Mineral Content of Pastures. Lime Deficiency in King Country Soils, and the Effect on Plant and Animal.

Transactions and Proceedings of the Royal Society of New Zealand, Volume 59, 1928, Page 406

Mineral Content of Pastures. Lime Deficiency in King Country Soils, and the Effect on Plant and Animal. By B. C. Aston, F.N.Z. Inst. [Received toy Editor, 30th July, 1928; issued separately, 31st August, 1928.] Iron-starvation (“bush-sickness”) in ruminant stock occurs in its typical form when the animals are grazed on pasture grown on the coarse air-deposited rhyolitic pumice soils, particularly the sandy-silts and gravelly-sandy types, of the North Island volcanic plateau. Lying to the westward of this great area which may be measured by millions of acres, there are extensive areas of finer air-deposited soils belonging to the loamy types, derived from showers of mud or dust or similar fine-grained volcanic material which has been deposited on the soils derived from a limestone, rhyolite, or greywacke country rock which underlies them. This fine deposit weathers down to a fertile loam, and its section in the road cuttings presents a characteristic appearance—a brown loamy face which cracks up in summer appearing as a much fissured surface. This deposit is no doubt what Henderson and Ongley (1923) refer to in their Bulletin of the Geological Survey (No. 24 Geology of the Mokau Subdivision, p. 56) under the heading “Rhyolitic Rocks.” The authors say: “Westward only the finest dust seems to have been “deposited. This has been to a great extent eroded and what remains “has been decomposed to a brown sandy loam of characteristic “appearance. Its distribution is not shown on the maps, but it “covers the hills and some of the valley bottoms over a wide area “and must at one time have covered the whole region. It may be “observed in the Mokau Valley west of Pio Pio, at many points on “the hills between the Mangaotaki and the Awakino rivers, and again “on the Taumataemaire Hill.” The area in which it is thought that a mineral-deficiency disease hitherto unrecognized occurs, is situated in the Mairoa and adjacent ridings of the Waitomo County. The situation of this area is generally about 1,000 ft. above sea-level, the rainfall being a heavy, well-distributed one. In August 1926 the writer was first consulted regarding a type of soil occuring about 15 miles west of Te Kuiti. The first enquiry related to the soil itself which had ceased to produce the same good quality of sheep-pasture that in the past had given this district an excellent name as a fertile country in the years immediately following the “burn”—the operation of “bringing in” the bush-country, or in other words of quickly converting forest-land to a sheep and cattle-grazing pasture. It appeared upon investigation that land for which £17 an acre was refused previous to the war was now unsaleable even at one-third of that price, and that some farms had changed

hands at something like £2 an acre, a price which included dwelling and other buildings and all other improvements. Such rapid and great deterioration in the market-value could not be for the greater part attributed to falling prices. The forest which originally covered this land was tawa (Beil-schmiedia Tawa), rimu (Dacrydium cupressinum), rata (Metrosideros robusta), pukatea (Laurelia novae-zealandiae) while the undergrowth was fuchsia (Fuchsia excorticata), whiteywood (Melicytus raimiflorus), supplejack (Rhipogonum scandens), ribbonwood (Hoheria), fivefinger (Nothopanax laetum and N. arboreum), rewarewa (Knightia), mangeo (Litsaea), Freycinetia and similar shrubs; a type of primeval vegetation which usually indicates good soil rather than bad. The history of this settlement as given to the writer relates that for the first seven or eight years after the burn the pasture carried 1½ ewes to the acre and the lambs did well on it, but after this the pasture deteriorated very rapidly; the so-called English good grasses disappeared, and the carrying capacity fell below one dry sheep to the acre, and even with this diminished stocking the animals did not thrive. The extraordinary thing was that the usual remedy for deteriorated land, viz., top-dressing with phosphates, although it improved the summer carrying capacity did not effect the improvement hoped for in the returns. The pasture on land that had been top-dressed with basic slag, superphosphate, and potash manures (8 cwt. in four years) was still apparently deficient in some ingredient. In summer the top-dressed pasture looked well and grew a lot of good grass, but in winter the ground became full of moss which disappeared in the summer. The number of culls in the flock was unusually high, although when these were taken to land where no deterioration had set in they fattened and often became the best sheep in their new home. The topography generally is that of what would be called “easy country,” and the whole is well watered by streams and creeks. A few samples of soil had been received and a composite sample made up for analysis showed that the soil was essentially a loam. Each sample (W 506-514) was tested for “lime-requirement” and gave results varying from 1.15 to 0.67 per cent, calcium carbonate required calculated on the water-free soil. Where, however, a sample (No. W 508) was taken quite close to the limestone outcrops the “requirement” was only 0.4 per cent. The chemical analysis of the composite soil W 609 showed no deficiency of any of the three valuable ingredients of fertilisers, the available potash being very high, and phosphoric acid being high, while the total nitrogen was particularly high. The writer visited the locality for the first time in November 1926, and was struck with the poor condition of the sheep, which could not be explained by the lack of pasture. Some deficiency of the mineral food was suspected, especially as on examination the bones of sheep which had died were found to be unusually fragile and light. An alternative theory held by some was that internal parasites were the cause of the poor condition. On obtaining the highest veterinary advice and on post mortem examination of sheep in September 1927 and subsequent dates it was found that the parasites present were not suffi-

ciently numerous to account for the condition, and the hypothesis of a deficiency-disease was adopted as the cause of the trouble. The analysis of the soil not revealing any deficiency of nitrogen, available phosphoric acid, or potash, and the application of the two latter manurial ingredients to the soil failing to mitigate the deficency-diséase, it was necessary to look for the deficient element or elements among those which are in normal soils present in quantity sufficient for the growth of plants and which are not generally required to be provided for plant-food in artificial manures. In this selection one was guided by several facts; but the chief were that the bones of the animals were undoubtedly affected, and hence one of the elements forming bone would be probably the one sought for, and the other fact was the high lime-requirement of the soil, which was in the neighbourhood of 1 per cent, whereas the usual figures for North Island soils are from 0.2 to 0.4 per cent, of calcium carbonate. Other analytical data pointed to excessive soil-sourness and higher organic-matter content than normal soils show. The soil-sourness was determined to be extreme by three analytical tests, viz., the lime-requirement figure (Hutchinson and McLennan's method), the hydrogen-ion concentration (pH) figure, and the replaceable calcium figure, all of which testify to an abnormal soil condition, the remedy for which would be to apply lime. According to Russell “Humum is more sensitive than clay to changes in calcium content and more rapidly becomes neutral on the addition of excessive doses of lime, or conversely more rapidly developes acidity as the lime is washed out.” The analysis of this soil shows an excessively high organic-matter content. It will be interesting to consider what takes place in the soil when a forested country is felled and burnt. The most important chemical effect will result from the distribution over the surface of the land of a dressing of ashes containing carbonate of lime in an infinitely divided state, together with some phosphate and potash. Calcium is the chief element in wood-ashes, potassium being present to a much less extent. The good result accruing from wood-ashes is often attributed to the potash contained in them when the result is more likely due to the lime. There is nothing in the analysis of these soils to show that potash is deficient in them, though the potash fallacy led one farmer to use potash fertilizers on this type of country; but he obtained no evidence of any improvement from potash. According to data kindly supplied by the Director of Forestry (Mr, E. Phillips-Turner) a burn of forest of the tawa-rimu type might be expected to deposit on the surface of the land from ½ ton to 2 tons of wood-ash per acre, which may be considered a very moderate estimate. Anything like ½ ton to 1 ton of pure fine carbonate of lime per acre on hill land is a dressing not to be despised. There is considerable evidence as to the elements which are washed out of clay soils from the experience at Rothamstod Experimental Station. These show that potash and phosphate are not leached out of the soil in any considerable quantity, whereas calcium is washed out in very large amounts. Hall, “The Soil,” p. 212

states that “phosphoric acid and potash applied as manures are fixed by the soil whereas the metals sodium and calcium are only slightly if at all retained. These results are confirmed by the analysis of the water which flows from the land drains under normal conditions. This will generally be found to contain nitrates (and sometimes in fair quantity) sulphates and chlorides of calcium and sodium and considerable amounts of calcium bicarbonate but rarely shows more than a trace of ammonia, phosphoric acid and potash.” One may say that the rainfall of this area is heavy and well distributed, so that if we knew of the rapid leaching out of some element necessary to fertility which was present in the soil after the bush burn and then gradually leached out this would be another link in the evidence. That such an element is calcium who can doubt? In the finely-divided condition in which it exists in wood-ashes, whether present as quick lime, slaked lime, or carbonate of lime it would be quickly available and have a greatly ameliorating influence for the first few years and then be leached away or rendered unavailable, the pasture becoming progressively poorer in legumes and the better grasses. Deficient calcium in the pasture leads to disease in stock. It also probably injuriously affects the growth of bone in the animal, it being the principal constituent in bone-ash. Deficient calcium in this soil would account for the absence of clovers, the component of pastures which supply large quantities of calcium in the feed. Neither nitrates, sulphates, nor chlorides are likely to be so deficient as to cause the malnutrition. That deficient calcium in the soil is reflected in the composition of the grasses growing upon it, and is shown by the analysis of grasses growing near the limestone outcrop and sample growing far away from the influence of lime. The latter are always poorer in calcium than the former. In the pasture of a typically deteriorated farm that has never had any top-dressing since the burn, one hears that it originally carried rye-grass and clovers, and finds now only Danthonia, brown-top, and yorkshire-fog, with traces only of the nutritious Leguminosae, Lotus major being the only species visible. That this absence of Leguminosae is a fact and not a cursory impression may be accepted when it is recorded that a skilled assistant, who was sent up in April 1927 to obtain a sample of red or white clover on a 800 acre farm much of which had been top-dressed with phosphates and potash, had to return with the report that he could not even obtain enough to analyze! A pound of the sample would have been ample. It was also reported that swedes and turnips would not thrive unless the soil was limed; and club-root and finger-and-toe in cruciferous plants, grown in either field or garden, was alleged. The pasture was full of moss. Upon pasture that had been limed the sheep were always found grazing. Subsequently it was reported that the very sheep which had been diagnozed as suffering from a deficiency-disease in September 1927, when placed on a limed paddock fattened and were sold fat in a few months. On the other hand, sheep grazed on land which had been liberally top-dressed with phosphates and

potash salts, although the pasture seemed of better quality and of increased carrying capacity, did not respond as they did on the limed paddock. A growing hogget requires .0093 lb. calcium oxide a day (Wilson). 100 lbs. of the dry matter of the worst Mairoa pasture contains, say, 0.7 lb. CaO. A hogget eats less than 3 lbs. dry-matter a day, or say .021 lb. CaO but can only assimilate one-third to one-half of the mineral matter ingested, hence a figure is arrived at which approaches .009 lb. more or less for summer conditions. In winter the CaO content of the pasture is sure to be lowered and the amount of Ca will fall below the theoretical requirement of .009 lb. per day. The case of a milking ewe is far worse. She requires .020 lb. CaO daily and if her ingested food only contains .021 lb. there is no margin to allow for calcium not assimilable. Sheep require more lime than cattle in their proportion to the P2O5, for while sheep require 1: 1 ratio, cattle require 1 P2O5 to .85 CaO. The fact that in the aggregate large quantities of phospate had been applied to the land without improving the average quality of the pasture throughout the year sufficiently to enable the flock to develop normally is vouched for by two farmers who had tried that method. That large quantities of phosphate have been applied is indicated by the high phosphate content of the manured land; apart from this one finds that the unmanured land is for hill-pasture country well supplied with available phosphate and particularly well supplied with potash (see analysis of sample W882). In one case the soil was analyzed by taking successive three-inch cores and analyzing the first, second, and third three inches separately, instead of the usual practice of taking one core of 9 inches. This was done in the case of unmanured land on two separate farms. The results, show that the soil is well supplied for a hill-soil with available phosphate and potash while the lime-requirement figure is still exceptionally high for all depths (see samples X284-289). The writer reported on 9th December, 1926, “From what I could see and ascertain from laboratory tests it seems that lime is required to improve the composition and texture of the soil, the lime absorption of most of the soils being about one per cent. which translated into terms of tons per acre would roughly speaking amount to about ten tons per acre of carbonate of lime. This is, of course, an empirical laboratory test and by no means to be taken as indicating that it would be profitable to apply such a large amount. It is extremely desirable that further investigations should be made into the best method of reclaiming this fine country which is rapidly going back to fern. It seems quite probable that some form of calcium which is alkaline may prove a very strong agent in bringing this land back to its previous productive capacity.” The fact that the lime-requirement figure shows an absorption of calcium carbonate approximately equal to ten tons per acre of ground limestone has been advanced as a reason for abandoning the Mairoa lands, since no one could afford to apply this quantity of lime. It is not, however, necessary to satisfy the high lime-require-

ment of ten tons per acre; in fact, the full lime-requirement never is satisfied even when, as in the majority of North Island soils, it is only in the vicinity of two to four tons per acre. There are several methods which might be tried with the object of avoiding the great expense of liming large tracts of hill-country. These fall under different headings:— (1.) Cheapening of lime— (a) By having local grinding-plants for reducing limestone to powder. (b) By having local kilns for burning limestone.1 (c) By giving a subsidy to farmers who cannot take advantage of the free railage because there is no railway. Thus 100 miles free railage is 8/5d. per ton for lime and ground limestone. (2.) Feeding pellets or licks containing calcium in some available form. (3.) Bringing up the calcium content of the pasture on one paddock on each farm and running the entire stock periodically through that particular paddock. Statement Of Lime-Requirement. Per Cent. Carbonate of Lime. On air-dried soil On moisture-free soil W/506 Home paddock, Mairoa 1.06 1.15 top-dressed for 4 years. 507 " " 1.08 1.22 top-dressed for 3 years. 508 " " 0.35 0.40 close to limestone rock. 509 Oldest clearing " 0.66 0.77 top-dressed for 2 years. 510 " " 0.81 0.87 top-dressed for 2 years. 511 Subsoil of 512 " 0.89 0.97 not top-dressed. 512 Soil " 0.98 1.09 not top-dressed. 513 Subsoil of W/506 " 0.61 0.67 514 Moss patches, pdk. W/506 1.09 1.14 badly mossed. Experimental. Table 1 shows the chemical analyses of the Mairoa soils. It will be seen that in the top three inches of soil there is ample available phosphate on the unmanured land judged by the usual standards in use for ordinary soils. In the samples taken to a depth of 9 inches and in the composite soil (No. W609) there is no great lack of available phosphate judged by the usual standards. The large amount of organic matter shown by the loss on ignition, however, puts the soil in a class by itself. The outstanding feature of the whole series of soils without exception is the high lime-requirement figure. One might compare the phosphate-content of the Mairoa soils with that of the pumice soils considerably to the disadvantage of the latter on which clover grows abundantly. Bone-nutrition troubles have not been known to occur on pumice soils.

In table 2 are given the results of a series of further analyses of Mairoa soils which substantially bear out the figures of table 1. For a hill-soil, fair amounts of available mineral plant-food are apparently present, but the most important fact is the consistently high lime-requirement figure which is supported by its pH figure. The only exceptions are what one would expect, viz., the soils (X563) drawn round the limestone outcrops which show a lime-requirement figure more nearly approaching a normal North Island acid soil with a pH figure indicating decreased acidity. The other exception is (X553) from a farm usually recognized as superior in quality to the others. The worst soils for “dopiness,” as the local farmers call the disease, are “Farmer O'M,” “Farmer McC,” and “Farmer N.” “While the land of “Farmer T” is generally recognized as superior, the samples of soil drawn near the limestone outcrops (separated by lines from the others) are outstanding in their composition compared with the “soil away from the influence of limestone. Mairoa Soils. Calcium Oxide. Extracted by Citric Acid. Extracted by Hydrochloric Acid. Lime Requirement Figure. PH Figure. “Farmer O'M.” No. 1 pasture .15 .59 1.2 5.2 Virgin forest .23 .74 .89 5.8 Northern paddock .15 .57 .99 5.3 No. 2 paddock .13 .65 1.01 5.3 Near limestone .57 1.63 .38 6.3 “Farmer McC.” .12 .53 .67 5.0 “Farmer N.” .19 .84 .75 5.4 “Farmer N.” (Ngapenga No. 2) .20 .81 .95 5.4 “Farmer T.” (good soil) .39 1.00 .56 6.1 There is a further method by which soils may be examined; the determination of exchangeable bases in the soil or the bases which are instantaneously extracted from the soil on treatment with a solution of a neutral salt. Taking sample X565 the amounts of bases extracted per cent, on the air-dried soil are:— Ca 0.165 Mg 0.024 K 0.054 This soil is very rich in organic matter (26.6 per cent, loss on ignition) so that a high degree of unsaturation is probably indicated. According to Russell (p. 218) “Humus is more sensitive than clay to change in calcium content and more rapidly becomes neutral on the addition of successive doses of lime or conversely more easily develops acidity as the lime is washed out.” The same writer (p. 384) gives some interesting figures showing the relation of sour-

ness of soil to the capacity for growing certain plants on it. With a lime-requirement of 0.22 per cent, calcium carbonate on the Harpenden Common, white clover was found to be the dominant growth, of 0.26 per cent, it was fescues, of 0.31 per cent, yarrow, wood rush, and moss, of 0.39 per cent, gorse, of 0.43 yorkshire fog, of 0.53 per cent, sorrel. In the fir woods with lime-requirement of 0.24 the dominant growth was Mercurialis (dogs-mercury) but of 0.52 is was yorkshire fog, sweet-vernal, and thistles, of 0.62 fog and anemone. On the Rothamsted grass plots, 1919 results on the most sour soils with a pH figure of 3.79 there was 64.8 per cent, of yorkshire fog (Holcus lanatus) in the pasture. Where fog becomes dominant the soil may evidently be unusually sour and in need of lime. (One of the dominant grasses of these Mairoa lands is fog.) Finally Russell in discussing the influence of disease organisms in determining the vegetative characteristics of sour soils finds where there is a pH figure of 5.66 to 6.21 there was much “finger-and-toe” in cruciferae, but where there was a pH figure from 6.13 to 7.9 there was little or no “finger-and-toe.” The Mairoa soils are much lighter in texture than those of Rothamsted (a clay with flints), but at Mairoa it is found that with a pH figure of 5.0 to 5.8 finger-and-toe prevents the successful growth of all cruciferous crops attempted. In table 2 are also given the results of two North Island soils of very different types on which dairying is successfully carried on for comparison with the Mairoa soils. The Pastures. A small number of general pastures and cocksfoot grasses have been analyzed. As would have been expected from a pasture devoid of leguminosae, the calcium and phosphoric acid content of the samples from the unmanured land or from land away from the influence of limestone outcrops is low. Where the pastures have been highly manured by top-dressing with phosphates and potash, or those with ground limestone (6006/6007), calcium and phosphoric acid are present in good proportion and in the right ratio for sheep-feed. Where no top-dressing has been applied (6020/1/2), the amounts of calcium and phosphoric acids are low except where the samples are taken near the limestone outcrops, in which case the calcium is far higher (see Table 3). In the cocksfoots analysed separately the same low calcium and phosphoric acid content is found, except from around the limestone outcrops and in one of the limed areas where the calcium content is high. Summing up the evidence which supports liming as an essential to success on the deteriorated volcanic soil of the Mairoa type one may say that,— (1.) The high “lime-requirement” figure indicating an absorption of nearly one per cent, of lime by laboratory methods. (2.) The absence of clovers in the pasture in spite of abundance of potash. (3.) The “finger-and-toe” disease in cruciferous crops.

(4.) The prevalence of moss in the winter pasture. (5.) The abundance of yorkshire fog in the pasture. (6.) The avidity with which sheep forsake pasture even well top-dressed with phosphate to feed on a strip of limed pasture in the same paddock. (7.) The fragile condition of the bones of the animals which show an increase in the organic matter and a diminution of mineral matter. (8.) The rapid recovery of the same sheep when they are placed on a limed paddock. (9.) The good results obtained in the years succeeding a burn. (10.) The fact that pasture growing near the limestone outcrops contains approximately twice as much calcium as that growing away from the influence of the limestone. (11.) Earth-worms manifest their presence in the recently-limed land to an unusual degree compared with unlimed land where their burrows are inconspicuous. all show the immediate need of lime to the land. The conclusion come to from the soil and pasture analysis and the rapid recovery of the ill-nourished animals when placed on limed land is, therefore, that the soil is an abnormally sour one, and that in spite of the fair amount of plant-food present, the clovers cannot nourish, and hence the pasture becomes deficient in the calcium-rich components, the leguminosae, and that lime in some form is necessary to restore the productive capacity to the point at which sheep-farming can profitably be carried on. The writer's grateful thanks are due to his assistants, F. T. Leighton, R. E. R. Grimmett, C. M. Wright, F. J. A. Brogan, and I. J. Cunningham, for the unremitting attention and enthusiasm with which they have discharged their duties in connection with this investigation; also to Mr. J. Lyons and his staff for their reliable professional advice in connection with the sick stock References. 1927 Russell, E. J., Soil Conditions and Plant Growth. 1927 Wilson, Jas., The Principles of Stock-feeding. 1908 Hall, A. D., The Soil.

Table 1. Chemical Analyses. Results, except*, are percentage on soil dried at 100° C. Laboratory No. Locality Volatile Matter. 1% Citric-acid Extract. Dyer's Method, Hall's Modification. (“Available Plant Food.”) Hydrochloric-acid Extract, (“Total Plant Food”) Lime-requirement, % CaCO2 Hutchinson-Maclennan's Method. * On Air-drying. * At 100° C. On Ignition. Total Nitrogen. Lime. CaO. Magnesia, MgO. Potash, K2O. Phosphoric Acid, P2O5 Lime CaO. Magnesia, MgO. Potash, K2O phosphoric Acid, P2O5 On Air-dried Soil. On Soil dried at 100° C. X 284 Mairoa Depts. Experimental paddock, Top 3 inches 41.6 8.52 31.50 0.791 0.117 0.030 0.022 0.012 0.43 0.40 0.13 0.07 0.98 1.07 285 " "Next 3 inches 34.2 21.42 35.30 0.604 0.093 0.016 0.013 0.005 0.34 0.33 0.11 0.04 0.74 0.94 286 " " Lowest 3 inches 42.2 17.04 30.93 0.527 0.070 0.015 0.011 0.003 0.25 0.32 0.10 0.05 0.78 0.94 287 " Highest paddock near road, Top 3 inches 33.9 13.44 32.37 0.783 0.165 0.043 0.029 0.013 0.51 0.45 0.16 0.14 0.65 0.75 288 " " Next 3 inches 28.8 23.20 31.88 0.645 0.125 0.034 0.021 0.008 0.41 0.40 0.15 0.08 0.57 0.74 289 " " Lowest 3 inches 26.6 12.26 28.17 0.511 0.094 0.026 0.019 0.003 0.32 0.38 0.14 0.11 0.70 0.80 W 512 Soil not top dressed, Mairoa – – – – – – – 0.017 – – – 0.07 0.98 1.09 W 609 Composite, Mairoa Soils† Mostly manured. – 8.28 30.09 0.720 0.203 0.041 0.034 0.018 0.51 0.51 0.34 0.08 – – W 506, 507, 510, 512, 514 W 881 Subsoil of 882 3.7 7.54 21.48 0.309 0.080 0.023 0.028 0.003 0.26 0.63 0.53 0.03 0.72 0.77 882 Topsoil, highest land unmanured 4.3 7.62 27.93 0.697 0.165 0.037 0.034 0.012 0.57 0.68 0.46 0.07 0.85 0.92 883 Topsoil, 12 acre paddock 7.1 5.52 23.12 0.501 0.132 0.040 0.019 0.016 0.47 0.71 0.40 0.07 0.74 0.78 884 Subsoil of 883 5.7 5.57 17.54 0.258 0.088 0.022 0.020 0.011 0.29 0.83 0.61 0.06 0.72 0.76 885 Topsoil, Limestone paddock 13.5 8.16 34.23 0.732 0.187 0.032 0.031 0.021 0.39 0.42 0.24 0.11 0.92 1.00 886 Subsoil of 885 12.7 5.36 25.76 0.352 0.091 0.021 0.022 0.008 0.26 0.46 0.28 0.06 0.91 0.96 Analyses by F.J.A. Brogan

Table 2. Chemical Analyses. Results, except*, are percentage on soil dried at 100° C. Laboratory No. Locality Volatile Matter. 1% Citric-acid Extract. Dyer's Method, Hall's Modification. (“Available Plant Food.”) Hydrochloric-acid Extract, (“Total Plant Food”) Lime-requirement, % CaCO2 * On Air-drying. * At 100° C. On Ignition. Total Nitrogen. Lime CaO. Magnesia, MgO. Potash, K2O. Phosphoric Acid, P2O5 Lime CaO, Magnesia, MgO. Potash, K2O phosphoric Acid, P2O5 On Air-dried Soil. On Soil dried at 100° C. Hydrogen-ion Concentration (pH). W 1377 Turakina Valley (loam) 30. 11.10 0.369 0.296 0.112 0.021 0.017 1.79 1.13 0.86 0.07 0.13 0.13 – 1379 Himatangi (sand) 0.7 3.1 0.075 1.155 0.052 0.016 0.003 † Carbonate of lime present.3.41 0.69 0.35 0.01 – – – X 553 Topsoil Otanake 12.9 23.3 0.746 0.394 0.033 0.044 0.006 1.00 0.58 0.27 0.18 49 .56 6.1 555 "slag-manured 7.5 32.8 0.769 0.150 0.038 0.026 0.008 0.59 0.32 0.12 0.02 1,1 1,2 5.2 557 " manured 10.3 30.1 0.830 0.228 0.041 0.032 0.008 0.74 0.38 0.14 0.03 .80 .89 5.8 559 " " 15.3 29.0 0.582 0.154 0.037 0.018 0.005 0.57 0.31 0.12 0.05 .84 .99 5.3 561 " " 19.0 27.3 0.749 0.131 0.027 0.026 0.007 0.65 0.30 0.12 0.03 .82 1.01 5.3 563 " " (round limestone bluff) 9.8 20.4 0.599 0.573 0.087 0.033 0.007 1.63 0.92 0.34 0.15 .34 .38 6.3 565 Topsoil, Mairoa (unhealthy, unmanured) 8.0 26.6 0.789 0.197 0.041 0.025 0.008 0.84 0.44 0.23 0.03 .69 .75 5.4 567 " Swamp (comparatively healthy for sheep) 5.0 19.9 0.454 0.200 0.035 0.027 0.017 0.73 0.70 0.39 0.06 .65 .68 5.4 569 " Ngapaenga, unhealthy 5.7 31.2 0.624 0.205 0.041 0.032 0.009 0.81 0.41 0.15 0.04 .91 .95 5.4 571 " " 8.0 30.3 0.632 0.189 0.034 0.033 0.007 0.836 0.36 0.11 0.02 .91 99 5.8 573 " Maungamangero 4.9 21.7 0.412 0.174 0.038 0.031 0.010 0.85 0.61 0.28 0.06 .72 .75 5.4 575 " " 4.6 17.7 0.322 0.120 0.034 0.017 0.008 0.53 0.37 0.16 0.02 .64 .67 5.0 577 " Waitangururu 3.7 21.1 0.511 0.258 0.031 0.013 0.026 0.87 0.64 0.27 0.05 .62 .64 5.8 Analyses by F.J.A. Brogan

Table 3. Mairoa General Pastures. Lab. No. Locality Date Collected. Ash. Sand SiO2. SiO2. P2O5 CaO. MgO. Mn3O4 SO3 N. Manurial Treatment. Remarks. 6006 Mairoa 10/4/27 12,18 2.13 1.97 1.13 1.20 0.61 0.028 0.92 4.20 6 cwt super. Horse paddock 6 " potash No lime 6007 Mairoa 10/4/27 12.01 1.74 1.64 1.12 1.23 0.60 0.029 1.06 4.36 1 ton CaCO3 Ram paddock 4 cwt. Potash 2 " super. 6018 Otanake -/9/27 12.09 4.80 – 0.72 0.85 – 0.013 – 3.31 Roadside 6019 Horopupu Road -/9/27 12.24 3.68 3.47 0.87 1.08 – 0.026 – 3.08 Limestone outcrop near school 6020 Otanake -/9/27 10.44 3.12 2.90 0.70 0.59 – 0.057 – 3.37 Pdk. No. 1. 8th, side shelter bush 6021 Otanake -/9/27 10.92 2.19 2.11 0.77 0.66 – 0.047 – 3.47 Pdk No. 2 Away from limestone outcrop 6022 Otanake -/9/27 10.82 1.91 1.82 0.69 0.86 – 0.018 – 4.18 Pasture round limestone very gritty 6023 Maunamangero -/9/27 11.96 2.24 2.04 0.86 1.26 – 0.012 – 3.59 Around limestone 6024 Maungamangero -/9/27 10.82 1.49 1.35 0.83 0.79 – 0.028 – 3.76 Away from limestone 6025 Waitangururu -/9/27 12.36 2.50 2.15 0.98 1.40 – 0.026 – 3.53 Grass round limestone outcrop. Gritty 8000 Mairoa 10/4/27 11.59 3.66 3.44 0.66 0.83 0.51 0.037 0.82 2.54 Unmanured 21 years old Yorkshire fog, chewing fescue, danthonis, cats ear, capeweed, piripiri, plantain, etc. Analyses by B. C. Aston and I. Cunningham.

Table 4. Mechanical Analyses. Results are percentage on air-dried soil. Laboratory No. Description of Soil. (Classification of U.S Dept. of Agriculture, modified.) Analysis of “Fine Earth” passing 2 mm. Sieve. Stone and Gravel. Fine Gravel. Coarse Sand. Fine Sand. Silt. Fine Silt. Clay. Moisture and Loss on Ignition 8.3 Composite sample W 609 Loam 0.5 9.4 15.0 14.1 12.3 15.1 27.6