Tuesday, 28 June 2016
Australian nonsmoking plant
Native Tobacco grows in rocky places throughout the eastern two-thirds of New South Wales and all but the north-central chunk of Victoria, in the Arid and Home Gardens at Cranbourne Gardens, and at least temporarily in my front garden at home.
As is the want with this kind of common name, 'native tobacco' only makes sense in the local context and the plant is also sometimes referred to as Australian Tobacco (despite learned publications sometimes using the name Austral Tobacco surely no-one ever says 'Austral' commonly).
Nicotiana suaveolens, as botanists call it, is a lanky annual up to one and a half metres tall, with long tubular white flowers. Another local species, Nicotiana maritima, is similar but is covered in woolly hairs, has generally smaller flowers and never gets more than one metre tall. Although relatively widespread and common in South Australia, Nicotiana maritima has only been confirmed from a few scattered locations in Victoria and may now be extinct.
However ... while the plants photographed here are definitely not woolly, they do have some soft hairs at the base of leaves and around the flowers. It's this trace of hairiness and the difficulty in using things like plant height as a taxonomic character (all plants have to be small at some stage of their life, and may be stunted in conditions are not ideal) that leads some botanists to be a little sceptical of these two being separate species. An overlap in flower size, the other diagnostic character, doesn't help.
Those that know both species better say there is more to it and the flowers may have some further subtle differences. Conservation botanist Neville Walsh is growing up seed of both species at the moment to do a direct comparison. Depending on the outcome of this experiment it may be that we don't actually have, and perhaps never have had, Nicotiana maritima in Victoria, just a bit of variation in Nicotiana suaveolens.
Either way, the Australan Tobacco is a tobacco plant, but not one that people tend to smoke. Commercial tobacco comes from Nicotiana tabacum or Nicotiana rustica, both from tropical and subtropical America (the former of hybrid origin). Nicotiana tabacum sometimes escapes from cultivation and becomes established in bushland, but it tends not to persist. (These are the opened fruits of Nicotiana suaveolens:)
Since 2006 it has been it has illegal to grow either species, or Nicotiana sylvestris, in your home garden in Australia. This is because such plants are used for 'smoking, chewing or snuff' and therefore considered 'to be tobacco plants for the purposes of the 1901 Excise Act'.
While the Aregentinian species Nicotiana sylvestris is not grown commercially, there appears to be a small trade in it as an ornamental plant and promotion of it as a source of smoking/chewing/snuffing tobacco. It appeared as a weed in central Victoria in the 1960s but has not been recorded since.
Expert advice is that if other species of Nicotiana are developed so their leaves can be used in similar ways then these too would be considered tobacco plants, and should not be grown.
As things stand it seems you can grow Nicotiana suaveolens, but please not ingest it or its vapours in any way.
Images: These photographs were taken in the Growing Friends Nursery at Cranbourne Gardens in early May.