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Rotokauri Clay Loam and Peaty Clay Loam. —The ground covered with Rotokauri clay loam is of comparatively small extent. These soils occur in small swampy arms extending into the rolling hills and on the margins of peaty swamps. The profile is 3 in.-6 in. dark clay loam or peaty clay loam with a crumb structure on sticky translucent grey clay. These soils are probably derived mainly from the fine textured portion of the volcanic ash covering the Hamilton hills. Waipa Sands and Loams. —The Waipa sands and loams cover the low terraces of the Waipa River and receive fresh deposits during strong floods. The sands which form a narrow strip close to the river are generally coarse. The loams occupy those parts of the terraces lying farther back from the river and cover a much greater area. Both of these soils are brown in colour and probably have a low nitrogen content. Except for a narrow badly-drained strip at the back of the terraces, they are generally well farmed. Waikato Sands. —The Waikato sands cover the hummocky terraces bordering the Waikato River. They are not subject to present-day floods. The sands being coarse —to 3 ft. or more below the surface —dry out badly in summer. These soils are brown in colour and probably have a low nitrogen content. Generally the pastures on this soil are poor. Maori Gravelly Sands. —On the flats covered with the Horotiu sandy loam the Maoris, before the arrival of the pakeha, dug conical holes up to 15 ft. deep to obtain a gravelly sand which they spread over the land to a depth of 9 in. or 10 in. To build up the store of lime, potash, and phosphate in this new soil the Maoris probably burnt manuka on it. These Maori soils occur chiefly near the Waikato River between Ngaruawahia and Hamilton. At Ngaruawahia there is a continuous area of about two hundred acres of Maori gravelly sand. Small patches occur near the Waipa River. These man-made soils, which were used for growing the kumara, are similar to those in Waimea West described by Rigg and Bruce. The Maori gravelly sands are dark brown to black in colour and support a good sward of grass—much better than is to be expected on a soil of such a coarse texture. PUKETOTARA BLOCK, BAY OF ISLANDS. (By L. I. Geanqe.) Towards the end of May the writer spent a week in the Bay of Islands, at the request of the Department of Native Affairs, examining the soils on the Puketotara Block, which lies about eight miles west of Kerikeri. The block, containing 2,196 acres, is part of a dissected plateau at between 600 ft. and 850 ft. above sea-level. Kerikeri River, on the north boundary, is entrenched fully 500 ft., and Maungaparerua Stream, on the south, is at most 300 ft. below the plateau. Most of the block consists of flat and rolling land covered with scrub—manuka, fern, hakia, and kumarahou. There are two types of soil—Kerikeri clay and Kaeo clay : Kerikeri clays, occupying much the larger area, are derived from basalt, whereas the Kaeo clays are derived from fine-grained marine sediments. The profile on the Kerikeri clay is— 9 in.-11 in. dark-brown clay with occasional iron nodules, 3 in. dark-brown clay containing many iron nodules, 3 in. dark-brown clay with occasional iron nodules, on light-brown clay. This is a podsol profile. There has been much downward leaching of the fertility elements. In places the nodule layer is on the surface ; the dark-brown clays which formerly overlay it have been washed away. Similar soil profiles are found at Pungaere, Waipapa, and Okaihau. The profile on the Kaeo clay is— 10 in. dark-grey compact clay on light-grey clay. This soil is a podsol and is considered to be similar to the gum-land soils of North Auckland. Pastures established by farmers in the neighbouring districts on the Kerikeri clays are satisfactory only when heavy applications of fertilizers are made. A farmer who used 3 cwt. of basic slag when laying down his pasture and did no subsequent top-dressing has an extremely poor cover. Good results have been obtained by an Okaihau farmer by an initial application of 1 ton of ground limestone and 3 cwt. of superphosphate and 2 cwt. of superphosphate each succeeding year. Heavy liming is essential, for the aluminium and iron-compounds of the Kerikeri clays, in the absence of lime, would render the phosphates unavailable to the plants. The Kaeo clays, if correctly correlated with the gum-land soils, do not need heavy applications of lime. From the experiments made by the Department of Agriculture in the gum-land soil at Puwera, near Whangarei, it was found that the soil needed an initial application of 7 cwt. of a mixture of basic slag and super and 3 cwt. of this mixture in succeeding years.

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