The Science and Romance of the Cabbage Tree

Forest and Bird, Issue 299, 1 February 2001, Page 4

The Science and Romance of the Cabbage Tree

— Gordon Ell.

hilip Simpson is a scientist also has a romantic affection for his life-long study, the cabbage tree. Now he has combined the science and art of this New Zealand icon into a biography of the tree Dancing Leaves, The story of New Zealand’s cabbage tree, ti kouka (Canterbury University Press). As one of the scientists who studied the sudden decline, which began killing these landmark trees in the 1980s, he also feels a personal loss; of stories, of art, of a symbol of New Zealand. The image of a cabbage tree blowing in the wind, indeed the sound of its rustling leaves, is ingrained in the New Zealand psyche. ‘Everyone, he says simply, ‘has a cabbage tree story. ‘I see the loss of these trees, through disease and development, as a tragedy -a loss of national identity, he says. Dancing Leaves is a large format, full-colour tribute to the tree; something quite different in writing about nature in New Zealand, in the way it combines good science with the arts. Dr Philip Simpson explores the ancestry of the New Zealand Cordylines — like the podocarps they date from the Age of the Dinosaurs — then pursues their cultural history through Maori

and subsequent times. Maori use of ti kouka as a food source, and material for baskets and cloaks is examined, along with illustrations of places and artefacts from early times; subsequent European uses are also documented. Central to the book are human stories about the trees. There are chapters too about cabbage trees in design and art, and in literature. There are literally hundreds of colour pictures in a book which, at 324 pages, still represents a much cutdown version of his original manuscript. The progressive loss of trees from sudden decline, and the prospects for their restoration, provides an ecological challenge. ‘I was part of the debate between scientists, as to why the cabbage trees were dying off? says Philip Simpson recalling the genesis of his work. ‘Some said the reason was the sudden decline disease caused by a phytoplasma bacterium spread by the introduced vinehopper. Others argued the trees died because of ecosystem destruction weakening their hold on the land. ‘I was on a Ngatiwai marae in Northland when an elder said "the tree has lost its mauri". This Maori perspective, that the trees had lost their life force, summed up the situation in a nutshell — both scientific arguments were correct, and the Maori perspective tied the fate of the dying trees to our ecological health. You can’t drain 90 percent of our swamps, destroy baby trees, and expose older trees to development, without epidemic consequences. What we had was not "sudden decline" but "slow decline".

Philip Simpson who had worked as a scientist on ‘monocotyledons with secondary thickening in their stems’ (his PhD was written about the broadly related Joshua tree, icon of the Mojave Desert) now turned to studying the cultural history of cabbage trees. Obtaining a Stout Research Fellowship, he advertised for personal stories ‘about cabbage trees, and I got hundreds... ‘Because the tree is so widespread it seems to be the major species with which New Zealanders identify their homeland’ He also gathered a wealth of anecdote and art about cabbage trees, set off in the book by pictures ranging from landscape painting to postage stamps and trade marks. ‘Sadly, thousands of trees are still dying on our farms and cities, and there is no way they can replace themselves nat-

urally because there is no natural habitat, Philip Simpson says of the future for cabbage trees. We've done well setting aside 30 percent of our countryside in national parks and reserves, but the occupied part of New Zealand is an ecological desert. ‘Cabbage trees are a bush-edge plant — they belong in wetland remnants, on riverbanks and along coastlines, all habitats under great stress. Their best prospect is for us to replant our riverbanks. There’s multiple advantages here, including improved water quality, arresting erosion and creating natural corridors for nature through the countryside. Because they’re still common, many people don’t realise cabbage trees are at such risk. I hope this book will mean people won't be able to say too late "I did not know" about the

crisis they face.