NORTHERN WAIROA EXPERIMENTAL AND DEMONSTRATION FARM.

New Zealand Journal of Agriculture, Volume XXXVIII, Issue 1, 21 January 1929, Page 30

NORTHERN WAIROA EXPERIMENTAL AND DEMONSTRATION FARM.

NOTES ON OPERATIONS IN 1927-28.*

The season of 1927-28 commenced well throughout North Auckland with a mild and warm spring and plenty of growth. Towards the end of September, however, cold winds and squalls were experienced, followed by dry conditions, which continued, more particularly on the western coast, until well into the following March. The autumn recovery of the pastures was too late to be of real benefit to the milkingcows as regards yield.

PASTURES.

During the year further marked improvement has been shown in all the top-dressed pastures, which stood up remarkably well to the dry conditions until the beginning of February. The proportion of pasture in which paspalum is well established has been increased from practically nil to some 20 acres, and in the mixture for a further 12 acres of young pasture paspalum-seed has been included, though in the. case of 6 acres sown in the autumn of 1927 very little paspalum is to be seen as yet. The fact that paspalum tends to increase under the conditions prevailing on the farm, where the rye-grass pastures open up during summer, is clearly shown by the gradual spread of the former grass through the older top-dressed and heavily grazed pastures where no paspalum-seed was originally • sown, ' but was later introduced by stock. . . * :

The experience on the farm bears out the assertion that, by continuous top-dressing and good management, pastures which are predominantly rye-grass in the early spring and paspalum-white-clover-dominant during the summer can be maintained and are very desirable. The increase in the proportion of paspalum in the older purely rye-grass pastures is therefore looked on with favour, and steps will be taken as soon as possible, through the feeding-out of paspalum hay, to speed up the process with a view to establishing over the whole farm rye-grass, paspalum, and white clover pastures, with such grasses of the original sowings as timothy and meadow foxtail taking a minor part.

PASTURE TOP-DRESSING.

The funds available for top-dressing are directly dependent on the returns from the dairy herd, and it was hoped that the 1927-28 season would see an extension of experimental top-dressing, combined with further subdivision and the inauguration of an intensive rotational system of pasture grazing. Owing, however, to the prevalence of mammitis in the herd, and the lateness of calving of the majority of the cows due to the difficulty experienced in the previous season in getting them in calf, the top - dressing programme was necessarily restricted to a continuation of that of the previous year. An area of 66 acres was top-dressed at the rate of 3 cwt. of straight phosphate

per acre, 33 acres receiving basic slag and a like area superphosphate. The chief point of interest in regard to the top-dressing results is the relatively greater improvement shown in the supered paddocks. In the first two years those paddocks top-dressed with 3 cwt. per acre of basic slag showed a much better response than those dressed with the same quantity of super. During the season under review the supered pastures showed up to advantage more in the growth of rye - grass, though the slagged paddocks are still preferred by the cows, due mainly to the better growth of white clover and generally shorter and thicker sward. The difference in the sward is particularly indicated by the persistence of pennyroyal and buttercup in the supered paddocks, whereas both these weeds have been almost completely crowded out by the better growth of white clover in those paddocks dressed with slag.

SUPPLEMENTARY CROPS.

Very definite periods of shortage in pasture-production are experienced on the farm in dry summers and during winter and early spring. The aim is to eventually provide for these periods by an increase in the proportion of paspalum and the conservation of excess spring and early summer pasture growth in the form of silage and hay. This provision is contingent on an extension of top - dressing (including special nitrogenous top-dressing), the introduction of more paspalum, better drainage, closer subdivision, and intensive rotational grazing on that portion of the farm already brought into fair pasture by the topdressing already carried out. In the meantime crops such as soft turnips, swedes, and mangolds have been depended on to provide for the periods of shortage.

The entire failure of 4 acres of soft turnips and swedes after repeated sowings, owing to the sudden drying - out of the ground in October (1927), was reflected in the rapid decline in butterfat-production from January on. The mangolds, though standing up to the dry conditions better, also suffered from lack of sufficient moisture, and little growth was made by them until the autumn, resulting in a light crop, which, however, was very valuable for the early calvers. On land such as that represented by the farm the farmer is very dependent on weather conditions in growing root crops, unless extensive and costly underground drainage is carried out or he is fortunate in having a naturally well-drained paddock available. The failure of the crops referred to and the drying-out of the. rye-grass pastures demonstrated once more the importance of paspalum and the necessity for conservation .of the excess early summer growth, especially in the form of silage.

THE DAIRY HERD.

Though the pastures have been improved to a wonderful extent by top-dressing, tripod harrowing, and drainage, and’ the feed available definitely increased, the real stumbling-block in the progress of the farm has been the dairy herd. That the cows are capable of high butterfat-production is evidenced by the returns from those cows which have regularly come to profit early and have not suffered from mammitis. The average for the July and August calvers, which are representative of the rest of the herd, is well over 300 lb. of butterfat, whereas the average for the whole herd of twenty-six cows and sixteen heifers was just over 200 lb. in 220 days. A large proportion of the heifers necessary for replacements in the herd on account of disease were undoubtedly capable of much higher average production, but were more affected than the cows by late calving, followed by dry conditions. Despite, the best efforts of the manager, together with the assistance of Live-stock Division officers, the trouble in regard to getting the cows in calf persisted, as also did the prevalence of mammitis, some twentyfive of the herd having suffered from this disease during the season under review. By the end of October only seventeen of a herd of forty-two cows and heifers were in milk, and the majority of the herd came to profit while, the pastures were falling off under the dry conditions prevailing.’

The value of top-dressing was demonstrated not so much by an increase in carrying-capacity, but rather by the fact that despite the

total failure of the soft turnips intended for use in January, February and March, and the short milking season of the majority of the cowstogether with the exceptionally dry summer, the production of butterfat was some 400 lb; ahead of that of the preceding year; when there was good provision of soft turnips and a good summer rainfall.

FUTURE WORK. . The future progress of the farm is of course dependent on production from the herd, and while 'this remains almost stationary, as it has done despite increased carrying-capacity during the past three seasons, this progress must be slow. The policy for the season of 1928-29 is a concentration on the lines already mentioned in the further development of the area so far brought into fairly good pasture. In this connection subdivision and rotational grazing will play an important part, and the effects of frequent tripod harrowing after each grazing will be noted. Provision has also been made for a definite reduction ,in the area under crops by an extension of hay-production and the introduction of ensilage-making. ' ■ ■

C. J. Hamblyn, B.Ag.,

Instructor in Agriculture, Whangarei

' Loss of Lime or Plant-food from Soils, —“ In New Zealand no. data are available concerning the loss of lime or plant-food from different soils under various conditions of rainfall,” states Mr. T. Rigg in the course of a report on the Washington International Soil Congress. "In the past, agriculturalists have been apt to take the data obtained at such stations as the Rothamsted Station as applying directly, to New Zealand conditions. The work of Professor Hendrick at Aberdeen, and of Professor Robinson in Wales, has shown that the loss of lime and phosphate from their soils differs widely from those of Hertfordshire soils. Similar data in connection with the loss of lime and plant-food from New. Zealand soils are urgently required in order that liming and top-dressing of soils’ may be put on a satisfactory basis.”

* An article on the establishment and first two years’ working of this subsidized farm was published in the Journal for January, 1928.