1900 to 1949

1900

• Felling of forest continues; forests now cover approximately 25% of the country which is half of what existed in 1840.
• 6,501,997 frozen rabbit carcasses are exported from New Zealand.
• The first National Noxious Weeds Act is passed to prevent the spread of noxious weeds and to enforce the trimming of hedges.
• New Zealand's second national park, Taranaki/Egmont National Park, is created consisting of 33, 543 hectares of lowland to alpine vegetation in the west of the North Island.
• The Seventy Mile Bush in the southern North Island, once 300,000 acres of forest, has been totally cut over by this time.

1901

• John Logan Campbell, wealthy merchant and farmer donates 94 ha of his One Tree Hill farm to the city that becomes known as Cornwall Park. Seven years later Campbell makes two more grants of land enlarging the park to 136 ha.
• Almost non-existent in 1890, there are now 5,000 dairy farms. In ten years there will be 15,000.
  

1902

• Lebanese immigrant A.A. Corban establishes a vineyard at Henderson which becomes a major wine-producing company.
• Hayward Wright establishes a nursery in Avondale, Auckland to propagate and select citrus and other fruits suitable for growing in New Zealand.
  

1903

• Cornwall Park in Auckland is officially opened by Sir John Logan Campbell. It consists of 136 ha and is run to this day by the Cornwall Park Trust Board. The adjoining volcanic cone of Maungakieke with 48 ha eventually becomes known as One Tree Hill Park, administered by Auckland City. Together, these form New Zealand's largest urban park.
• The 1903 Scenery Preservation Act acknowledges the need to protect endangered scenery and cultural heritage. Within two years 74 locations are visited and 7,000 ha put into reserves with proposals for a further 160,000 ha.

1904

• The first farm tractor is imported into New Zealand.
• On his Wanganui farm Alexander Allison grows seed of the Chinese gooseberry ( Actinidia chinesis) brought to him from China. In 1910 these bear small, hairy fruits, which attract attention for their flavour. Plants become available to the public in 1917.
• Grape vines grafted onto phylloxera-resistant American rootstocks are introduced.
• Himalayan tahr (Hemitragus jemlahicus) from northern India-Nepal-Bhutan are released near the Hermitage at Mt Cook for hunting; additional animals are released during the next 15 year and spread northward and southward in the Southern Alps.
  

1905

• Release of Rocky Mountain wapiti or elk (Cervus elaphus nelsoni) on the South Island at George Sound in Fiordland. These spread throughout Fiordland.
• Sika deer (Cervus nippon) are released near Taupō and become widespread in the Kaweka and Kaimanawa ranges.
  

1906

• The first edition of Thomas Cheeseman's Manual of the New Zealand Flora is published, raising the number of known seed plant species from 935 to 1415.
• Both Cheeseman and Petrie publish numerous papers describing over 100 new species between the 1870s-1920s.
• Plants of New Zealand by Robert W. Laing and Ellen W. Blackwell is published. A semi-popular, comprehensive and well-illustrated book, this went to seven editions over the next 60 years. Laing was a botanist and teacher in Christchurch with 10 publications at this time, mostly on algae. Blackwell, in New Zealand for several years, contributed much information on the plants of Northland.
• Viticulture in New Zealand by Romeo Bragato is published. This is a guide to growing grapes in New Zealand including diseases, soils and propagation that is still relevant today.
• Milling of kauri in northern New Zealand reaches a peak, when 440,000 cubic metres is cut.
• Waipoua forest in Northland is gazetted as a state forest, protecting the most extensive groves of mature kauri remaining in Northland.
• Goats are being used to control blackberry and other weeds in Marlborough and Nelson districts.
  

1907

• New Zealand becomes a Dominion of the British Empire.
• The Kermadec Island Expedition arrives on the steamer Hinemoa which picks them up 10 months later. W.R.B.Oliver collects numerous specimens including many plants.
• Donald Petrie and B.C.Aston make a collecting trip to the Tararua Range.
• The first edition of Leonard Cockayne's New Zealand Plants and Their Story is published which will undergo a subsequent four editions. This is the first attempt to describe New Zealand plants along ecological lines.
• Chamois (Rupicapra rupicapra), native to the European Alps and a gift from Emperor Franz Joseph of Austria, are released in the Mt Cook area. Further introductions take place in 1914 and they gradually increase in numbers in the following years and spread throughout the Southern Alps and as far north as Marlborough.
  

1908

• The population of New Zealand reaches 1,000,000 people.
• Completion of the railway between Auckland and Wellington further stimulates settlement and felling of forests in the central North Island.
• Flax yellow leaf disease becomes widespread. It is later found to be caused by a Phytoplasma organism.
• Opening of the Winter Garden conservatory at the Dunedin Botanic Garden.
  

1909

• The area of invasive, coastal drifting sand is estimated to be 120,000 ha as compared to 40,000 ha in 1880.
• Leonard Cockayne's Report on the Sand Dunes of New Zealand is the first scientific analysis of the spread of dunes that are encroaching upon valuable coastal pasture and croplands and the plants that stabilise them. This is followed two years later by a second report. Attention is given to the value of indigenous and introduced sand-binding plants.
• The Scenic Preservation Board begins an active phase of land acquisition which in the next 20 years results in obtaining much land along the Whanganui River and throughout the South Island; many of these are later incorporated into national parks.
• Rusa deer (Cervus timoriensis) are released near Galatea in the Bay of Plenty district of the North Island.
  

1910

• Publication of the Journal of the Department of Agriculture (later the New Zealand Journal of Agriculture) begins.
• William Douglas Cook acquires 250 ha, 30 km west of Gisborne and spends the next 40 years farming part of the land and importing a wide range of trees from around the world to develop an arboretum on the remainder of the land. This becomes known as the Eastwoodhill Arboretum.
  

1913

• Seventeen vineyards are listed throughout New Zealand, most of which are in the Hawkes Bay and North Auckland areas.
• The Royal Commission on Forestry recommends the preservation of mountain forests (protection forest) for its importance in regulating stream flow and soil erosion. Noting the sharp decline in native forests, it also recommends further experiments with exotic trees.
• Influenced by Cockaynes's report, the Lands Department begins contracting for the widespread planting of marram grass (Ammophila arenaria) in coastal areas with invasive dunes.
  

1914

• Publication of Thomas Cheeseman's two volume, Illustrations of the New Zealand Flora.
• Opening of the Canterbury College Biological Station at Cass at the junction of the dry Eastern and wet Western botanical districts 150 km west of Christchurch.
• The New Zealand Forest and Bird Protection Society is founded by Harry Ell with support from Gutherie-Smith but survives for only five years.
  

1916

• Phormium fibre exports peak at 32,000 tons. Flax yellow leaf disease begins to reduce productivity of plants.
• The New Zealand Forestry League is founded by Sir James Wilson and Sir David Hutchins to promote state forestry, afforestation and preservation of forests. It emphasizes researching the planting and cultivation of exotic trees but wise and sustainable utilization of native forests, especially the Waipoua kauri forest in Northland.
  

1918

• Otari-Wilton's Bush is acquired by the Wellington City Council for recreation and preservation of native flora.

1919

• The State Forest Service is established as a separate government department to manage state indigenous and exotic forests.

1920's

• National Forest Inventory commences, providing information about the quantity and quality of forest growth, the extent of fire damage, the effects of grazing and regional distributions of forest types.
• Possums are a protected species until this date. From 1920 until 1947 they enjoy limited protection.
• In 1925 the Government announces plans for the planting of 300,000 acres of exotic softwood. Between 1925 and 1936, 172,000 ha are planted with radiata pine in the central North Island. Private plantings add another 283,285 acres
• Red deer lose their protected status. Large populations of red deer are present in most parts of the country with widespread evidence of overbrowsing of native plants.
• Soldiers returning from the First World War receive grants to farm the land. Many occupy dairying land in North Auckland, Thames Valley and Manawatu. By the late 1920s one third of these soldiers are in financial difficulty.
• The phormium fibre industry declines because of competition from the sisal and manila industries and the effects of the flax yellow leaf disease; widespread closure of mills with the last mill closing in early 1970's.
• The export of kauri gum seriously declines due to the increasing scarcity of quality gum and because of competition from synthetics in the manufacture of paints and varnishes.
• Tobacco is now a major crop in the Motueka district.
• Hops (Humulus lupulus) cultivation is a major crop in the Nelson district.
• William Bridge, a Mt Eden nurseryman, obtains seed of the South American tree tomato (Cyphomandra betacea) and breeds a variety with appealing large red fruit; by the mid 1920s there is commercial production.
• Britain, Australia and New Zealand set up the British Phosphate Commission and proceed to strip Nauru, a former German colony, of its guano-derived rock and spread it over their own farmland.
  

1921

• Cockayne's major contribution to New Zealand botanical literature, The Vegetation of New Zealand is published. (A second, revised and enlarged edition is published in 1928 and a 3rd edition in 1958). This is the first comprehensive ecological account of plant associations in the country.
• Official opening of Trounson Kauri Park based on the original reserve established in 1890 and subsequently enlarged to a total of 586 ha.
• Government forbids the liberation of possums but illegal introductions continue into the 1940's reflecting the income generated from trapper's licences, fines for poaching and the sale of pelts.
• Cawthron Institute in Nelson opens with an endowment from the estate of Thomas Cawthron to support research on soils, plant nutrition and agricultural chemistry. This is later expanded to include the areas of aquaculture, biosecurity, coastal and freshwater ecology.
• William Herbert Guthrie-Smith publishes Tutira: The Story of a New Zealand Sheep Station. This is a highly-acclaimed account of the soil, erosion, native animals and plants, the process of regeneration and succession, the impacts of exotic plants and pests, Māori history and European occupation, based upon his experience in managing a large sheep station for 42 years in Hawke's Bay.
• Herbert B. Dobbie publishes New Zealand Ferns, the first comprehensive treatise on native ferns, forty years after his first and simpler book on the topic. A keen gardener, Dobbie had donated a large area of native bush to Whāngārei in 1910 which became known as Dobbie Park.
  

1922

• In his Naturalisation of Animals and Plants in New Zealand, George M. Thomson states that over 600 introduced species of plants have become established and acclimatised in New Zealand.
• The Forest Magazine of New Zealand is first published to promote forestry management.
  

1923

• The Native Bird Protection Society (later renamed the Royal Forest and Bird Society) is established to advocate "the efficient protection of our native birds...and unity of control of all wildlife".
• John Turbot develops the Turbot onion variety with outstanding storage qualities. Further breeding improves this onion which becomes known as the Pukekohe long keeper (PKL).
  

1924

• W.R.B. Oliver and H.Hamilton from the Dominion Museum are landed on the Poor Knights Islands where Oliver discovers the endemic Xeronema callistemon which becomes known as the Poor Knights lily; he publishes an account of the general vegetation in 1925 and a formal description of Xeronema callistemon in 1926.
• 20,444,000 rabbit skins are exported but their harmful impact upon vegetation continues unabated.
• Passion fruit (Passiflora spp) first commercially planted. Cultivation today is centered in the Bay of Islands.
  

1925

• Elsdon Best, a health inspector at Ruatoki in the Urewera District for almost 15 years, publishes his major work, Tūhoe: The Children of the Mist, documenting the customs, culture and uses of plants by this Māori tribe.

1926

• Department of Scientific and Industrial Research established.
• Cockayne's Monograph on New Zealand beech forests Part 1 (part 2 is released in 1928) covers Nothofagus species, hybridism and distribution. He notes overgrazing by deer is damaging regeneration.
• The Otari-Wilton's Bush in Wellington becomes the Open-Air Native Plant Museum and Leonard Cockayne directs its development until his death in 1934.
  

1927

• Massey Agricultural College is established in Palmerston North and opens the following year with a Department of Agricultural Botany; a Department of Horticulture is added in 1948.

1928

• W.R.B.Oliver is appointed director of the Dominion Museum in Wellington, a post he holds until 1947.
• Wheat Research Institute established as a Division of the Department of Scientific and Industrial Research (DSIR).
• Plant Research Station established at Palmerston North under the joint control of a committee made up of members from the DSIR, the Department of Agriculture and several other bodies. Harry H. Allan is appointed as systematic botanist to the Station. E.B. Levy's grasslands research team isolates a truly perennial ryegrass and two white clovers of high nitrogen fixing capability.
• The Winter Gardens in the Auckland Domain are completed consisting of cool and tropical conservatories, formal gardens and arbours. The next year the adjacent scoria quarry is converted into a fern dell.
  

1929

• Arthur's Pass National Park is the first national park to be created in the South Island. Consisting of 114, 394 ha this straddles the South Island main divide. Drier eastern slopes are covered by beech forest, which is complemented by podocarp/hardwood forest at lower elevations on the western side of the divide.
• New plantings of 57,000 acres of state forest and 42,000 acres of private forest are made with radiata pine.
• The Auckland Museum moves to the new buildings of the Auckland War Memorial Museum in the Auckland Domain. This includes a botanical library and an herbarium which today contains over 300,000 specimens including specimens collected by Joseph Banks, the Thomas Cheeseman collection and the Lindauer algae collection.
  

1930's-1940's

• Norman Elder accepts a teaching position in Havelock North and explores and botanises in the Ruahine, Kaweka and Kaimanawa Ranges in the central North Island, reporting on the vegetation and ecology and the impact of imported deer and possums.
• Burning of grassland, removing forest from slopes and overgrazing continues, resulting in a widespread loss of soil quality and an alarming increase in floods and soil slips.
• Work by the geneticists F.W. Hilgendorf and O. Frankel (within the Wheat Research Institute) results in the release of Cross Seven, a new variety of wheat that produces better grain for milling and bread-making.
• The Department of Internal Affairs begins extensive culling of red deer which will continue until the 1950s.
• 89 % of cultivated land is in grass and there are 29 million sheep.
• Largest remaining indigenous forests are in national parks on the South Island.
• Kauri timber production has fallen from 16 % to 2 % of all timber milled.
  

1930

• DSIR purchases an orchard at Appleby near Nelson and commences horticultural research.
• The Three Kings Islands 58 km northwest of Cape Reinga are declared a sanctuary. Goats, liberated in 1889, continue to devour much of the vegetation until exterminated in 1946.
  

1931

• New Zealand's worst recorded earthquake of the 20th century (magnitude 7.8) strikes at Hawke's Bay in the North Island, killing 256. This has a major impact on the landscape, damming rivers, causing major slips and fissures besides leveling the towns of Napier and Hastings.
• New Zealand Native Bird Society is the new name for The Native Bird Protection Society (founded in 1923). Two years later, the Bird Bulletin becomes The Forest and Bird which continues to be published.
• The Federated Mountain Clubs (FMC) is formed by 20 tramping, ski and alpine clubs, reflecting a shared concern for the future of New Zealand's mountain wilderness.
  

1932

• The Public Works Department begins using unemployed to stabilize coastal dunes planting marram grass, yellow tree lupin (Lupinus arboreus) pines (Pinus pinaster, P.radiata), macrocarpa (Cupressus macrocarpa) and eucalypts (Eucalyptus spp.). By 1951 extensive ‘sand forests' have been created of merchantable trees on land reclaimed from coastal dunes, mostly on the North Island.

1933

• The Royal Society of New Zealand Act changes the name of the New Zealand Institute to the Royal Society of New Zealand. The aim of the RSNZ is to represent scientists and foster scientific endeavour in New Zealand.
• Separate departments of botany and zoology are established at Auckland University College under headships of Mr T.L. Lancaster and Mr W.R. McGregor, respectively.
  

1934

• The Auckland Islands are gazetted as a Reserve for Preservation of Fauna and Flora. They consist of Auckland Island of 51,000 ha and Adams Island of 10,117 ha plus several smaller islands. The terrain is rugged with steep cliffs and some peaks over 600 m. There are 233 species of vascular plants of which 196 are indigenous and 6 are endemic. The islands also have the southernmost forest (rātā) as well as shrubland, tussock land and herbfields. Tree ferns also are at their southernmost limit here.
• The Native Plants Protection act is passed
  

1935

• 250,000 officially stamped possum skins are harvested

1936

• The Plant Research Station is transferred to DSIR, and renamed the Plant Research Bureau consisting of the Plant Diseases, Grasslands, Agronomy, Entomology, and Botany Divisions. The various Divisions are relocated (Plant Diseases to Auckland, Agronomy to Lincoln, Entomology to Nelson, Botany to Wellington) except for Grasslands, which stays in Palmerston North. Harry H. Allan is appointed director of the Botany Division and proceeds to establish it as a major centre for studies in economic botany (grasses and weeds).
• New Zealand Forest Products Ltd. Is formed.
• Agronomy Division of the Plant Research Bureau starts work on European linen flax (Linum usitatissimum) as a new crop for the South Island.
• Grazing lands on pumice soils of the central North Island are found to be seriously deficient in cobalt providing the key to unlocking this country to intensive pastoralism.
• The Botany of Auckland by Arnold Wall and Lucy M. Cranwell is published by the New Zealand Herald. A second edition is published in 1943.
  

1937

• Small commercial plantings of Chinese gooseberries (later named kiwifruit) prove successful in the Bay of Plenty. Hayward variety introduced.
• The Auckland Botanical Society is founded to advocate field work, publication, advocacy and the conservation and protection of New Zealand plants.
  

1938

• Lucy Moore appointed to the Botany Division of D.S.I.R, Wellington.
• District rabbit boards are set up to kill rabbits all year round and not just for food and skins. Rabbit numbers decline with a corresponding improvement in plant cover. Boards are disestablished in the 1980s.
• DSIR undertakes the task of protecting radiata pine timber against insect and fungus attack (which is perfected 15 years later with the momentary-dip boron diffusion process that makes possible the use of radiata pine for any part of a building not exposed to the weather).
• Tobacco Research Station established near Motueka.
• A Plant Chemistry Laboratory is formed as part of DSIR. (It becomes part of the Grasslands Division in 1951 and the Plant Chemistry Division in 1956.).
  

1939

• Wellington Botanical Society established, dedicated to research, field work, publication, advocacy and the conservation and protection of New Zealand plants.
• Ruth Mason joins the Botany Division, DSIR and in future years becomes active in assembling a seed collection, studying fibre quality of linen flax grown in South Canterbury and becomes an authority on plant anatomy.
• First commercial pulping of radiata pine, with the production of paperboard at Whakatane.
• Ruakura Agricultural Research Centre is established.
  

1940's

• Lucy Moore investigates New Zealand seaweeds as potential sources of agar, a gelling agent, formerly obtained from Japan. Several species of the red seaweed, Pterocladia, are found in sufficient quantities and techniques for gathering, drying and preparing agar are perfected.
• Professor W.R. McGregor of Auckland University leads a long and successful campaign to end logging within the Waipoua Kauri Forest.
• Guthrie-Smith dies in 1940, leaving 2,000 acres of his Hawke's Bay station in trust to the New Zealand public as an educational and recreational reserve.
• Omnivorous German wasps (Vespa germanica) arrive.
• The British government subsidizes the growing of European linen flax needed for the war. Grown and processed on the South Island in Canterbury, Otago and Southland, a total of 104,000 tons is sent to Britain between 1940-1944.
  

1941

• The Auckland Centennial Memorial Park Board begins unification and addition of tracts of land in the Waitakere Ranges west of Auckland for use as a recreational reserve. In the next 20 years over 7,000 ha of land is set aside.

1942

• Posthumous publication of Elsdon Best's Forest Lore of the Māori by the Polynesian Society in conjunction with the Dominion Museum. This includes a detailed review of the uses of native plants and plant products based upon his long acquaintance with the Tuhoe.
• Abel Tasman National Park consisting of 22,541 hectares of coastal land on Tasman Bay on the northern coast of the South Island is created culminating a long campaign by conservationist Pérrine Moncrieff. New Zealand's smallest national park, it consists of second growth beech and podocarp/hardwood forest, scrubland and exotic pines.
  

1943

• Davis Gelatine (NZ) Ltd in Christchurch commences production of agar. By 1949, 100 tons of dry seaweed are being processed each year. Davis ceases production in the mid 1970's.
  
  

1945

• Chair of Botany established at Auckland University College; Professor V.J. Chapman appointed. Chapman specializes in marine and fresh water plants, and together with Professor John Morton, is instrumental in founding the Marine Laboratory at Leigh.
• The Auckland Museum arranges for a scientific party to visit the Three Kings Islands and botanist Geoff Baylis discovers a single specimen tree subsequently named in his honour, Pennantia baylisiana (Pennantiaceae). The only known specimen of a vine with large tubular creamy flowers is also found and is later described as Tecomanthe speciosa (Bignoniaceae). Both endemic species have been successfully propagated.
• The insecticide DDT is introduced and in future years is quickly taken up by farmers finding it especially useful in controlling grass grub. (DDT is banned in 1970).
  

Late 1940's

• First national survey of possums shows that they have occupied about half of New Zealand.
• Eastwoodhill Arboretum now consists of 250 ha of mature trees and shrubs with over 4,000 different species and varieties from the northern hemisphere
  

1946

• The National Forest Survey (NFS) commences by the State Forest Service. This becomes a vast survey of New Zealand's indigenous forest for merchantable timber resources during which ecological data were collected (The Survey continued until 1955). Samples obtained during this survey form the beginning of a forestry herbarium.

1947

• Forest Experiment Station of the State Forest Service is established in Rotorua; this becomes the New Zealand Forest Research Institute in 1949.
• Harry H. Allan retires as director of the Botany Division of the DSIR and commences work on a new systematic treatise, 'The Flora of New Zealand'.
• The Ecology Division and the Fruit Research Division are established as part of the DSIR.
• DDT introduced in Taranaki to control grass grub. (DDT is banned in 1970)
  

1948

• The Royal New Zealand Air Force carries out trials of aerial seed sowing and topdressing in the Wairarapa). In the 1950s aerial topdressing of pastures becomes common, enabling new grass strains to be adopted. Trace element deficiencies (cobalt, selenium, copper, molybdenum and iodine) are now recognized in most soils.
• The Forest and Bird Protection Society is the new name for The New Zealand Native Bird Protection Society (1931). The objectives are to preserve and protect the indigenous flora, fauna and natural landscapes.
  

1949

• The Hop Research Station is established at Riwaka.
• Ruth Mason begins the first of about 15 expeditions throughout New Zealand to collect wetland species. Over two decades she collects and documents 13,500 specimens, clarifying the taxonomy of these plants.
• The Effects of the Australian Opossum on Indigenous Vegetation in New Zealand by Les Pracy and Ron Kean is published. This establishes that possum damage occurs where it is less detectable, at higher levels in the forest canopy and that deer browsing opens the forest making it more attractive to possums.