H.—34.
Mountain Soils. Soils of the steep and broken country over 3,500 ft. above sea-level are classed as mountain soils. They are unsuited to permanent agriculture. General Survey, South Island. Early in January the general soil survey of the South Island was commenced on the tussock lands of Canterbury which lie westward of the plains and downs, and which would not be suitable for work during the winter months. At the end of March, 1941, the soil types of the high-country portions of Tawera, Selwyn, Ashburton, Mackenzie, and Geraldine Counties had been identified and outlined. The soils may be divided into four main groups — (1) Recent Soils.—These comprise the recent river flats and consist mostly of infertile gravels, though some deeper phases are of moderate fertility. Small areas of peaty soils are included in this group : (2) Grey Soils.—These are developed on easy country from material derived from glaciers or glacial streams. They occur as hummocky moraines and terraces formed by streams issuing from the ancient ice-fronts in areas of moderate rainfall —i.e., 25 in. to 40 in. : (3) Yellow-brown Soils. —These are of similar origin to group (2) but developed under a higher rainfall—i.e., 40 in. to 140 in. They are much less fertile than the previous group : (4) Skeletal Soils. —These soils, which lie on steep slopes, occupy the greater part of the area examined, and are derived from greywackes and argillites. Three divisions of this group arc made : (a) Grey-brown soils which are light silt loams and sandy loams found in areas of rainfall between 25 in. and 50 in. ; (b) yellow-brown soils which are light silt loams found in areas of rainfall between 50 in. and 150 in. ; and (c) soils on the ranges flanking the Canterbury Plains, where the greywacke has been covered by a veneer of wind-blown loess. Soils of Waikato Lowlands East of Hamilton. On the accompanying map the main kinds of soil are shown. Some of the types recognized during the course of the survey occupy a small area and are not differentiated ; they will be separated on the detailed map which will be published later. Brown loams cover a fairly large area, mainly on the western portion of the area, and are similar in every respect to the brown loams found in the Waipa district. There is very little Ohaupo silt loam in the whole area, and what small patches there are, are very scattered. The brown-loam complex forms the hills on the extreme eastern margin and does not cover a very large area. A profile is : — (i in. to 7 in. dark-grey fine sandy loam. 2 in. to 3 in. light-brown free sandy loam. 12 in. light,-brown heavy sandy loam. On yellowish-brown very heavy clay. On the margin and steep faces of the soils of this complex are patches of Tauwhare silt loam. The Tauwhare soil is generally found on the lower foothills and steep faces of the complex. This type is sometimes found adjoining, and apparently covering in patches, the Hamilton clay loam. A profile is : — 3 in. to 4 in. black sandy ioam. 12 in. to 14 in. greyish to dirty creamy-yellow silt loam. On heavy, dirty creamy-yellow, fairly heavily iron-mottled silt loam. Brown granular clay —Hamilton clay —loam covers a large area on the eastern portion of the map. It is the same type as encountered in the Waipa area. The transition soils are extensive in area, and vary considerably in texture from fine sandy loam, with patches of pan, to heavy coarse sandy clay. This type is found generally on the eastern side of the area between the Hamilton-Cambridge Railway and the hills on the eastern margin. The meadow soils are similar to those found in the Waipa district, with the exception of the Eureka clay loam, which is found on the eastern part of the area. In texture Eureka soil is much heavier than the usual meadow soils, and in the northern portion heavy iron pans exist at a depth of from 18 in. to 24 in. A profile is : — R in. dirty brown clay loam (sometimes reddish) with patches of creamy-grey clay loam. 12 in. creamy-white heavily mottled clay. 4 in. to 6 in. yellowish very heavy, sticky sandy loam. 2 in. to 5 in. dark-brown iron pan. On yellowish clay (shingle at from 3 ft. 0 in. to 4 ft.). The j.>eat soils are common in this district, and cover practically the whole of the northern portion. There are also a few small patches scattered throughout the area mainly adjacent to the hills, They include peat, peaty loam, and peaty sands and silts. The area of deep peat is comparatively small and occurs near the Hamilton-Morrinsville Railway. The drainage of much of the land occupied by meadow and peat soils needs to be improved.
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