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of iron oxide occur throughout the profile a definite layer of ironstone nodules is nowhere developed. On the shallower phases, however, a layer of alumina nodules is developed. Many good citrus orchards are now established on this soil. (c) The Ngapuhi clay covers 1,900 acres of fiattish to gently rolling country near Ngapuhi Kailwaystation. A typical profile is : — 6 in.-8 in. dark-brown clay ; 22 in. brown compact clay with alumina concretions ; On reddish-brown compact clay with alumina plates and fragments of decomposed basalt. This land was formerly covered with good mixed bush containing taraire, puriri, kohekohe, totara, &c. It is capable of carrying good pasture, but much of it is at present poorly farmed. (d) The Waimate clay, which covers about 3,000 acres close to Waimate North, has developed on the rolling surface of the older basalts under a cover of mixed bush containing a large proportion of puriri and taraire. It is a deep, friable, well-drained clay similar to Kerikeri clay, but of more reddishbrown in colour. Nodules are rarely developed, and the soil is naturally more fertile than the Kerikeri soil. Dairying and sheep-farming are carried out on this soil. (e) The Te Puke soils are deep-reddish clays and loams covering the scoria cones and mounds. They occupy only a relatively small area. (/) The Kaikohe clay loam covers the flats (4,800 acres) near Kaikohe. It is developed from the younger basalt-flows and is more fertile than the Kerikeri, Waimate, and Ngapuhi soils. The topsoil is a brown, free, crumbly clay loam ; the subsoil is duller brown and more compact. The area is used for dairying. (g) The Ohaeawai silt loam and building silt loam are derived from basalt-flows younger than those that give rise to the Kaikohe soils. They are shallow soils, with a free, fine powdery structure, and are comparatively rich in plant-foods. They are used for dairying and sheep-farming. (4) Transition Soils. —The soils of this division show the transition between the red-brown soils and the podsols. They are developed from basic igneous rocks, most of them under the poorer types of mixed forest and the more mature soils under kauri forest. They occur typically in Awarua Valley and on the Tutamoe Plateau. The topsoils are usually grey-brown crumbly clays ; the subsoils are compact sticky clays, generally brown in colour but grading into a flecked greenish-brown in the more mature soils. In some places a grey leached layer exists below the topsoil, but the single grain structure of the true podsol is not developed. These soils are extremely acid and deficient in plant-foods. On areas recently covered with forest the ashes from the bush burns improve the soil for a few years, but the open scrubland from which the forest has long disappeared needs heavy dressings of lime with phosphate for good pasture establishment. Tentatively included in this division are the reddish-brown and brown clay soils covering the steep country surrounding the Tutamoe Plateau. On account of soil-erosion these soils are less mature and more fertile than the other soils of the division. They are used for sheep and cattle grazing. Fertilizers. It is evident that in order to farm the district efficiently much larger amounts of fertilizers should be used. The chief need is for lime and phosphates. A comparison between the responses shown on the pasture top-dressing trial plots of the Department of Agriculture and the profiles of soils in various places suggests the following correlation : With podsols and podsolized soils the need for lime becomes more evident as the profile becomes more mature. Only skeletal and slightly podsolized soils respond well to phosphate alone. Where the podsols are so mature that the clay is well leached from the topsoil, potash responses appear, and increase with the maturity of the soil. A similar correlation appears to exist with the red-brown soils, but basic phosphates or mixtures of lime and superphosphate seem superior to superphosphate even on the young soils, and responses to potash are to be expected on all the soils of this division when applied in conjunction with lime and phosphates. Land-settlement. The unoccupied lands of North Auckland have often been commented upon, and, indeed, the possibility of settling easy rolling country in a climate which gives such a long growing period is worthy of attention. It must be remembered, however, that most of the unoccupied lands are problem soils, and for this reason attempts at settlement should be preceded by carefully controlled experiment, and the settlement itself should be carefully planned and supervised until success is assured. Many pitfalls await the uninitiated. THE KERIKERI CITRUS AREA. (By N. H. Taylok.) During the past few years it has been definitely established that citrus fruits, particularly sweet oranges, can be successfully grown at Kerikeri, North Auckland. The oranges compare very favourably with imported varieties, and it seemed reasonable that some effort should be made to supply our own needs during at least a part of the year.

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