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Soils from Resorted Material. The soils derived from resorted material have been divided into seven types grouped into five series. The Hangatahua Series, which has been mapped over 18,500 acres, includes all the soils formed from volcanic material resorted by the streams draining from Mount Egmont. This series is subdivided into loams, bouldery loams, sands, and gravelly sands. In general, the sands and gravelly sands lie close to the banks of the streams. The loams which lie behind the sands and farther from the streams are at a lower level than the sands and are in most places swampy. The sands near the coast—e.g., near the mouth of Hangatahua Stream—dry out badly during summer. The bouldery loams are mainly unfitted for agriculture. The swampy loams are at present but little utilized. The Glenn Series is related to the Hangatahua Series in that the parent material is volcanic debris brought down by the streams. This series is classified separately because 1 ft. or 2 ft. below the surface there is, in many places, a well-developed iron and humus pan up to 18 in. thick. Glenn loam, which has been mapped over 13,500 acres, extends from Kaponga to within two miles of Otakeho. The soil is poorly drained and in its natural state supports swamp vegetation. The soils of the Waitara Series are derived partly from resorted volcanic debris and partly from material washed from the calcareous mudstones of the eastern upland. Waitara sand and sandy loam have been mapped over 1,500 acres on terraces bordering the Waitara River. The Eltham Series includes the soils formed from a mixture of peat and volcanic ash, which cover the swamps lying east of the railway-line between Eltham and Inglewood. Eltham peaty loam covers 8,000 acres, the largest areas being the swamps of Ngaire (4,000 acres) and Eltham (3,000 acres). Where properly drained the peaty loams carry a fairly good pasture. In some places the soil is " waterproof " owing to the presence of wax. The soils of the Patea Series are those derived from wind-blown sands. Patea sand has been mapped over 6,500 acres. It occurs on narrow strips, seldom more than a mile wide, bordering the sea-shore. FIELD-WORK ON SOILS OF WAIPA COUNTY. (By L. I. Grange and N. H. Taylor.) Topography. Waipa County lies between the Waikato River and its main tributary, the Waipa, and extends from Te Awamutu in the south to the junction of the two rivers at Ngaruawahia. Throughout, the country is easy, wide flats predominating in the north and rolling hills in the south. The flats are approximately 150 ft. above sea-level; the rolling hills rise approximately 300 ft. Many swamps occur throughout the country, the largest being Rukuhia, which lies close south of Hamilton. Geology. The geology of the Waipa County is described in Bulletin No. 28 of the New Zealand Geological Survey, and this has proved a valuable aid in the mapping of the soils. In Pliocene times rivers, draining from the rhyolite-covered hills in the south, filled the Hamilton Basin with beds of rhyolite sands and gravels. The region was then uplifted, and after these sandy beds had been eroded into rolling hills and valleys volcanic eruptions covered the countryside with 10 ft.—ls ft. of ash. Later the Waikato River, issuing from the Maungatautari Gorge, built a gently sloping alluvial fan across the rolling lowlands, filling in the valleys and leaving only the upper parts of the ash-covered hills projecting. The different courses which the river took across the plain are marked by long low ridges of sand and gravel, which in many places form barriers across the mouths of the subsidiary valleys damming back the streams and forming lakes and swamps. Away from the sandy ridges, mud and clay were deposited over wide flats, and as the building-up continued the lower-lying parts were converted into extensive swamps. On the west the Waipa River also built up its bed, keeping pace with the Waikato, but as it flowed more slowly the debris it deposited was finer in texture. At the close of the fan-building stage the rivers entrenched themselves in the easily-eroded alluvium, leaving their banks bordered with long, narrow terraces. Soils. In the area so far examined thirteen soil types have been recognized, and these are tentatively classified as follows : —

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Parent. Material. Soil Type. Soils of the rolling hills .. Subaerial volcanic ash, Hamilton Shower .. Hamilton clay loam. f f Horotiu sandy loam and sand. I Te Kowhai sandy loam and Water-sorted rhyolite ash .. .. clay loam, &c. | Te Kowhai sand. Soils of the Waikato Fan <, I Te Kowhai sandy clay. Decaying swamp vegetation .. .. .. Rukuhia peat. Decaying swamp vegetation and water-sorted / Rukuhia peaty silt and sand. rhyolite ash \ Rukuhia peaty clay. Water-sorted Hamilton ash .. .. .. Rotokauri clay loam. Soils of the Waikato Terraces .. Water-sorted rhyolite ash .. .. .. Waikato sands. Soils of the Waipa Terraces .. Water-sorted rhyolite ash mixed with alluvium/ Waipa sand. from greywacke and mudstone \ Waipa loam. Maori soils .. .. .. .. Maori gravelly loam.