By Marilyn Wightman
With over 40,000 different plant species in the world many of these have proved to be beneficial for the human population and have accordingly been recognised for their goodness and elevated to join the plants that we call herbs.
Most of us have used ‘pine scented’ products in the smallest room of the house to cleanse and purify. (Those inclined to less chemical cleansing can always add drops of essential oil onto a dry pine cone and have this fragrance stationed on the toilet windowsill as an alternative.) The scent of pine needles when walking under forest trees is exhilarating.
Perhaps it was the month spent in the northern hemisphere’s winter recently that has influenced the next few herbal topics. That time among Californian redwoods certainly left an impression of what a privilege it is to live in this more temperate part of the world. And as winter approaches here, it will be good to see a different green winter world outside the window.
In honour of the many New Zealand native members of the worldwide conifer family, the first group to consider is the Podocarpaceae family, which mainly grows in the southern hemisphere, including Asia, South America, Australia and the Pacific Islands. All the New Zealand examples are typical of conifers, with narrow leaves and evergreen habit. They are all long-lived and renowned for their timber. They have fleshy fruit, however, instead of hard pine cones. Most New Zealand podocarps are dioecious, with separate male trees bearing strobili and female trees having ovules.
Another unique New Zealand feature of these southern conifers is the Latin names they retain. These tell the stories of the discovery of previously unknown plants in the late 18th century and early 19th century explorations of the forest covering this land. While Cook’s expeditions were in the late 1700s, both JC Bidwell and Allan Cunningham came searching for new plants in the 1820s.
Rev. Colenso also is attributed with finding and naming many native trees when he walked the country with his missionary work.
And something even more special is the additional Maori generic common name.
Many of the following trees had special uses among the Maori. The fruit was edible and birds feeding on the berry were prized for their resulting wholesome flavour. Some of the wood was flexible and pliable so was used in making bird snares and fishing rods. As conifers, they contain natural turpentines and scented resins. These were used for therapeutic steam baths where the volatile oil evaporated and were absorbed by the skin and inhalation. In modern times the chemicals the podocarp family contain continue to be researched and identified for their herbal use. Taking the broader definition that “a herb is any plant that has a use”, the New Zealand conifers of this group have already provided shelter and housing from Maori people to present-day people.
Totara was one of the selected herbs for this year’s (2013) Herb Awareness group.
Dacrycarpus
Dacrycarpus dacrydioides (formerly known as Podocarpus dacrydioides) is kahikatea or white pine. European settlers quickly discovered the timber was prone to borer attack so dismissed it in favour of other timber for construction. But it played an important part in the export trade of New Zealand produce. White pine made excellent packaging material and was used for fruit boxes and cheese and butter exports as the wood did not taint the dairy product. Maori used the tree to harvest the bounty of fruit that was eaten raw. Men would climb these forest giants and collect the fruit in baskets which were lowered to the forest floor. These were emptied and the men, still positioned in the trees, would retract the cord, pulling the basket up to be refilled. Burning the resinous heartwood, the resulting dark charcoal was powdered into pigment used in tattooing. Rather than typical pine needles, the leaves of many of the Dacrydium group are small and overlapping. They are s calelike, similar to the leaves of macrocarpa.
Darcrydium
Dacrydium cupressinum, red pine or rimu, is one of New Zealand’s fossil trees that has been dated back 70 million years. Podocarp forest once covered much of New Zealand and rimu was one of the prevalent trees. It is one native tree that grows the full length of the country. Much prized for its hard wood, many state houses built in the mid-1900s were constructed of rimu, and much locally made furniture of the same time used this timber.
Halocarpus
Halocarpus bidwillii, bog pine or mountain pine, is an unusual tree. While getting about four metres high, the side branches often droop and touch the ground where new roots form. These then repeat the growth pattern, so often a mature bog pine will extend to form a multiple shrub that can extend over a 50 metre round area.
Halocarpus biformus, or yellow pine, has sweet perfumed wood.
Halocarpus kirkii, or monoao, looks similar to kauri and is confined to a small area between Hokianga Harbour and Coromandel.
Lagarostrobos
Lagarostrobos colensoi, or silver pine, grows at the top of both islands. Like many of its cousins it is slow growing and is a hardwood.
Lepidothamnus
Lepidothamnus intermedius, or yellow silver pine, is another hardy podocarp that grows to 900m above sea level and is spread the length of the country. The timber is highly inflammable and contains a red resin.
Libocedrus
Libocedrus plumosa, or kawaka, is a podocarp that has both female and male cones on the same plant. Libocedrus bidwillii, or pahautea, prefers wetland forests and grows only in the Nelson area of the South Island and from Rotorua north in the upper island. The bark falls off in long strips and was useful kindling in starting fires.
Phyllocladus
Phyllocladus aspleniifolius var. alpinus , or mountain toatoa, has strongly aromatic foliage. This is one podcarpus that has male and female cones on the same tree. As variations of the form keep appearing, the names continue to change. Phyllocladus glaucus, or toatoa, and the trees of this genus do not have the typical scaly overlapping l eaf form but have cut and lobed phylloclades. These are somewhat similar to gingko tree leaves. Phyllocladus trichomanoides, celery pine or tanekaha, is so named for its large phylloclade leaf form which has toothed margins similar to celery leaf. The wood of this tree is pliable so is ideal for bent wood construction such as bridges or rods.
Podocarpus
While there are over 100 species in this genus just five are endemic to New Zealand. Podocarpus totara is the most well known conifer of this genus retaining its Maori name in Latin. It grows to an altitude of close to 600m, and then Podocarpus hallii flourishes above this altitude. Maori knew this tree well and prized the timber for its many uses. All canoes – war, river and fishing – used this wood. Many of the carving decorations on whare and pataka were on this wood. The bark was used for basket-making, food boxes and also for storage vessels to contain muttonbird and fruit. European settlers used the timber for roof shingles, fencing timber, telegraph poles, house piles, wharf piles, framing and bridging. Podocarpus hallii, or thin barked totara. The inner bark was stripped away and moulded into package bags to preserve titi (muttonbird.) This has now been renamed as montane totara and reclassified as Podocarpus cunninghamii. Podocarpus lawrencii is indigenous to mountain areas of much of South Island. Podocarpus nivalis, or mountain or snow totara. This was distinguished by Bidwell in 1839 when he was climbing Mt Ngauruhoe.
Prumnopitys
Prumnopitys taxifolia, matai or black pine. Floorboards of houses built up until the 1970s were often matai flooring as the wood was prized for its durability and hardness. Prumnopitys ferruginea, miro or brown pine. Not as well known, miro was used in furniture and flooring too.
Notes
Many books have been published by authors with specialist knowledge of New Zealand’s unique flora. Taxonomists revised the classification of podocarps in the late 1990s. There has been a lot of renaming which lists some of these conifers under a differing genus. My favourite two authorities – JT Salmon and LJ Metcalf have differing names for the podocarps. If an older book is being sourced there will be Latin name variations.
There is a forgotten group of people who dedicated their working lives to ‘timber cruising’ which was part of NZ Forestry Service. This service began in the early part of the 20th century when it was realised that harvesting natural New Zealand timber needed to be managed towards a goal of sustainability for future timber needs. Establishing exotic forests with fast–growing species needed to be measured against the regeneration of native forests, to maintain a forest that ensured a wood resource into perpetuity, which was the start of the pine forest industry here. Forward-thinking government and business people realised the importance of seeding non-productive areas of land with exotic pine forests.
In native forests old Lands & Survey boundary lines were used to measure off an area and create a series of grid lines within the boundaries of the forest to be milled. The timber cruisers – usually 3 or 4 men – would then survey each block and systematically measure and record the timber that was millable. Only these trees would be selectively cut for timber needs.