SEASONAL NOTES.

New Zealand Journal of Agriculture, Volume 50, Issue 5, 20 May 1935, Page 306

SEASONAL NOTES.

THE FARM.

Feed Utilization.

During recent years, because of misconceptions about the relative feedingvalues of such materials as hay, silage, and roots, some gross mistakes in the feeding of stock have occurred. A number of these mistakes have arisen because of attributing to silage a much greater feeding-value than actually characterizes itat times it has been looked upon as a concentrate akin to linseed or to grains of cereal crops and their products, whereas silage, as usually made, approximates a coarse fodder or a roughage. Some guidance in the feeding of silage is provided from the fact that generally i lb. of silage equals in feeding-value 2 lb. of roots, and 1 lb. of good, average hay is equal in feeding-value to from 2 lb. to 2| lb. of silage. Both the above statements are indicative only of approximate values, for they are subject to the important reservation that both hay and silage vary greatly in feeding-value according to variations in a series of factors. It is known fairly well that there is a multitude of differences in the feeding-value of hays. A common cause of these differences is variations in the kinds of plants in the hay and in the proportions of specific kinds present. Another cause of differences, at times substantial, in the feeding-value of hays is the time of cutting. Immature, leafy growth makes the best hay, . and, despite this, farmers at times, because of considering the weather or the bulk of the crop, leave the hay uncut so long that they obtain a stemmy crop which, though heavier, is of less feeding-value than a well-made, immature crop, obtainable by earlier cutting. A further cause of differences in the feeding-value of hays, especially grassland hays, is the manurial treatment of the soil, which operates not only directly upon the composition of individual kinds of plants in the hay crop, but also indirectly upon the proportion of the various-kinds of plants— e.g., phosphates may increase clovers. On account of its double action the influence of manuring may affect greatly the feeding-value of hay. The weather conditions during saving affects the quality , of hay to a much greater extent than many farmers realize — where there is much rain during hay-making the feeding-value may be reduced’ to about half. All these factors already specified as causes of variation in the quality of hay, except weathering, which does not affect silage so greatly, may equally affect silage. This is because the feedingvalue of silage, like that of hay, depends primarily upon the character of the crop from which the silage is made. By no means is’ ensilage a magical process of turning poor herbage into nutritious material. Actually the best result that reasonably may be expected, as a rule, • is that. the silage will be only slightly less nutritious than the crop from which it was made. Sometimes it is substantially less nutritious. This brings up the fact that both in hay-making and in ensilage the changes which occur in the stored material may be of moment. As a rule, in hay, heating is not desired^— where it. takes place to any considerable extent it may be associated with combustion or with the production of moulds. Suitable heating to a slight extent is considered desirable, being known as “ sweating,” which produces a slight aroma in the hay and causes the stacks to settle down more firmly and thereby lessens any tendency to excessive drying, should the hay be left in the stack over a long period. A practical difficulty arises in securing exactly the condition which will result in sweating ” and not bring about the excessive heating which should be avoided.

jj. ; While the changes in the material being made into hay . are of some moment, those in the material of silage .are of prime importance, r firstly because the production of brownish to almost black silage which is associated with excessive heating involves an appreciable decline in digestibility' and nutritive value in comparison with the production of the greenish or yellow silage resulting from lower temperatures, and secondly because the liquid which at times drains from silage contains soluble material of distinct nutritive valuethe loss of nutriment in liquid form from silage increases with the succulence of the herbage, and the loss may be made still greater when the internal moisture of the herbage is supplemented by external moisture due to wet weather at time of saving the silage. ■

.. To sum up, the feeding-value of both hay and silage varies with the botanical composition of the herbage, the stage of maturity of the herbage, the manurial treatment of the soil, the amount of weathering. of the material, and the changes during curing.' Hence it is clear that the feeding-value, of hay . and of silage varies from season to season and from field to field, and indeed there may be substantial variations in the material from different parts of the one field in the same season. Consequently only experience will enable the. individual farmer to determine wisely how to use the hay or silage at hand. However, after allowance has been made for the variations just considered, hay and silage as commonly made may be classed as coarse fodders, the essential difference between them arising from the fact that silage is a watery feed while hay is a dry one, and it is of practical importance that coarse fodders serve most usefully for maintenance instead of for production. The feeding-value of ordinary hay and silage for milking-cows has been demonstrated fully and widely, but many seem not to realize that the yield of milk may be depressed by feeding either or both of these materials in excess. Both normally contain a substantial amount of fibre which lowers their digestibility. Fibre gives bulk, and a certain amount of bulk is necessary in the feed of farm stock generally, but the low yield of cows fed for winter milk production has at times been , traced to excess of fibre' arising from relatively heavy use of hay or silage. The amount of hay or silage that leads to depression of yield cannot be specified varies with the quality of the material and especially with the steminess of the original herbage, and occasionally hay or silage of a particularly leafy nature successfully has been made the dominant constituent of the winter ration of producing animals. The Feeding of Silage. : The nutritive role in which silage is of outstanding value in dairying is as a winter and spring feed for maintenance purposes. Silage being watery is not suitable for use with other watery feeds such as roots. It is not recommended that stock be required to depend upon silage alone any more than it is recommended that other good feeds such as mangels, hay, or linseed should be fed exclusively for any extended period. Fortunately, under normal New Zealand conditions, it is not necessary to attempt to feed stock upon only silage, which generally should be used to supplement pastures just as hay and roots are used ordinarily in that way. Silage at the daily rate of in the vicinity of 100 lb. has been fed with success to dairy cows, but not often is there occasion to attempt to feed more than 40 lb. daily, for usually smaller amounts than this suffice in conjunction with the feed provided by the pastures or otherwise. Silage has been fed with good results to sheep, when used to supplement pastures, at the. rate , of about 2 lb. daily.

Possibly the commonest fault in the use of silage consists in underfeeding it. This fault arises primarily from attributing to it a feedingvalue greater than it actually possesses and overlooking that its feedingvalue approximates that of the green material from which it is made.- For instance, trouble has. been experienced when cows have been subsisting

almost wholly upon silage fed at the rate of from 8 lb. to 12 lb. daily, and as this amount is far below that required for mere maintenance the cows really were being semi-starved, and if this treatment were continued long enough death would follow necessarily.

The Utilization of Root Crops.

, Roots generally, cereals for green feed and chou moellier, before they have declined in quality because of over-maturity all contain relatively low amounts of fibre, and so may be fed advantageously in conjunction with hay. The winter feeding of stock on roots alone is inadvisable in that it gives a ration too watery and too cold, and one likely to set up digestive disturbances. Heavy feeding of roots is particularly unsuitable for old toothless ewes if the roots are intact, and is inadvisable to any type of breeding-ewe or to dairy cattle. Roots may be supplemented suitably with dry fodder such as hay or chaff. The feeding-out of swedes on land which shortly will be sown in turnips, rape,, or swedes should be avoided, as it may lead readily to contamination of the land with club-root and dry-rot organisms. In this regard interest attaches to the fact that chou moellier has been grown successfully on soil known to be contaminated heavily with the club-root organism. - On many farms the pulling and storing of mangels calls for attention in June, especially if the land occupied by the mangel is required soon for another crop, such as oats. But no rule for general application can be laid down safely: in milder districts mangels continue for a longer period to increase in weight, and it is doubtful whether it is advisable to pull such crops early in June if they are not to be used until late August or September, unless the land they occupy is especially required for another crop or likely to become so wet later that it will be difficult to cart off the crop. Mangels should be pulled in good time to allow them to ripen or mature before the stock consume them.

Many sheep-farmers are utilizing mangels successfully without storing them. Customarily, broken-mouthed ewes are turned in to eat off the tops, and the roots are then harrowed out in “ breaks ” some days before the sheep are given access to them. The feeding takes place relatively . late in the season when the mangels, before being dislodged, have undergone a certain amount of natural ripening. Freshly pulled mangels are more subject to injury by frost than those that have been pulled for a few days, and, because of this, if at all possible, broken mild weather should be chosen for the work of pulling. When pitting is to be done, the throwing of the mangels into small heaps, covering the heaps with leaves removed from the roots and leaving them for somewhat more than . a week before carting, is favoured by some as leading to better keeping of the roots in the pit. 1 The practice of allowing stock to fall markedly in condition before commencing the consumption of reserves of feed such as silage, 1 hay, and roots cannot be commended. Its objective may be the possession of reserves of feed in the event of a severe late spring, an objective which, of itself, is quite commendable, but looking to the future in this way may lead to undue neglect of the current requirements of stock, especially if subject to the ravages of parasites, and in any case provision for a severe spring is better made much earlier.

Detailed information about the feeding of other materials such as chaff, grain, bran, straw, &c., to the various classes of stock may be obtained from officers of the Fields Division.

General Pasture Work.

Any top-dressing that still remains to be done before the spring should be ; carried out as soon as possible : a special benefit of pre-winter topdressing is stimulation of growth before the low temperature of the soil

leads to the pasture becoming dormant until the spring. Just when it becomes too late to obtain - this benefit from pre-winter top-dressing varies according to geographical position, but it is certain that delay now widely is inadvisable. Although, if at all possible, top-dressing should be carried out before the most inactive period of pastures, it may be advisable at times to top-dress during this period as an alternative to inconvenience, and, possibly, inefficiency resulting from spring top-dressing being associated with an unduly heavy rush of work. The influence of phosphatic and potassic manures and of lime applied in the dormant season is not lost, but is merely delayed until the warmth necessary for growth returns. But the position in regard to soluble nitrogenous manures seems very different judging from field experience, which indicates that if conditions unfavourable for growth obtain for any considerable time after the application of such manures their influence is much lessened.

When possible, hay, silage, and roots should be fed out on pastures showing evidence of current ravages of the grass-grub : surviving plants benefit from the consequent additional trampling, and some resowing of seeds contained in the hay may occur to assist in thickening opened swards.

In many districts of-relatively mild climates pastures, especially ones containing a substantial amount of rye-grass, if closed towards the end of May or in early June will provide valuable fresh feed inflate July and August. The amount of such feed may be increased by the use of a nitrogenous manure such as sulphate of ammonia, from which the results are best when used in conjunction with phosphates and often lime also, while comparatively poor results are likely to be obtained from sulphate of ammonia alone. The desirability of such nitrogenous top-dressing depends largely upon a shortage of feed in late winter or spring.

General Cropping.

■ At this season it is of practical importance that one. of the main factors limiting yields of crops is insufficient tillage, particularly before and also after the sowing of the seed. Under many conditions it would be well to begin straight away preparatory cultivation for such crops as mangels, potatoes, and lucerne. In that preparatory cultivation the two deep ploughings that-are sometimes recommended are not always advisable—the surface layers of old swards may contain large numbers of weeds and of their seeds. A first deep ploughing will bury many of these which a second deep ploughing will bring back to the surface, where they readily give trouble, whereas if buried deeply enough the seeds at least cause no trouble. •Often the necessary seed-bed can be obtained by skim-ploughing and disking well ahead of sowing, thus pulverizing the surface soil which later is turned down deeply by a full ploughing. In order to place the weedinfested surface layer well underground the use . of a skimmer attachment is at times of value.

When the soil is not too wet and cold, oats and barley may at times be sown with success in June to provide useful spring feed. Such crops usually respond profitably to a dressing of from i cwt. to 2 cwt. an acre of superphosphate, and should not be drilled deeply. Treatment of seed against parasites such as smut is as desirable as for the seed of cereal crops sown earlier.

When being broken up for arable cropping “ twitchy ” old pastures should be utilized in a different manner from old pastures which are not “twitchy.” Information about this is available from officers of the Fields Division, and is contained in these notes in the May, 1934, Journal. Drainage and the provision of pits and trenches for ensilage offer’ scope tor valuable winter work on many farms. ',

— R. P. Connell,

Fields Division, Palmerston North.