SEASONAL NOTES

New Zealand Journal of Agriculture, Volume 71, Issue 4, 15 October 1945, Page 407

SEASONAL NOTES

Lucerne

THE sowing of new areas of lucerne and the treatment and harvesting of established stands, first cuts of which are usually made in November, will be the principal work in the coming month. Sowing New Areas Sowing should not be undertaken until the ground is warm, usually about November, and the seed-bed satisfactory. Prior to sowing periodical harrowing is required to obtain a fine, firm seed-bed and the destruction of germinating weed seeds. Before final harrowing and rolling carbonate of lime should be broadcast at lOcwt. to 1 ton per acre, or half the quantity of burnt lime. If the seed is to be sown broadcast, 1 to 2cwt. of superphosphate per acre should also be applied. Both may be applied the same day as the seed, although some growers prefer to lime about 10 days to a fortnight before manuring and sowing. To ensure a good even strike it. is essential that sowing be shallow, practically on the surface, with seed certainly not deeply buried. In order to avoid leaving vacant ground for weeds to strike, broadcasting after the Cambridge roller is generally adopted. Even distribution in sowing may be obtained by broadcasting half the seed at right angles to the first, using about 91b. of seed each way. A light brush, harrowing is usually quite sufficient to cover or sweep the seed into the roller marks or crevices of the soil. Under certain circumstances, such as on light ground, the seed is drilled at about 151 b. per acre with reverted or serpentine superphosphate through every coulter,' but using turnip or worn grain coulters for shallow sowing. The drilling of straight superphosphate with inoculated seed is not recommended, because of the adverse effect of the former on the culture. Some farmers cross drill, but the second drilling tends to bury the first sowing too deeply. When sowing lucerne under irrigation, if the ground has been dry in the early spring, the land may be irrigated before ploughing and conditions carefully watched to commence cultivation as soon as practicable, while the ground is moist. Ploughing and cultivation in the direction of fall facilitates future irrigation and drainage. Too much water

is apt to induce grass conditions, and lucerne is likely to die out in wet places. Because the young plants are very tender and intolerant of competition, lucerne should seldom be sown with a cover crop. The usual rate of broadcasting after inoculating the seed is from 15 to 201 b. per acre. As inoculation may mean the difference between success and failure, it should not be omitted. When ordering lucerne culture through the mercantile firms it is necessary to state the approximate date of sowing and the quantity of seed to be treated. Instructions with regard to procedure are enclosed with the culture. Early Treatment A good strike of lucerne is not difficult to obtain, but as weeds may choke out the young plants, no opportunity should be neglected before sowing of killing germinating weed seeds periodically with the harrows. Once the lucerne is sown, weeds must be controlled by mowing when. growth is about 12in. high and at a stage before they set seed. Fortunately most spring weeds will not persist after one or perhaps two - cuttings, and the growing lucerne will then have a smothering effect. To

enable the lucerne growth' to . come away the cut material, unless thinly spread, must be removed. Trouble with lucerne stands often occurs about a year after sowing, due perhaps to a lack of inoculation or fertiliser at sowing time, but frequently troubles are due to unsuitable soil conditions, such as poor natural drainage or low fertility. Cultivation Most lucerne crops receive no aftercultivation, growers mainly preferring to sow down new. areas after a stand becomes thinned or . patchy from grass competition. Cultivation . may be undertaken immediately after the first cut, using a grubber fitted with narrow, rounded finger tines. Discs should never be used, as they cut the crowns. Application of 1 to 2cwt. of superphosphate per acre is most beneficial at this stage, while lime may also be applied every second or third year. In old stands some growers cultivate in the autumn and drill Algerian oats, which with the lucerne make useful silage .or hay in the spring. As lucerne is winter dormant, the oats will have little effect on the stand, but will smother weed growth. There should be thorough cultivation of old stands or none at all. With a young stand, ensure that the plants are sufficiently well rooted to survive the type of cultivation intended. A cultivator may be too severe, and in the early stages even light harrowing to kill weeds may pull out many young plants, especially on loose ground. Once these are removed, they cannot

be replaced, as patching of lucerne by subsequent sowing is seldom successful. . . ■

Time of Cutting

.Depending on soil and climatic conditions, two to six cuts may be obtained over the growing period, extending from spring to late autumn. Some growth should, however, be left to come away after the last cut. Time of cutting depends not on flowering, which varies with each cut, but on the appearance of young shoots coming away from the crowns of the lucerne plants. At this stage the old growth is at peak quality and quantity, but will deteriorate if cutting is delayed, while the young shoots growing up in the old growth will be spindly and cut back by the mower.

It is obvious, therefore, that the period for harvesting each cut is rather limited and restricts the area of lucerne that can be conveniently handled on a property. Harvesting frequently clashes with seasonal work, such as shearing, and cannot be put off for’a week, as is the case with a clover crop, which, if necessary, may be utilised for grazing.

As the first cut of lucerne is usually weedy and harvested at an unreliable period for haymaking, particularly in the North Island, it is suitably made into silage, while later cuts, if weather permits, are mostly converted into hay. Conditions over the growing season are generally more favourable for haymaking in the South Island, and grass competition also presents less of a problem. Prime lucerne hay, being high in protein, has proved very valuable as a winter feed supplement to root crops in the south, where lucerne growing is rapidly increasing in popularity.

Harvesting

Lucerne is probably the most difficult of crops to cure as hay. Wind drying rather than sun drying transpires the moisture from the stems through the leaves, which remain green in well-cured hay. Sun drying with too rapid evaporation of moisture results in exposed leaves drying out prematurely and dropping off before the moisture is drawn from the stems. Unless turned, loss may be high and drying very uneven. Weather conditions at time of cutting influence treatment, but usually it is wise to side-rake the crop into loose windrows, rather than leave in the swath. The time in the windrow is very variable in different localities and for different periods of the harvesting season. Under very good conditions lucerne may be windrowed after about 8 to 24 hours and baled only 24 to 48 hours after cutting. For hay to be fit for stacking or baling no moisture should appear when it is twisted tightly. If the baler does

not pick up from the windrow cleanly, the hay would, not appear ready for baling. Cuts late in the season are more difficult to bale, while in hot summer weather harvesting a dry crop during the heat of the day may occasion much loss of leaf. Fine agricultural salt will improve palatability and assist curing, but to avoid the risk of heating in the stack lucerne bales under average conditions should, if possible, be left in the paddock for about 24 hours before stacking.

Grazing Lucerne is essentially a - haying plant. Grazing tends to thin out the stand and shorten its life. Stocking consolidates the ground, which is a condition conducive to grass invasion. Injury to the crowns by winter grazing of sheep is liable to kill out or weaken many plants. There is a danger of stock, particularly dairy cows, bloating on green, unwilted lucerne during grazing.

Brassica Crops

THE green forages (rape, kale, and £ chou moellier) and roots (turnips and swedes) are potentially the most economic crops that can be grown to supplement grassland production. In spite of susceptibility to disease and insect pests which impair their reliability, particularly under warm humid conditions, some 600,000 acres are sown annually in the Dominion. More than three-quarters of the area in both rape and turnips and more than half the acreage in swedes, kale, and chou moellier are grown in districts from Canterbury south. Brassica crops are generally fed off; therefore they have a low labour requirement and build up soil fertility for succeeding crops. Rape and soft turnips are grown under a wide range of soil conditions. Kale, although more drought resistant, requires better soil than rape, while chou moellier and swedes need still better soil and moisture conditions. Manuring of Brassicas There is a saying, “No manure, no turnips,” which applies generally to

the brassicas. Superphosphate is the basis of manuring for any of these crops, but germination may be seriously impaired if too great a quantity of superphosphate is sown in direct contact with the seed in the drills. Tests over a number of years under field conditions in Canterbury showed that turnips sown with straight superphosphate in ,14in. drills at lewt. per acre suffered germination injury by approximately 30 per cent., while with 2cwt. per acre reduction in germination was considerably greater, producing very gappy crops. Rape and other brassicas were similarly affected. Comparisons were made with reverted superphosphate and mixtures of superphosphate and carbonate of lime in equal quantities, and even the heavier quantities of these did not materially affect germination, but greatly increased yields. Young seedlings are unable to survive if strength of soil solution is stronger outside the root hairs than inside, because osmotic pressure on which the plant depends for absorption of plant food is reversed.

Water-soluble superphosphate has this effect in producing a too concentrated solution in the vicinity of seed at this critical period of germination, a condition that cannot be overcome by heavier seeding. Therefore the superphosphate should be partly reverted, either by mixing with lime or by using reverted or serpentine , superphosphate. Superphosphate and carbonate of lime mixed a week before sowing and turned three times before bagging loosely do not reset before sowing. Uneven mixing in the drill is unsatisfactory. 1 Seed is more evenly sown through the seed plates than if mixed with manure. Heavy production of brassicas, especially the leafy types, may be expected in soils naturally rich in nitrogen. Unfortunately it is not practicable to apply soluble nitrogenous fertilisers with the seed, on account of germination injury, and even blood may have this effect if applied in more than small amounts per acre. Blood and bone is frequently used in mixtures, but in ridged crops, where most of the fertiliser is applied below the seed and not in direct contact, no deleterious effect is experienced. Rape Although grown to some extent in every land district of New Zealand, and having a total annual acreage of about 200,000 acres, over half the rape crop is grown on mixed farms in Canterbury. In other fat lamb raising districts rape is rarely grown where the lambs can be fattened off the mothers or on pasture, but is required to finish off the tail-end lambs. Where supplementary crops are needed for fattening lambs there is little doubt that this crop must continue to be

extensively grown, as it is difficult to replace. In the South Island rape is required mainly for the JanuaryFebruary period, and fits into rotations of mixed farms admirably, while building up fertility for autumn-sown cereals.

Sowing

Crops are usually sown . in 7in. drills, or on heavy land in Min. drills, at the rate of 2 to 31b. of seed per acre. Certified seed of Broad Leaf Essex rape and Giant rape is available. As the grazing period is comparatively short, several sowings should be made for a succession ~of feed. In sowing, 4oz. Of turnips or mustard or 81b. of Italian ryegrass or a bushel of oats with the rape will counteract its heating tendency. To ensure that both crops mature together mustard is frequently sown on headlands when the rape is in two rough leaves. Rape should not usually be sown with permanent pasture, but is frequently sown at a reduced seeding with the. short-rotation spring pastures of arable farms and as a nurse crop to pasture in Southland.

Feeding

Crops are ready for feeding off after about 3 months, when a blue tinge is apparent on the leaves. If fed before this stage, scouring is likely to occur, due to excess of protein, making lambs difficult to fatten. Time of sowing is judged so that the crop will ripen as near as possible to the time required for feeding. On the heavier land the growing period is longer, while in a wet season maturity is delayed and growth may be too rank for good fattening. Under dry conditions and on light soils yields may be very disappointing and the crop ripen off prematurely. Rape should be fed off in breaks of sufficient size to last up to a fortnight, and no permanent pasture run off provided, as this may be worm infested. Lambs should not be weaned on to rape in an empty condition, and to reduce scouring and assist fattening they should be allowed a small ration of good hay or chaff.

'Second growth seldom reaches the ripening stage and is sometimes used for flushing breeding ewes. Where autumn-sown permanent pasture is to follow rape it is better to sacrifice this growth by discing and harrowing. Such a course will avoid a late establishment which may be fatal to clovers.

Chou Moellier

Chou moellier, which is annually increasing in popularity in suitable areas, may be sown from now on till February. Spring sowings in October

or November provide late summer feed and the crop may be used on the dairy farm to maintain milk production. Although less satisfactory than rape for fattening lambs, the crop may be grown for autumn feed. For winter feeding chou moellier is early autumn sown. Conditions most suitable are the same as for swedes, which crop it may replace where dry rot or club root makes swede growing precarious. Although not immune, chou moellier is very resistant to club root, and while yield is lower, the feed is more succulent and more suitable for late winter feeding or for feeding to hoggets than is the case with swedes. Sowing Seed may be broadcast or drilled in rows from 7in. to 28in. on the flat or ridged. The usual seeding is from 1| to 31b. per acre, heavier sowings being required for broadcasting or close drilling, which result in more slender stems. Government certified seed is available, there being two kinds, one a leafy type, more suitable for sheep grazing, and the other the Giant thick-stemmed variety, with a lower proportion of leaf to stem, possibly more suited for pigs and cattle. Utilisation The crop is suitable for all classes of livestock. In feeding to the dairy herd there is little waste if the crop is cut near the ground and carted on to grass paddocks for feeding after milking. It should be fed off to sheep in breaks, and grazed rotationally, when two or three successive growths may be obtained, but the stalks tend to damage wool. Under severe winter conditions snow tends to break down the leaves, but the crop is available when other feed may be buried. Under very wet conditions chou moellier presents less difficulty with little waste than is the case when feeding off swedes under such conditions.

Thousand-headed Kale

Thousand-headed kale has a more branching habit than chou moellier, with a higher proportion of leaf to stem, but lower total production. Certified seed of this type is also available. When sown in November the crop should be ready for feeding in February or March. A later feeding in October or November is of value only in a late district.

T urnips

In the North Island soft turnips are sown for production of summer feed for dairy cows, and in the South on light land where rape may be unsatisfactory they constitute an alternative though slower crop, for lamb

fattening. The sowing period ranges from late October to the end of January, but in districts where the grassgrub beetle is a menace, usually towards the end of November and early in December, young crops coming through the ground may be destroyed and crops should be timed to miss this period in the young stage. Sown about Christmas or in January, whitefleshed turnips in drier areas provide useful early winter feed. Yellowfleshed turnips are slower maturing and should not be grown where insect damage is prevalent. Like swedes they are more winter hardy and last longer into the winter than soft turnips. Swedes have a long growing period and may be sown in October or November in swede areas of the South Island, although they are frequently sown after Christmas in the North Island. Where crops are likely to be affected with mottled heart borated basic superphosphate should be the fertiliser used. Ridging is the most popular method of growing swedes and yellow-fleshed turnips, especially under damp conditions, but soft turnips are 'commonly sown on the flat in 7 or 14in. drills at about 9oz. of seed per acre. Seed has been produced in the Dominion during the war because of difficulties of procuring supplies from overseas, and Government approved lines of seed available are grouped as follows: White-fleshed turnips are available under the following classification; N.Z. Purple, Red or Green Globe, the first two being early varieties and

Green Globe corresponding to Hardy Green Globe. Yellow-fleshed turnips are sold under N.Z. Green Top and Purple Top Yellow, also N.Z. Green or Purple Resistant, which are more resistant to club root. • \ - . ■ ■ Swedes are grouped under N.Z. Superlative, Grandmaster, Crimson King, Resistant, and Sensation, the last-named being white fleshed.

Field Carrots ✓CARROTS as a fodder crop are CARROTS as a fodder crop are valuable for all classes of stock. In the South Island they are also used extensively in rabbit poisoning. Although somewhat exacting as regards soil and labour requirements, heavy crops of 30 to 40 tons per acre can be grown on deep sandy loam with good natural drainage under a reasonable rainfall. If soils and cultivation are shallow, forking of the roots is likely- to result. Heavy clay soils generally are unsuitable for the crop. Place in Rotation Because they are ill fitted to compete with spring weeds, carrots are most successfully grown after grass or rape. Rainfall and soil will influence time of ploughing, but this should be deep. In heavier rainfall districts winter ploughing is not advisable. The aim during spring cultivation is to conserve moisture, obtain a fine, firm seed-bed, and destroy germinating weeds in the top layer of

the soil. It is not wise to sow before November in many districts, especially on light land, because if sown too early, the crop may run to seed should conditions prove unfavourable. Sowing Whether planted with the ridger, or on the flat with the drill, the seeding should be shallow and on a rolled surface. Intercultivation is facilitated by drilling at 21in. to 28in. on larger areas, but many unthinned crops are sown in 14in. rows with a light seeding. A good practice is to mix'the seed with about twice the quantity of damp sand a week before ' sowing and stir occasionally. Following this procedure the crop is given a better chance against germinating weeds in the seedbed owing to the rapid strike. Before

the carrots appear germinating weeds may be successfully dealt with by a burner, scorching weeds in the rows. The seed and sand may be sown with the manure after thorough • mixing, allowing Ito 21b. of seed to wt. of reverted superphosphate per acre. Under good conditions much heavier manuring is payable, and when using a ridger much of the manure is placed below the seed. After Cultivation Horse hoeing should be commenced when the rows can be distinguished, taking due care not to cover the young plants. Thinning and weeding in the rows should be undertaken early, when the work is not difficult. The plants should be thinned out from 4in. to 6in. in the rows according to the variety and the crop likely to eventuate.

Weed Control by Spraying Much success has been obtained in Australia, and the results confirmed by tests in New Zealand, with spraying carrots with power kerosene for weed control. Spraying can be carried out at stages from seedling leaves up to the “two fern leaf” stage. After 24 to 48 hours most weed growth is completely killed, especially fathen, willow weed, cress, spurrey, ■■ and young ' docks, leaving the seedling carrots unharmed. The most economical practice is to spray the carrot rows in an Bin. to lOin. band, leaving the row centres untouched until scuffling can be carried out to rid the area completely. The power kerosene is usually, applied at 40 to 80 gallons per acre, depending on the amount of weed present. Unfortunately power kerosene is variable in its content of the chemical ingredients which bring about this weed control, and it is advisable therefore to test, each drum of kerosene by spraying a short, strip of the crop. If results appear satisfactory after 48 hours, the spraying can proceed over the whole area. Although this method of weed control may be particularly applicable to market garden areas, its use on field carrots may be well justified when weed invasion would render weeding and thinning operations very difficult and costly. It has been estimated that materials and labour for spraying cost normally about £3 10s. per acre. . * Varieties The variety sown will depend on the purpose for which the crop is grown and the soil conditions. The heaviest yielders, which require deep fertile soils, are - the long varieties such. as White Belgian. Intermediate and short varieties are grown on shallower soils. Guerande carrots are popular for sheep grazing, because, unless they are heavily sown, they, do not require thinning. This is due to their short, stumpy shape and habit of growing well out of the ground, making them self spreading - without intertwining. The carrot tops, unlike mangold leaves, are of high feeding value. —E. M. BATES, Instructor in Agriculture, Alexandra.