orientate internal shelterbelts north-south so as not to block winter sun. Animal health increases with shade and wind protection, and the same shelter (with clever selection) can also provide additional high mineral fodder, as well as emergency fodder for times of feed deficit. Mix nitrogen fixing trees into your shelter, such as tagasaste and alder and you are growing fertiliser on site.
Most wetlands in Taranaki have been drained and our water table severely lowered (hence we experience ‘drought’ despite our high rainfall). Far too many rivers in Taranaki are testing unsuitable for consumption even for livestock. Rivers and streams require a riparian strip at least twenty metres (not 2-5 metres) from any waterway, allowing the water to soak in and re-emerge clean in the water body. Fortunately for both wetland and riparian areas, trees offer multiple solutions.
High-value forestry may be a good choice for your land block: generating a long-term financial return and (if harvested sensitively) becoming a major contributor to river health. High-value forestry species worth considering along riparian strips are; Alnus rubra (Red alder) Acacia melanoxylon (Blackwood), Red oak, Tawa and Kahikatea. Ensure you have your site assessed for species suitability.
Woodlots are a relatively new addition to the New Zealand but are actually an ancient and sensible approach to a sustainable firewood supply. You will require only 400-1000sqm meters of land to grow all the firewood you need. Suitable firewood species in Taranaki include: Poplar, Alder (N)*, Eucalyptus, Ash, Acacia (N), Chestnut, and Japanese Cedar. A diversity of firewood species is desirable (an insurance if you will). Grouping a nitrogen fixer (N) with another species is helpful, as the N-fixer aids the growth of the second tree species. After seven to nine years, trees are selectively coppiced (cut below knee height), which produces continual multi-stems that are harvested for wood products (firewood, furniture). Growth from a coppice is faster from the original seedling, because the root system is vigorous and well established. Harvested at the right size, all you need is a chainsaw, so coppicing is a practical and economical way to produce firewood, right at your doorstep.
Specimen trees (trees selected for their beauty or for future legacy) often capture people’s imagination and give the “wow factor” to any large block of land. The first consideration is the site itself. If your land is like most in Taranaki, it’s probably bare pasture, and herein lies the problem with exotic specimen trees, as few are evolved to handle our high wind zone. While the autumn displays of colour are desirable, these European imports struggle with exposure. I have had some success with the hardier varieties like Ash, Oak, Sweet chestnut, Japanese cedar, some Poplar and Willow and Elm but even then these can be marginal. Natives offer an obvious solution, with many being outstanding in their hardiness and beauty, including; Pohutakawa, Puriri, Totora, Miro, Karaka and Kowhai. With spacing 3-10m apart, these trees are a sure bet and look great framing a driveway.
For those spots that are fully sheltered and you are looking for something special, my favourites are Gleditsia, Ginkgo, Snake bark Maple, Silver Birch, and for its flowers Chinese Dogwood. The key in selecting a specimen tree is its suitability to site conditions. And go for scale: with a large bit of land you have the luxury of planting big.
Bena Denton is an Ecological Landscape Designer and is part of the GreenBridge team. She lives with her family in Omata and is enjoying regenerating their 10acre property.
Taranaki’s landscape has been largely denuded of tree cover.
Riparian margins must be at least 20m wide to clean up run-off.