Spring Topdressing and Pasture Management

New Zealand Journal of Agriculture, Volume 95, Issue 2, 15 August 1957, Page 131

Spring Topdressing and Pasture Management

Seasonal Notes by the Extension Division

SPRING TOPDRESSING AND SPRING PASTURE MANAGEMENT ON DAIRY FARMS

BREAK GRAZING should be continued into spring to obtain maximum utilisation of pasture and therefore enable the earlier closing up

of surplus feed for silage. Paddocks to be cropped can be punished by hard grazing, first by milkers and then by dry stock. Late spring topdressing in addition to autumn applications will increase summer feed and production will be maintained further into summer. Paddocks closed early for silage benefit from an extra dressing after being cut; those closed later and the hay paddocks can be topdressed when first shut up. Pastures sown last autumn should be topdressed again in spring. Only grass surplus to the requirements of the herd should be saved for silage. A small part of the paddock closed can be grazed 3 weeks later, and if cut last, this younger more sappy growth can be used to cap and seal the silage. The pit or trench, the bun, and the wedge in order of preference result in the least waste of material ensiled. —J. F. TILL

SPRING PASTURE MANAGEMENT IN THE SOUTH ISLAND

ON mixed farms in the South Island the farmer who is making the most efficient use of his land with stock and crops fre-

quently finds early spring a difficult time to make the best use of available pasture. A straightout sheep or dairy farmer has only two considerations at this time—the feeding of paddocks by stock and the saving of some paddocks for silage and hay. The mixed farmer has to consider also which paddocks to plough for later spring crops and which paddocks he will save for grass and clover seed. Generally if is not until this time of the year that a decision can be made about paddocks which are doubtful as white clover crops. Where it is apparent that suckling clover and other weeds are going to make white clover liarvesting a doubtful proposition the paddocks showing such indications can be turned over for peas or barley. Stock may be concentrated on such paddocks, thus making full use of available feed before ploughing. If lucerne is being grown on the mixed farm, there is no need for the farmer to worry about which paddocks should be shut up for hay or silage, but he can concentrate on grazing the best ryegrass and white clover paddocks so that they give the highest seed yields. White clover seed areas should receive reasonably close grazing until late October or November. Closing too soon will allow the grasses to get away. On the other hand the ryegrasses for seed crops should be allowed to produce leaf, and grazing should be maintained at about Ilin, to 2in. until time for closing, from September to November, depending on locality. Cowgrass areas should be grazed before they are shut up in October to produce hay in December and a seed crop in autumn. Montgomery red clover is also usually shut up in November to December. Sufficient grass paddocks will also have to be reserved as grazing areas during the period that grass and clover crops are shut up. —P. R. BARRER » * *

HILL COUNTRY WATER SUPPLIES

NOW is the time to give some thought to the provision of plenty of clean water for livestock on

hill country, especially where stock numbers have been increased as a result of topdressing and oversowing, and new subdivisions have been made. The success of the deep water-storage ponds made with

the bulldozer, which were described in an article in the November 1956 issue of the “Journal” is due to the siting of the ponds well up the hills and to the method of construction which aims at prevention of loss of water by evaporation and seepage. It is surprising how small a catchment area is needed even in a relatively low rainfall area to keep these ponds operating as permanent sources of water where it is most needed. Where the subsoil is pervious this method of water storage cannot be used, but springs are often present on the lower slopes of such country and the collection of water seepage from these, by metms of tiles leading into a pipe to a water trough, has proved to be another satisfactory way of providing a better water supply on this country. The tiles are put in in the form of a bow across the seepage area below the spring and in addition to collecting all the water available they serve also to drain the area, changing boggy places to dry land. —J. M. BRASELL

* WEED CONTROL IN CEREAL CROPS

* * BY late August or early Septeinber most weeds which are likely to be troublesome in autumn-sown cereal crops are already beginning

to be noticeable. Harrowing of autumn-sown cereal crops at this time is a useful way of controlling annual weeds which have germinated in late winter to early spring. However, in recent years hormone weedkillers have proved extremely effective in killing annual weeds in the young stage and also in controlling Californian thistle. Annual weeds which are readily killed and which are often of economic importance at a later stage are wild turnip, tares, hedge mustard, fat-hen, and shepherd’s purse. The most suitable general-purpose spray is the salts or amines of MCPA at 11b. per acre. MCPA is preferable to 2,4-D as the latter sometimes causes a slight reduction in grain yield. The best time to spray is generally at about the 6in. to Bin. high stage, when the plant has fully tillered. This is most important, as yields may be reduced if spraying is carried out too early, or if it is left too late, germination injury may result. Apart from the general disadvantages of low germination for seed purposes, malting barley loses its quality if the germination is low. Some cereal growers claim that the most effective way of getting rid of Californian thistle on heavy land is by spraying in two successive years in cereal crops. Spraying for Californian thistle still should be done at the same stage of growth of the wheat crop as above, though to cause a more severe check to the Californian thistle a later stage is better. MCPA is the most effective preparation to use.

NITROGEN TOPDRESSING FOR GRASS SEED AND CEREALS

In early September autumn-sown wheat which has suffered a check through wet weather and is looking unthrifty and yellow , frequently gives a good response to a dressing of lewt. of sulphate of

ammonia applied at this time. The vigorous growing, dark green crops do not respond. The majority of ryegrass and cocksfoot seed crops will give an increased yield for a dressing of lewt. or if very yellow 2cwt. of sulphate of ammonia or other nitrogenous fertiliser. On country where there is a sulphur response sulphate of ammonia may result in excessive clover growths. On the other hand it may be preferred if the clover is weak and it is intended to encourage it for the following year. The time to apply nitrogenous fertilisers for ryegrasses is when the paddock is finally shut up from stock. For cocksfoot, spring is the best time. It should be emphasised that nitrogen topdressing will not convert a weedy cocksfoot

crop into a good one.

—P. R. BARRER