FARMING PUMICE COUNTRY

New Zealand Journal of Agriculture, Volume 70, Issue 4, 16 April 1945, Page 399

FARMING PUMICE COUNTRY

By

C. R. TAYLOR,

7 •* Fields Instructor, Rotorua.

SOME forty years ago a curious wasting disease affecting cattle and sheep was reported in the Tauranga district, where it was known for a short time as Tauranga disease. With .the development of land in the County of Rutorua* particularly in the bush country ot Mamaku and Kaharoa, a similar condition to Tauranga disease was very soon noted in ruminant stock after from 6 to 12 months’ pasturage. This so-called disease was often spoken of as “the skinnies,” or more commonly “bush sickness.” Later still farmers in the Taupo County and the South Matamata County also complained of severe stock losses from an obscure wasting complaint that seemingly defied all types of treatment In these instances, however, it was almost entirely open fern and tussock country that gave rise to the trouble, thus demonstrating that the popular name of “bush” sickness was a misnomer.

DURING the period of its almost unchecked incidence, extending over a third of a century, this malady was the greatest single hindrance to the normal development of the pumice country, just as the discovery of the remedy of this deficiency disease was one of the greatest triumphs of agricultural science. Mr. B. C. Aston, late chief chemist of the Department of Agriculture, together with a small but enthusiastic band of co-workers, was responsible for a tremendous amount of research into this problem, and it was he who first introduced limonite in 1931 as a practical preventative and remedial treatment of bush sickness. His name will be chiefly remembered in this connection, for he retrieved the fortunes of hundreds of farmers by his discovery that the complex iron ore finely powdered and mixed with salt (50:50) as a lick, or suspended in water and used as a drench, both cured bad cases of bush sickness and also successfully prevented its development.

At this time it was held that a deficiency of iron in the soil and pastures was responsible for bush sickness—hence Aston’s use of, inter alia, the iron compound “limonite.” Later

Australian and New Zealand research workers showed that limonite owed its potency to its cobalt content. Pumice Country Sound Nowadays nobody in the pumice country talks of bush sickness, for there is no evidence of that condition in stock. Simple cobaltsalt licks and cobaltised fertilisers have made the pumice country as economically sound as any other farming district of the Dominion. The productivity of the average dairy herd now bears favourable comparison with figures that could be assembled by any other dairying centre of repute, while the butterfat yield per acre ranges

from 1201 b. to 2001 b. Where dairying s not carried out three breed“L'"'? per acre can safely “* anTafLt thirds of their lambschiefly Southdown —can be delivered to the works as 32-36-pounders durins January and February,

In addition to the ewes one cattle beast of the beef breeds to 3 acres can also be carried satisfactorily. In numerous instances small flocks of breeding ewes are now carried along with dairy herds, and these usually do very well following the cows,, especially the lambs, which often average 401 b. and more relatively early in the season. In support of the above general observations it will be of interest to* . examine figures compiled by the Government Statistician and summarised annually in the A. and P. statistics. Those presented refer to the Rotorua, Tauranga, and Taupo Counties only, but from the writer’s intimate knowledge of the southern portion of the Matamata County, including the districts of " Putaruru,. Lichfield, Puketurua, and Tokoroa,. readers may be assured that equal progress has taken place in this area. These figures reveal that in 15 years from 1926 permanent pasture has increased 47 per cent.; dairy cows have increased by 113 per cent.; other cattle by 55 per cent.; sheep shorn. 200 per cent.; lambs tailed by 210 per cent.; milking machines by 151 per cent., and shearing stands by 230 per cent. Although there is only half as much again of permanent pasture in 1941 as in 1926, the number of dairy cows has more than doubled; other cattle have increased by more than.

half, while sheep shorn and lambs tailed are now three times as great. The slight decrease in dairy cows and the tremendous increase in sheep in 1941 is undoubtedly a reaction to wartime conditions. The figures are, however, conclusive evidence of the huge increase in carrying capacity between 1931 and 1941, or from the time cobalt-bearing limonite and, a few years later, cobalt salts were first made available. Corroboration is given in the great growth in output of the Ngongotaha butter factory from 350 tons in 1926 to 1,584 tons in 1941; and of the Tokoroa cheese factory from 210 tons from 28 suppliers to 736 tons from 41 suppliers within the same period. More recent data concerning the number of fat lambs railed to the works through the Rotorua station are typical of the numbers sent through other centres such as Putaruru, Tauranga, and Te Puke. The stock detailed below was drawn from the Rotorua County only:—

The numbers of fat lambs railed to the works, together with their average weights, are an excellent criterion of the progress made in the pumice country since the advent of cobalt for the very good reason that it was always well known that lambs were highly susceptible to bush sickness. The figures quoted have been obtained from reliable sources, but owing to the work involved in compiling them, no attempt has been made to go back beyond the season 1938-39.

Actual Experiences

A few actual experiences of farmers before and after the discovery of limonite, and later cobalt, follow. One man at Tokoroa in the 1930-31 season milked 50 cows on 130 acres for the production of 10,0001 b. butterfat. The herd was a fairly well-bred one, and there was no shortage of feed or lack of general attention. In the 1942-43 season the same farmer milked 85 cows on a little over 200 acres, besides running a few breeding ewes and several head of young stock for a production slightly exceeding 24,0001 b. 1 fat. This season 108 cows (inclusive of 30 heifers) are in the herd, and yield to date promises to be over 30,0001 b. for the season. Still a further example of actual experience of cobalt topdressing comes from the Native Department, Rotorua, concerning an area of land

known as the Tihiotonga Block. Of a total area of 2,600 acres approximately 2,000 acres are in good permanent pasture. Before the use of cobaltised topdressing it was found practically impossible to keep sheep on the property for more than six months at a time without their developing bush sickness, and it was utterly hopeless to think of fattening lambs or bullocks. In these circumstances it became the customary practice of - the management each season to remove all breeding ewes to healthier country just prior to lambing, while cattle would be treated in much the same way but at longer intervals. Fresh lines of stock would then be brought in to replace those shifted, and so the process would be repeated from year to year. Since cobaltised fertilisers have been regularly usedapproximately 6 to 7 years at 2 to 3cwt. annually the general position on this property has so vastly improved as to be hardly credible. Last winter, for instance, with 100 acres of swedes and 1,900 acres in grass, the stock carried was as follows: 1,278 bullocks (2J-3|-year-old). 900 breeding ewes. 480 hoggets. 200 dry ewes. 286 wethers. The bullocks had been brought on to the property in April, 1944, and by January, 1945, over 600 had been slaughtered at an average weight of 8501 b. By May, 1945, it is expected that at least 1,200 of the 1,278 will have been disposed of for an all-over average of 8001 b. In the 1943-44 season 800 bullocks and 400 cows were fattened for averages of 8501 b. and 6401 b. respectively. The 900 breeding ewes wintered produced slightly in excess of 100 per cent, lambs (a figure somewhat lower than that obtained over the past few years), and it is anticipated that the majority of these will go to the works as fats about mid-February, the balance being fattened and disposed of by the end of May. Last

season’s over-all average weight for fat lambs was 371 b. Following the disposal of roughly half the wintered bullocks by the following December- and approximately 75 per cent, of lambs by mid-February of each year, it is necessary to purchase extra stock to consume the prolific pasture growth always available during the late summer and autumn. In January of this year 1,500 shorn wether lambs were bought, and of this number most are expected to fatten and be ready fordisposal by the end of May, the few that are t left being retained and sold as fats in the following November or December. Last season 2,100 4-tooth wethers were handled ✓as just described, and all but the 286 referred to previously as being wintered on the property were fattened by the end of May, 1944, averaging 70.91 b. ' That other factors have played their part in this vastly improved position of animal health and productivity, apart from the use of cobalt in licks and fertilisers, must be admitted. Of importance in this connection is the now almost universal use of Govern-ment-certified strains of seeds; the more regular employment of greater quantities of artificial fertilisers for topdressing purposes; improved - water supply systems; herd testing; more rigid culling, and better attention to breeding problems.

Cobalt Essential

Nevertheless, it is a fact that the best pasture and farm management could not succeed in keeping stock healthy without, that essential element. This is not to overstate the position in any way, for from the writer’s own experience of the "bad old days” scores of apparently wellfed and otherwise carefully attended dairy herds did well if they succeeded in averaging 1501 b. fat per cow. More often than not the figure hovered around 1201 b., while in all too many cases useful-looking animals would yield only 80-1001 b. for the season. Likewise grown sheep would literally "die like flies” within 12 months of

HEALTHY AND BUSH-SICK STOCK

their coming into the bush sickness

areas; lambs, of course, refused to fatten, the majority dying before Christmas unless disposed of before this time. Consequently it was a common practice to sell ewe and lamb together to some outside buyer whenever possible, the seller purchasing a fresh line of 5- to 6-year-old ewes each year. Rearing calves was also a tiresome and heart-breaking job, many dying before weaning time, and of those that survived this period most would be casualties before the following winter was over.

The provision of farmers’ finance soon became something to be dreamed, but rarely secured. Banks, stock firms, other lending institutions, and even the Government soon became chary of advancing financial assistance to hard-pressed settlers after a short but costly experience in pumicecountry securities.

Effect on Management

This is a brief outline of the average conditions obtaining in the pumice country before the advent of limonite and cobalt, and what the discovery of these substances has meant to the farmer and those that trade with him. But what do these discoveries involve in terms of general farm management? Actually very few differences exist today between the treatment of what might be called normal country and pumice country. The making good of a cobalt deficiency is, of course, the chief point of difference, and this is very simply achieved by topdressing with a prepared cobaltised fertiliser such as cobaltised superphosphate or cobaltised serpentine superphosphate. It has been found that soz. cobalt sulphate per acre per annum is adequate, i.e., lcwt. of

cobaltised superphosphate containing 61b. cobalt sulphate per ton. Should more phosphate be required over and above the amounts supplied in the cobaltised fertilisers, then straight superphosphate or serpentine superphosphate can be employed at a slightly lower cost. Cobalt licks are quite unnecessary when cobalt topdressing has been applied. Unlike many other soil types, pumice land is not very responsive to lime. Phosphates, however, are as naturally lacking in the pumice soils as in most other soils of the Dominion, and 3cwt. per acre (when available) of superphosphate or serpentine superphosphate regularly applied is ample to meet this deficiency and maintain stock and pastures at a high level of productivity. The following table serves to indicate the general trend of fertiliser consumption for the period between 1926 and 1941. The increased consumption noted is largely consequent upon the discovery of cobalt, the farmers’ economic position having so improved as to enable him to apply more and more fertiliser to his pastures.

The tonnages indicated were delivered through the railway stations mentioned. Pasture management in the pumice .country today is very similar to that practised in other progressive districts. In general practice certified strains of grass and clover seeds definitely produce the best results, and consequently should be employed whenever possible. On some of the coarser pumice-soil types cocksfoot grows far more naturally than, does perennial ryegrass, and for this reason should be used more extensively than it is in permanent pasture mixtures, ryegrass being reduced in quantity proportionately.

Whereas in the period when bush sickness was prevalent it was almost impossible to ’ control pasture growth by grazing alone, owing to the poor and depraved . appetite of affected stock, nowadays, with an average winter of four months to prepare for, it is quite unnecessary to do the amount of 1 topping that at one time was common on cobalt-deficient farms and destroy this valuable surplus material by burning. With presentday carrying capacity and stock normality very little feed goes to waste; in fact, to secure sufficient hay, ensilage, or both to cover requirements over the winter season adequately it is usual each spring to shut up from a quarter to one-third of the grassland on the farm. Such areas are generally closed either in September,

October, or November, after receiving a good dressing of cobaltised fertiliser, the November cuts generally being ensiled, while the later ones are saved for hay. All breeds of dairy and other cattle today give equal satisfaction in so far as their general health is concerned. No longer is it necessary to choose breeds for their natural superior stamina, which enabled them to resist more strongly an onset of bush sickness. At present Jerseys far outnumber the total of all other breeds, but this is not to infer that the Jersey is the only type worthy of consideration, reference merely being made to it because at one time the breed was very commonly regarded as being more susceptible to bush sickness than any other type. Sufficient has been said, it is hoped, to bring into-high relief the wonderful progress made in the past 10 to 15 years, largely as a direct result of the introduction of cobalt, and to remove for ever the stigma of bush sickness from the pumice lands. Great as has been the advancement made in the period under review, it will, however, prove insignificant in comparison with the future of the vast area of volcanic land still awaiting the attention of man.

Readers are referred to the Department of Agriculture’s Bulletin No. 180, “Cobalt Deficiency in Sheep and Cattle,” which has been prepared in collaboration with the Cawthron Institute and is available from offices of the Department of Agriculture at Auckland, Wellington, Christchurch, and Dunedin. . This bulletin gives up-to-date information relative to all methods of correcting cobalt deficiency.

Acs. in No. dairy No. other No. sheep No. lambs No. milking No. shearYear. perm, pasture. cows. cattle. shorn. tailed. machines. ing stands. 1926 172,954 32,214 40,209 55,298 37,595 458 56 1931 226,256 48,953 50,243 80,096 45,739 683 71 1936 258,740 69,435 43,645 9,896 52,734 897 95 1941 265,314 68,534 61,792 165,184 119,577 1,151 185

Season. No. of lambs. Average weight over season. lb. 1938-39 .. 17,977 lb. 311-1939-40 .. 16,911 344 1940-41 .. 22,699 361 1941-42 .. 33,248 35 1942-43 .. 47,028 354

Station. 1926. tons. 1931. tons. 1936. tons. 1941. \ tons. Rotorua . . 1,699 3,528 5,250 12,369 Mamaku . 118 129 , 151 267 Putaruru . 8,188 9,811 11,417 16,979