Soils of Chatham Island (Rekohu) Fronlis icce: 11nproved pastures Tiki larolin phase, on clay, strongly rollink near uitand tminshil’ NEW ZEALAND DEPARTMENT OF SCIENTIFIC AND INDUSTRIAL RESEARCH N. H. TAYLOR Director SOIL BUREAU BULLETIN 19 SOILS OF CHATHAM ISLAND (REKOHU) By A. C. S. WRIGHT Soil Bureau 1959 Price: Paper cover, 15s. Quarter cloth, 20s. N.g. Soil Bur. Bull. 19. 60 pp. 22 figs, 5 tables R. E. OWEN. GOVERNMENT PRINTER. WELLINCTON. NEW ZEALAND -lm CONTENTS Page Introduction 7 .. .. Soils 10 The Pattern of the .. .. 16 Factors Concerned in Development of the Soil Pattern the .. 16 Geology .. 20 Climate .. 22 Flora Fauna and .. .. Soil Pattern 29 Historical Factors Causing Modification of the .. .. Pedological Significance of Soil Pattern 31 the .. .. Agricultural Significance of Soil Pattern 32 the . Elsewhere 34 Relationships with Soils of New Zealand Mainland and the . 36 Development Potential of Soils the .. Acknowledgments 38 .. Appendix 39 . .. 39 Description of Soil Types and Their Plant Nutrient Status . Soil Chemistry (by R. B. Miller and L. C. Blakemore) 54 . .. References 58 . .. 60 Index Soils to . .. Map (in pocket) Extended Legend (in pocket) INTRODUCTION grouped Chatham under Lieutenant Chatham ishind is the largest of la islands the armed tender forty-fourth parallel latitude in William Broughton voyaging independently to about the of south longitude 17fic It lies rendezvous with Captain George Lancouver at the vicinity of west. at about South Tahiti, group; landing was made on ann miles east of Lyttleton in the Island of sighted the a The island itself New Zealand (fig 1). the main island (Vancouver 1798). islands in Chatham formally Chatham Island and in due There are three main the was named group Admiralty group: Chatham (formerly given the alternative course the appeared on charts There least names of liekobu and Wharekauri) of 224,000 acres, under the same name. are at three other in Pacific* Pitt (Rangiauria), of 15,000 acres, and South-East islands of the same name the and the Island (Itangatira) of about 640 acres. The remain- adoption of one or other of the Polynesian names for island be is not ing islands are much smaller, some little more than the main might a suggestion that between rock pinnacles. Only Chatham and Pitt are occupied without merit. To avoid confusion things group permanently, although sheep are still grazed on the pertaining to the as a natural unit, and things island, in small outlying islet of Alangere. pertaining specifically to the main this be Chatham report the former will referred to as islands or Chathams and the latter as Chatham n island. The approach from the north, or.from the east, or from the north-west raises a low and somewhat double -- uninspiring landfall whose chief feature is a From rank of isolated conical bills. the south the a land mass emerges with an almost smooth outline, proves be which on closer inspection to the summit point of a forbidding line of high cliffs. The highest island, Oropuke ft), behind on the (938 stands close barrier but even here, as elsewhere on this of cliffs island, landscape is of subdued relief. the the gentle predominate: Throughout the island, slopes is flat less 940 of the topography to rolling, and than 20 consists of steepland (fig. 2). Island is like 0 Outhne, Chatham shaped a ALAN broad Maori anchor-stone: narrow in the waist and at either end. It has a total area of approximately 224,000 acres, but no less than 49,300 acres (22’’,) is by lakes lagoons and I2,900 acres - occupied and dune (Gof,) consists of unstable beach and sand. The stable land surface comprises some 161,800 island. acres, only 720,, of the area of the -r - -- geography A brief general account of the of the ------ .o Chatham group has been given by Falla (1950) and oo , more detailed information on various aspects of be found in agriculture, forestry, and wildlife can a I ig. 1. location of Chadunn Islands in relation to No\\ Zealand *Chatlunn Island in the Manallanes region of southern The Chatham island . lur name 15 CommonlY used Chile (lat. $(P 40’ S; long. 74’ 20’ W). group being Chatham island in Marshall archipelago. the largest island in the in addition to the Central I i whole group. It commem- the name applied to the al-ejl a lectorSR.Cir sland) in is et. tol it the orates the OCCasion \then, in the summer of 1791. (hilapagos group (Int, I 0’ S; long. 80* 34’ W). number of New Zealand Government unpublished During past population the century the of the departmental in particular Madden reports, those of Chathams has fluctuated between 400 and 700. (1952), Patterson (1951), Connell (1938), Barron Today, with about 500 people, the population is (1952), Howse (1953). These and reports clearly 150 fewer than in 1861, and there is a very high show development proportion that of the natural resources of (nearly 500/o) under the age of 20. The islands has lagged far behind of the that the rest of number of adults on the islands is less than 300 and, New Zealand. apart from about 40 temporary residents living The Chatham Islands part Dominion are of the mainly in Waitangi township, they are mainly New Zealand. They have of the status of a county, sheep farmers living on about 90 farms scattered islanders and the are empowered to elect a county throughout Chatham Island and on one or two The Government is council. senior representative a farms on Pitt Island. The annual report of the from commissioner appointed the staff of the Department of Island Territories for 1951 shows Department of Island Territories. The islanders livestock that the maintained on farms in the have had parliamentary group representation since 1922, consisted of 127,000 sheep, 5,000 cattle, and in as voters either of the mainland electorates of 400 horses. Freight charges on produce shipped to Lyttleton (for Europeans) Western Maori or (for the mainland are high, and if the passage is a rough Maoris). one livestock may lose condition markedly before 176 45’ 176630’ 176ois’ E FLAT TO ROLLING MS MOD. STEEP TO STEEP M STEEP TO VERY STEEP :i :::: 176 45 176015’ 176 30 Fig. 2. Land slope map of Chatham Island 8 In year industries, so islanders can con- reaching the saleyards. an average the that the themselves development in farmers on the Chathams send over to the mainland tribute more tolvarcls the cost of the This fmancial or some 3,000 bales of wool, 20,000 head of sheep, and islands. might require considerable be given 250 head of cattle. Under existing conditions on other assistance, but before this can the Chathams, farming pays quite but profits resources of the island require to be sur- the well natural from potential for further development are modest in comparison with those similar veyed and their classes of land on the mainland. estimated. The reconnaissance soil survey of 1985 was one The problem of of communication with the rest purpose of these surveys. The was to map the New Zealand has never been satisfactorily solved, mam soil types and, by establishmg correlations fhe farming industry is, as yet, too small to support with. similar. soils. on the mainland whose farming fully or to subsidise. a regular shipping service, and potentialities. are well known, achieve some esti- is for several months in the winter there no surface potential . mate of the development in respect of communication with the mainland, apart from an industries. dependent upon the soil. It was designed occasional fishmg. boat. Landing. facilities. for air- be a rapid. stocktakmg. and correlation. survey of yet developed permit to craft are not adequately to group. bad the soil. resources of the Unfortunately, Roading, scheduled services. the chief means of Island; weather restricted the survey to Chatham internal communication, is but poorly developed Pitt Island was not visited.. and at some seasons between distant farms travel This bulletin opens with a general account of the is exceedmgly. As with. so many other still tedious. in pattern chief components the soil. and their poor is isolated communities, access accepted as a proceeds relationships. to mainland soils,. and then normal feature of island life and people are harden- a description. of the various factors in the island. Many okler mhabit-. to ed to these conditions. of the pattern. environment mainly. responsible. for the soil. by, do not reahse. ants are not overconcerned or following deals ’ This. section. and one, which by Chatham the the limitations. imposed the way of briefly. with. history of land use in Chathams, particularly younger the the life. Many others, . amongst the go bring out a number of important points that generation and amongst recent settlers, wish. most far towards explaining. the present state of agri- see conditions. on . brought earnestly to the island provide . be import- culture and also leads that will nearer those pertaining in rural districts on the . future land development is in- ant in the when mamland.. Progress towards a more satisfactory . tensified. More detailed Information about Individ- way of life is undoubtedly being made, but the rate nal types of soil. and related matters, which will of progress is hampered considerably. by lack of probably be of less interest to general readers, is money for development projects. provided. m. an appenchx.. .This. appendix. includes Local rates collected by the county council are detailed descriptions of the main soil types with payable plant raised indirectly by a surcharge on all notes on their nutrient status and an estimate individual potential for or goods entering or leaving the island by the steam- of their agricultural development.