GRAZING TRIALS IN CANTERBURY TO COMPARE CERTIFIED PERENNIAL WITH ORDINARY RYE-GRASS.

New Zealand Journal of Agriculture, Volume 47, Issue 6, 20 December 1933, Page 379

GRAZING TRIALS IN CANTERBURY TO COMPARE CERTIFIED PERENNIAL WITH ORDINARY RYE-GRASS.

R. McGillivray,

Fields Superintendent, Department of Agriculture, Christchurch

In view of the prominence given to the inferiority of typical Southern so-called “ perennial ” rye-grass, compared with that produced in Poverty Bay and Hawke’s Bay, as a result of the work carried out at the Plant Research Station at Palmerston North, it was considered necessary to get some definite measure of their relative merits in Canterbury under typical grazing conditions. It was only natural that local pride of . the Southern growers of rye-grass should cause them to feel somewhat indignant at the condemnation of their strains as regards the perennial character; and while the demand for certified rye-grass induced many growers to lay down areas specifically for seed production purposes, there was a lack of appreciation of the value of the certified strains for grazing purposes in the South Island.

From experience gained through fifty-two simple trials, distributed from one end of New Zealand to the . other, sufficient evidence was available to forecast that the superior yield and persistency of the certified type of rye-grass could be established in Canterbury without the need of a highly accurate method of measurement of the results. . The chief difficulty was to decide on a line of Southern rye-grass which could be viewed as representative. The original trial of 522 lines of Southern seed conducted by the Agrostologist at the Plant Research Station revealed the fact that of these not a single line from the South Island could be viewed as up to certification standard, based on the type and performance of the Hawke’s Bay and Poverty Bay strains. Certainly a small proportion (approximately 3 per cent.) were classed as true perennial, but even these showed a weaker constituted type when compared the whole year round both as broadcast plots and as single plants. Of the remainder, approximately 10 per cent, were a better class of false perennial, and 87 per cent, short-lived and very inferior after three to four months’ growth.

The mixing of a number of lines purchased from merchants as “ perennial ” rye-grass seemed to be the most satisfactory procedure in arriving at what seed should be used to represent the Canterbury rye-grass. In consequence of the inclusion of both the bad and the better types of “ false ” perennials, the pastures sown with the Canterbury mixture were decidedly better after one year than would have been the case had one of the 87 per cent, of bad types .only been selected, but were worse than if one of the 13 per cent, of better types only had been used. Further, in both areas a good seeds mixture was sown additional to the rye-grass, including cocksfoot, crested dogstail, white clover, red clover, and Poa trivialis. Some of these additional species have established and

have spread and filled up bare spaces in the area .sown to Canterbury rye-grass, more so than in the area sown to certified ryegrass, and this feed has materially helped to make the carrying capacity higher in the case of the ■ Canterbury area than would have been the case relatively had a more typical Canterbury pasture mixture, consisting dominantly of rye-grass and clover, been sown. It should be pointed out that where rye-grass is being sown for grazing, or for grazing and. seed production, as distinct from sowing only for the production of seed, such sowings should include white and/or red clover, and under most conditions cocksfoot as well, excepting that cocksfoot may interfere with seed production later on, more particularly in the case of white clover, and especially so on the heavier land. The difficulty of getting a good white clover, rye-grass, and cocksfoot' association on the lighter to medium Canterbury soils is great, but because of its important bearing on palatability and the general thrift of the grasses, as well as on the soil fertility, every endeavour should be made to get white clover established along with the rye-grass.

It was fully realized by those planning the trials that they would not give information regarding the relative meat or wool production capacities of. the two types of rye-grass as dominants in the mixtures. The satisfactory determination of such points, because of the time and attention required, would have necessitated methods too involved for trials conducted in co-operation with farmers. The evidence of these trials up to the present, as shown in this article, indicates the undoubted superiority of certified ryegrass over the . non-certified types used in these trials, and is sufficient to justify the use of certified seed wherever perennial rye-grass is being sown.

The six grazing trials of certified versus ordinary' Canterbury perennial rye-grass conducted in Canterbury by the Fields Division have now reached a stage when a definite interim report can be furnished on their condition and stock-carrying capacity.

■ It should be stated at the outset that the trials were arranged for the purpose of ascertaining the relative grazing and persistency values of certified perennial and ordinary Canterbury rye-grass sold as . perennial rye-grass. Two trials were laid down in March, 1930, and later in that year four other similar areas were established. The names of the co-operating farmers and location of trials are as follows: I. K. Buchanan, Irwell; A. R. Hislop, Amberley.; G. Hall, Hororata; H. Wright Johnson, Dunsandel; Hunter Morris, Winchmore; W. L. Hay, Waimate. Each trial consists of a pair of fields which, prior to the trial, were one uniformly treated field. The trial fields are each 3 acres and are designated “A” and “ B.”

Field A in each case was sown with the following mixture: 25 lb. certified rye-grass, 12 lb. Akaroa cocksfoot, 3 lb. crested dogstail, 2 lb. Poa trivialis, 2 lb. N.Z. white clover, 3 lb. N.Z. red clover, making a total seeding of 47 lb. per acre. Field B had a similar seeding, but Canterbury perennial rye-grass was substituted for the certified type in the mixture. In the first two experiments

laid down (Messrs. Buchanan and Hislop) the rye-grass used consisted of a blend of four lines of certified perennial rye-grass from Hawke’s Bay, and a blend of twelve lines in the case of the Canterbury type. In the other trials under review the certified seed of the Hawke’s Bay type consisted of a blend of thirty-two lines, and the Canterbury of a blend of twenty lines.

In all cases the fertilizer used at the time of sowing was ammoniated superphosphate, applied at the rate of 2 cwt. per acre. The establishment of the areas could, on the whole, be considered satisfactory, although growth in some cases was seriously retarded by the dry weather experienced soon after the laying down was completed.

The grazing of the fields was carried out under a system of alternate grazing and spelling, and in order to obtain full utilization of the pastures the areas were often stocked with sheep at the rate of from twenty to forty per acre. In this way growth was in most cases rapidly fed off. The plants were then allowed to recover before being again stocked. In the main the Canterbury type of rye-grass proved the more rapid in establishment and in the providing of feed, but after the first few grazings the reduction of rye-grass in most of the Canterbury areas was apparent, and after the first year the death rate of plants was high. The certified type has proved much more persistent, and has provided a reasonably good sward despite the intensely dry spells experienced since the areas were laid down.

In the various grazing trials the difference in sward became most apparent during the autumn of 1932. The rye-grass on the “ B ” fields showed a definite thinning, and clovers (also to some extent cocksfoot) took up the running, and in the following autumn and winter fully 50 per cent, of the feed was being produced by pasture constituents other than the rye-grass.

During this time the “ A ” fields in each trial showed a fairly good sward of rye-grass, and there was practically no reduction of the amount of rye-grass, the growth of which, however, definitely depressed the establishment of both the clovers and the cocksfoot.

The certified type has showed to advantage on the lighter types of soil, as well as on the heavier types, while the Canterbury rye-grass has been practically a failure on the lighter types, but has held somewhat better on the heavy soils.

The management of the true type of perennial rye-grass calls for decidedly better control than is necessary in the case of the ordinary Canterbury type. This was clearly demonstrated in some of the trials. When the “ A ” fields were grazed when growth was about 2 in. high, control was most satisfactory, while in cases where a growth of 4 in. to 5 in. or more was allowed good utilization by sheep was not so readily obtained. Observations on the Individual Trials. I. K. Bitchanan, Irwell.— The area on this farm was laid down in March, 1930. The germination of all seeds was remarkably good, the most striking thing about the fields in the early stage being the comparatively rapid growth of the Canterbury type and the light green colour of the foliage. This type was ready to graze approximately

three weeks before the certified type. At this period, however, some heavy rain was experienced, and -the grazing could not .be carried out at the correct time. ' From the New Year onwards the weather conditions were extremely dry, and the drought continued well into the winter. During January the fields in both the certified and Canterbury areas were closely grazed, and . with the succession of extremely drying winds the. areas became badly cracked, and there was a death , rate of plants in the Canterbury area. . During the dry spell the. certified ryegrass area began definitely . to show its superiority over the Canterbury type. In -June an examination of the area showed that the mortality of the plants in the Canterbury area had been . very considerable, although the remaining plants appeared to be doing well. An eye estimate of the percentage of the pasture constituents, carried out in October, 1930, showed that-in Field A about 85 per. cent, consisted of perennial rye-grass, while in Field B about 73 per cent, consisted of perennial rye-grass, 7 with 3 per cent, of red and white clover in Field A and about 10 per cent. . in Field B. . A close examination of the pastures in March, 1932, showed very plainly that the rye-grass in Field B was dying' out, . and being . replaced by a fair, amount, of red and white clover, cocksfoot, and weeds. At the same - time Field A showed a strong sward of rye-grass in which the mortality was negligible,-but the establishment of other grasses appeared to have been retarded by the strong competition of the good type of rye.

A. R. Hislop, Amberley. — This area was established at the beginning of April, 1930, and almost from the commencement dry weather was experienced. The germination of the rye-grass, considering prevailing conditions, was very fair, and the sward could be considered fairly good. An eye estimate of the pasture composition, made in October, 1931, showed some interesting differences in the two fields. In Field A about 80 per cent, of the cover consisted of perennial rye-grass, with about 11 per cent, of bare ground. In Field B 60 per cent, of the cover consisted of perennial rye-grass, with 30 per cent, of bare ground. Red and white clover together occupied about 6 per cent, in each case. This area throughout has been subject to extremely dry conditions, and the amount of grazing has not been so great as would have been the case had normal conditions prevailed. The area at date of writing is in fairly good condition, with the certified area showing up well.i

G. Hall, Hororata. — The trial on this farm was laid down on 27th November, 1930, and was fortunate in getting a certain amount of showery weather at time of sowing, with the result that an excellent strike was obtained in both fields. Dry weather conditions followed, but the plants had maintained a fair hold of the soil and on the whole establishment was good. Dry weather continued until well into the winter, and there was a certain amount of death-rate in the rye-grass in Field B. In March, 1932, an examination of both fields showed that about 50 per cent, of the rye-grass plants in Field B had succumbed to the drought of the summer and autumn. In Field B clovers and cocksfoot were making good growth, but it was noticeable that there was less clover in Field A, which at this time had a dense sward of perennial rye with little else showing. The competition of the ryegrass had definitely depressed the growth of the other constituents of the pasture.

H. Wright Johnson, Dunsandel. — This area was laid down on 7th October, 1930, Dry weather set in practically from the time of finishing sowing, and continued for several months. There was a poor strike of rye-grass in both fields, but rather better in the area sown with certified rye-grass than in the Canterbury area. Owing to weather conditions growth was slow in both fields,, but the Hawke’s Bay area withstood the drought much better than did the Canterbury area. In August, 1931, the certified rye-grass area showed much more growth than the Canterbury, but neither pasture was good. This area was most unfortunate, in that it missed a number of showers experienced in other districts of Canterbury, and since its inception it has hardly received the benefit of a good rainfall.

H. Morris, Winchmore. — The trial on this , farm was laid down on 31st November, 1930. Very dry weather was experienced and establishment was slow. Field B showed most growth in the early stages. Some rain fell in February and both areas benefited greatly. Little difference was noticeable between the two areas, although Field B had slightly more growth than Field A. An examination of the area in October, 1931, however, showed that Field A had made a comparatively good establishment of rye-grass which had tillered out into a fairly good pasture, while in Field B the rye-grass was spindly and prostrate in habit and there was more bare ground to be seen than in Field A.

W. L. Hay, Waimate. — This areas was laid down on 17th October, 1930. The conditions following sowing were very dry, and it was some considerable time before establishment took place and grazing could be done. In the February following sowing, the certified area was much denser in sward and of a darker green colour. Field B was inclined to run away to seed and to show a fair amount of bare ground in the pasture. In November, 1931, both fields were feeling the effects of the drought badly. Field A was dark green in colour when compared with the steely grey of the Canterbury area. A considerable clover growth was present in Field B, but the growth of rye-grass in Field A was such that it had depressed the clover growth. Rain fell in February, 1932, with the result that there was a strong growth in both fields, but especially in Field A, which had shown practically no death of rye-grass during the long dry spell experienced. The rye-grass in the Canterbury area had thinned out, and there was consequently much bare land showing. Cocksfoot was vigorous, and clover came away very well in Field B. General Summary of Interim Results. The accompanying table gives a general summary of the results to 30th June, 1933, showing .the carrying capacity of each of the fields for each season and for the whole period during which the experiments were carried out. .. . :

When the results for the whole period during which each experiment has been carried out are considered, the fields sown in certified rye-grass have in all cases carried more stock than the Canterbury rye-grass fields. These increases expressed as percentages of the

carrying capacities of the Canterbury rye-grass fields are as follows : Experiment on farm of G. Hall, Hororata, 82 per cent, increase; I. K. Buchanan, Irwell, 21 per cent, increase ; A. R. Hislop, Amberley, 22 per cent, increase; H. : Wright Johnson, Dunsandel, 58 per cent, increase ; H. Morris, Winchmore, 9 per cent, increase ; W. L. Hay, Waimate, 21 per cent, increase. Combining all trials the percentage increase in grazing of the certified rye-grass over the Canterbury rye-grass is 31 per cent. Thanks are due to those co-operating farmers who by their help and keen interest enabled these trials to. be carried out successfully on their farms. Messrs. Gorman and Saxby, of the Plant Research Station, and the instructors in the different districts were keenly interested in the experiments and co-operated to the fullest possible extent.

. * The number of days m the first period in each experiment was taken from the date of sowing. This accounts for the relatively, lower carrying capacity in the first period in some of the trials in which pasture establishment was retarded through dry conditions. t It .must be understood that “ sheep per acre ” do not represent continuous carrying of number of sheep per acre stated. This method of expressing the carrying capacity is adopted for convenience and to enable the carrying capacities to be expressed in familiar terms. Grazing was carried out under . a system of intermittent grazing and spelling, the rate of stocking during the actual grazing periods being a high one as a rule—about twenty to forty sheep per acre. Sheep per acre are calculated from sheep-days per acre, which represent the number of sheep per acre multiplied by the number of days’ grazing. By dividing sheep-days per acre by the total number of days m each year or other period stated the equivalent in sheep per acre is obtained.

Seasonal Periods on each Farm. Days.* ■ Carrying Capacity of each Type of Rye-grass in Sheep per Acre.t Increase (+) or Decrease ( —) in Carrying Capacity of Certified over Canterbury Ryegrass, in Sheep per Acre. Certified. Canterbury. G. Hall, Hor or at a. (!) 27/11/30 to 30/6/31 1 216 /. 4’3 2 • 7 .2'7 - 4-1-6 + i-6 ( 2 ) 1/7/31 to 30/6/32 366 4’4 2-0 + 2-4 (3) 1/7/32 to 30/6/33 365 3'4 2-0 x-4 . Results to 30/6/33 947 4-0 2-2 + i-8 T. K. Buchanan, Irwell. (1) 30/3/30 to 30/6/31 457 4-i 3-8 4-0’3 (2) I/7/3 1 to 30/6/32 366 5-o 2-7 4-2’3 (3) 1/7/32 to 30/6/33 365 . 3’2 3’5 -0-4 Results to 30/6/33 .. 1,188 4-1 3'4 4-0-7 A. R. Hislop, Amberley. (*) 4/4/30 to 30/6/31 452 i-3 x-7 — 0’4 (2) i/7/3i to 30/6/32 366 2-3 i-6 4-0'7 (3) 1/7/32 to 30/6/33 365 3-2. 2 • 1 + i’i Results to 30/6/33 1,183 2-2 i-8 4-0-4 H. Wright Johnson, Dunsandel.(1) 7/10/30 to 30/6/31 266 i-4 o-9 4-0’4 (2) i/7/31 to 30/6/32 ' 366 2-0 - 0-9 4-I-I • (3) 1/7/32 to 30/6/33 365 2'2 i-8 4-0'5 Results to 30/6/33 997 1'9 1-2 4-0’7 H. Morris, Winchmore. (1) 30/11/31 to 30/6/31 212 -6 1-7 — O’ 1 (2) i/7/3i to 30/6/32 366 3'2 3-2 4-0-1 (3) 1/7/32 to 30/6/33 365 3'7 3’0 4-0-7 Results to 30/6/33 943 3-o 2-7 4-0-3 W. L. Hay, Waimate. (1) 17/10/30 to 30/6/31 256 2-1 2-5 — 0’4 (2) 1/7/31 to 30/6/32 366 4'4 2-8 i-6 (3) 1/7/32 to 30/6/33 365 3'7 3'3 4-0-4 Results to 30/6/33 987 3’5 2-9 4-0-6

Interim Results of Rye-grass Trials.