PASTURE TOP-DRESSING EXPERIMENTS IN OTAGO, SEASON 1927-28.

New Zealand Journal of Agriculture, Volume XXXVI, Issue 4, 20 April 1928, Page 245

PASTURE TOP-DRESSING EXPERIMENTS IN OTAGO, SEASON 1927-28.

( Continued.)

R. B. Tennent,

N.D.D., Instructor in Agriculture, and A. A. Hume; A.R.C.Sc.I.; Assistant Instructor in Agriculture, Dunedin.

CENTRAL OTAGO.

With a view to ascertaining the effect of fertilizers, on grassland in the semi-arid region of Central Otago, eleven plots were laid down in that district, three of these being on irrigated pasture, and the remainder on non-irrigated pasture.

In connection with the irrigated plots, it was realized that in order to obtain accurate results even watering over the whole plot would be essential, and, further, that irrigation would have to take place at such times as to ensure maximum growth for harvesting. In the case of two of the irrigated plots this was done. In the case of the third insufficient water was applied, with the result that extremely scanty growth took place over the whole plot, thus giving very inconclusive results. In viewing-the results of these irrigated plots.it must be borne in mind that under the arid conditions prevailingnamely, some 14 in, of rainfall per annum—the limiting factor of pasture-growth is soilmoisture. Growth can only take place when this is supplied by irrigation. No amount of artificial fertilizer can take the place of water. The top-dressing of pastures in the drier parts of Central Otago . must therefore be looked upon as supplementary to irrigation. . The results of the experiments for Central Otago are as under :

Irrigated Pastures.

(12) L. RYAN, GALLOWAY.

This plot is situated on an easy slope of mica-schist soil on Galloway Flat. . The pasture was more than twenty years old, and composed practically of rye-grass and white clover. Other grasses,' such as Poa pratensis and suckling - clover, were interspersed throughout in small quantities. From a stock-feeding point of view there was undoubtedly too great a preponderance of rye-grass. It was anticipated that topdressing would induce a stronger growth of clover. The plot was topdressed on 2nd August, 1927, closed to stock on 10th October; and harvested on 12th December. Results were as follows:—

Summary : Lime showed little increase over the unlimed portions. Superphosphate undoubtedly gave the best results, not only in weight but in composition. White clover and suckling-clover showed vigorously increased growth on those plots top-dressed' with super. Basic slag also showed increased clover-growth, but to a less marked degree. This plot was evenly irrigated during growth, the results being quite uniform.

(13) R. TOHILL, RAGGEDY RIDGE, GALLOWAY.

This pasture, sown down in 1922, was composed at the date of topdressing of rye-grass, white clover, Poa pratensis, crested dogstail, and various weed plants. Situated at a fairly high elevation on Raggedy Ridge, it represented a moderate acreage of similar country. Topdressing took place on 3rd August, 1927, the plot was closed to stock on Ist October, and harvested on 13th December, Results were as below: —

Summary : The results on this plot were unsatisfactoiy, very little growth having taken place. This fact can be solely accounted for by the sparing amount of water applied to the crop. It is anticipated that next year more frequent irrigations will be given, and thus afford a better index to the efficacy of the different fertilizers employed.

(14) G. GARTLY, SPRINGVALE.

The pasture utilized for trial had been sown down six years previous to top-dressing, the chief constituents being perennial rye-grass and red clover. Situated on the western slopes of the Manuherikia Valley, this plot lent itself admirably to even irrigation, and as a result the growth at time of harvesting was most uniform throughout. Top-dressed on 4th August, 1927, the pasture was closed on Ist October, and harvested on 12th December, with results as shown in Table 12.

Summary : Marked differences were observed on the plots treated with superphosphate with and without lime, as compared with the control plots, white-clover growth being most prolific in the superphosphate strips. Basic slag with and without lime also showed up strongly, but to a lesser degree than those strips dressed with super. It is interesting to note that the limed strips gave an appreciable increase in yield over the control strips.

Non-irrigated Plots.

(15) R. J. E. SMITH, WEDDERBURN.

. The pasture selected for this trial had been sown down in 1922 with a mixture composed mainly of perennial rye-grass and red clover. At the date of top-dressing, on 6th August, 1927, the pasture was decidedly weak and open, the red clover had disappeared, and browntop with a slight covering of white clover was mainly predominant. The plot was closed to stock on 21st September, and harvested on 14th December. Results are tabulated below, :

Summary : By observation no differences could be noted on any of the strips treated with the various fertilizers. At date of harvesting the general growth all over the plot was poor, and it would have been more advantageous to have delayed harvesting till a later date. This, however, could not be done. As will be observed, the general yield from the different treatments is low, but quite appreciable gains were recorded on those strips treated with superphosphate. Neither basic slag nor lime showed significant increases.

(l 6 J. CRUTCHLEY, KYEBURN.

A plot was established on the Kyeburn Flats, on soil of a light loamy-nature. The pasture selected represented a -fairly large area of similar country. The pasture top-dressed had been sown down with rape in 1921, a ' mixture of rye-grass and white and red clover being used. At the date of top-dressing, on 10th August, 1927, the pasture had, run out badly, goose-grass . and brown-top showing up strongly. The plot was closed to stock on Ist October, and harvested on 15th December. Following were the results: —

Summary : As will be observed from the above table, superphosphate and lime gave the greatest yield, this being largely accounted for by the remarkably heavy growth of white clover growing on strips receiving this treatment. Those strips sown down with superphosphate alone also gave an ’excellent response, . and to the eye the . difference between them and the control strip was most striking.. Basic slag with and without lime appears to have had little effect. Lime alone does not show results.

(17) S. C. GREER, PATEAROA.

The pasture selected for this experiment had been sown down in 1912 with a mixture of rye-grass, white clover, and crested dogstail.' The pasture previous to this trial had not received any manurial treatment. At the date of top-dressing, on 10th August, 1927, it showed signs of considerable deterioration, the presence of a fairly large proportion of sweet vernal and Yorkshire fog being noted A good sole of white clover existed on the pasture. The plot was closed on Bth October, and harvested on 15th December. Table 15 gives the results. '

Summary : The strips top-dressed With superphosphate showed up very, early after closing the plot, and gave a remarkably good yield. The increased yield over the. control strips' was due largely to increased white-clover growth, which showed up to the s eye in a striking manner. This plot ; was‘another instance of the efficacy of superphosphate during its s first ' year of application. The application of lime alone has not given results during the first year, yet a significant increase is noted

in basic slag plus lime as against basic slag alone. A similar increase is to be noted in comparing super plus lime against super alone.

(l 8 M. A. KINNEY, HYDE.

The pasture used for this experiment is situated on rolling country, the soil being of a light natuie. The annual rainfall of this district is low,' and heavy grass-growth is exceptional. Sown down in 1906, the pasture had run very largely to brown-top, there being only a small proportion of rye-grass and white clover present. The plot was top-dressed on nth August, 1927, closed to ' stock on ,Bth October, and harvested on 15th December, with results as under: —

Summary : As will be noted, the growth of grass was light throughout. Despite this fact it is extremely important to record that : on those strips top-dressed with superphosphate a dense growth of white clover took place. On pastures of this description, such a clover growth is extremely valuable, and is exactly what the pastoralist is seeking. The tabulated results emphasize the fact that super plus lime and super alone gave a much heavier all-round growth of herbage than the . control strips. : Lime alone and basic slag plus lime gave no appreciable increase.

(19) ROBERTS AND CO., MIDDLEMARCH.

The pasture selected for this trial represented a large acreage of similar country. Sown down in 1921, it still remained a fairly good pasture at time of top-dressing, being chiefly composed of rye-grass, cocksfoot, and white clover. Sweet vernal and brown-top were beginning to intrude, however. The plot was top-dressed on 12th August, 1927, closed to stock on Bth October, and harvested on 16th December. Results were as follows :

Summary : Those strips top-dressed with superphosphate showed up to a much better degree than strips receiving other treatment. The increase of white clover on the superphosphate strips stood out quite conspicuously, and accounted mainly for the increase in weight over the control strips. Lime alone showed a significant increase, but basic slag alone did not show any visible signs of having improved the pasture. On first year’s , results super plus lime and super alone proved much superior to any other treatment.

(20) J. BECK, OTUREHUA.

This plot, situated on rolling-downs country under dry conditions, consisted of a pasture sown down in 1922. Although sown to cocksfoot, rye-grass, crested dogstail, and white clover, at the time of topdressing practically a pure stand of cocksfoot -existed, and this was in a very open condition. Very little white clover was noted throughout the pasture. The plot was top-dressed on sth August, 1927, and closed to stock on Ist October, but was not harvested. Strict observation was kept on this plot until the end of January. The rainfall during the growing-period was extremely low, and very little growth took place. At no stage could any apparent difference be noted from the various treatments. The growth did not warrant weighing. It is probable that,' after the winter rains, interesting results will be obtained next season ; for the season 1927-28. there is nothing definite to record.

(2l) T. DOWLING, HYDE.

The pasture utilized for this experiment is situated on rolling country. Over twenty-two years of age, it was composed of browntop, Danthonia pilosa, suckling-clover, and various weed plants. Of an extremely poor nature, it appeared inconceivable that results from

any manurial treatment could be obtained. The plot was top-dressed on 10th August, 1927, and closed to stock on Bth December, but was not harvested. Very little growth took place on the plot. The only difference noted was an increase in suckling-clover growth on those strips top-dressed with superphosphate. No other treatment appeared to have any effect, and at no stage did the state of the plot warrant cutting. On this year's result the expenditure on the various manures

showed no justification

(22) J. E. KEARNEY, RANFURLY.

This pasture had been laid down in 1904 with rye-grass and white clover. During the early part of season 1927-28 the rainfall was

extremely low in this locality, and little growth took place on the plot. At the time of top-dressing, on Bth August, 1927, rye-grass and white clover still existed in the pasture, but in an extremely weak and open

condition. The plot was closed on Ist October, but was not harvested. Although the growth was of such \ a short nature. as to preclude harvesting, the plot afforded a most valuable demonstration. The strips top-dressed with superphosphate stood out very clearly, and were composed of a solid mat of white clover, giving splendid feed. This clover-growth contrasted strongly with the miserable strips of untreated grass, alongside. It was unfortunate that precise results could not be obtained by harvesting, but several photographs, two of which are here reproduced, were taken, and show how successful the

application of superphosphate proved on this pasture. Superphosphate in this case undoubtedly justified its application, and proved an unqualified success in promoting good succulent clover growth. Neither basic slag nor lime gave any visible results. (To be continued.)

of Paired Manure. Mean Green of (S or (N). Estimated Weight of Hay per Acre. Value of Hay per Acre. Cost of - • Manure per Acre. Profit or Loss compared with Lnmanured Plot. lb. : T. cwt. qr. qr. £ s. d. £ £ s- . d. s. £ s. d. d. £ S. d. £ s. d. 24 Basic slag . . . 40-0 S I 14 3 3 8 13 9. 8 0 45 O 13i 12 . 6 (gain) 9 0 15 O I 12 6 (gain) 24 ■ Basic slag and lime 35-i N 1 .10 2. 2. 7 12 6 7x 8. 0 120 1 -9 (loss) 6 X 8 0 O I 9 (loss) 30 . . Superphosphate . . 48-3 . S , . 2 2 p O IO IO O IO 1 1 .0, 1°3 2 9 (gain) 0 I I .0 3 2 9 (gain) 30 ■ Super and lime . . 46-3 S., 201 I 10 . r. 3 IO 1 I 4 °. I, 2. 1 0 (gain) 3 I 14 O 2 I 0 (gain) 36 Lime 3i-7 N .. , I 7 . 2; 2.6,. 17 6 6 0 13,-9 170 x . 9 (loss) 6 0 13 o O I 9 (loss) Control. . 29-1 I 5 i' I 663 6 6 3

Table 10.

Number Plots. Manure. i Mean Green Weight Plot. (S) or cant Estimated Weight of Hay per Acre. , Value of Hay per Acre. Cost of Manure per Acre. Profit or Loss compared with Unmanured Plot lb. T. cwt. qr. £ s. d. £ s. d. £ ' s. d. 20 Basic slag 4-0 N 0 3 2 0 17 6 O 15 0 0 12 6 (loss) 20 Basic slag and lime 4-2 N °33 018 9 180 14,3 (loss) 20 Super .. 3-4 . N 030 0 15 0 I I 0 I I 0 (loss) 20 Super and lime . . 3’9 N 032 017 6 1140 i 11 6 (loss) 25 Lime .. ( .. 4-o N 032 0176 O 13 O 0 10 6 (loss) Control. . . . 3’5 0 3° 0 15 0

Table 11.

Number Plots. Manure. Mean Green Weight of Plot. (S) Non-signifi- or cant Estimated Weight of Hay per Acre. Value of Hay per Acre. Cost of Manure per Acre. Profit or Loss compared with Unmanured riot. lb. T. cwt. qr. £ Si d. £ S. d. £ s. d. 30 Basic slag 30-1 S i 6 1 6 11 3 0 15 O O 8 9 (gain) ■ 30 Basic slag and lime 32-9 S 1 8 3 7 3 9• 1 8 O O 8 3 (gain) 30 Super .. ,38-5 . S 1 13 2 8 7 6 1 1 O I 19 O (gain) 30 Super and lime . . 43-3 ■ S 1 17 3 9 8 9 1 14 O 2 7 3 (gain) 40 Lime 30-2 S 1 6 2 6 12 6 0 13 O O 2 O (gain) Control. . 24-5 1 1 2 5 7' 6

Table 12.

ofNumber Plots.Paired Manure. Mean Green Weight Plot. (S) i-or (N).cant Estimated Weight of Hay per Acre. Value of Hay per Acre. Cost of Manure per Acre. Profit or Loss compared \' ith Unmcnured Plot. 1 Estimated Weight of Hay per Acre. » ■ Value of Hay per Acre. Cost of Manure per Acre. Profit or Loss compared v ith Unmanured Plot. lb. T. cwt. qr. qr. ' £ £ s. d. Cj. £ d. S. £ d. s. £ d. s. £ d. s. d. 30 Basic slag ■5-4 S O 4 3 1 3 9 9 0 O 15 150 0 0 O 13 13' 9 (loss) 9 (loss) 30 Basic slag and lime 6-i N O 5 1 1 6 3 31 I 8 80 01 I 4 43 (loss) 3 (loss) 30 Super . . 9-9 , s 0 8 3 2 3 9 9r I 1 I O OO O0 O3 .(gain) 3 (gain) 30 Super and lime . . 10-4 S 0 9 0 2 5 0 01 I 14 14 0 O 0 O11 11 6 (loss) 6 (loss) 40 , Lime 5'7 ■N 0 5 O 1 5 '0 O0 O 13 13 0 O 0 O10 106 (loss) 6 (loss) Control. . 5-i 0 4 2 1 2 6 6

Table 13.

Number Paired 1 : ■ Manure. Mean Green Weigh of Plot. (S Non-signifi 'or 1 Estimated Weight of Hay 1 . per Acre. Estimated Value of Weight of Hay Hay per Acre. Cost of Manure per Acre. Profit or Loss compared with Unmanured Hot. per Acre. Value of • Hay per Acre. Cost of Manure per Acre. Profit or Loss compared with Unmanured Plot. lb. T. cwt. qr. £ s. d. £ s. d. £ s. d. - 30 Basic slag 14-6 N 0 12 3 3 3 9 O 15 O 063 (loss) 30 Basic slag and lime 15-4 N O 13 2 3 7 6. 180 0 15 6 (loss) 30 Super. .. . . 44'7 S I 19 O 9 15 0 I I O 5 19 .'O (gain) 30 Super and lime . . 47'9 S 2 1.3 10 8 9 I 14 O 5 19 9 (gain) O Lime .. 12-8 N on 1 2 16 3 O 13 O on 9 (loss) 40 Control. . 12-8 Control. . 12’6 N O II I 12-6 O II O 216 3 . on 0 2 1.5 0 O 13 O on 9 (loss) 2 15 0

Table 14.

Number Paired Manure. Mean Green Weight Plot. cr c Significant (S) or Non-signifi-cant (N). Estimated Weight of Hay E per Acre. Value of Hay per Acre. Cost of Manure per Acre. Profit or Loss compared with Unmanured Plot. b (7 or Non-signifi-cant (N). Estimated Weight of Hay per Acre. . Value of Hay per Acre. Cost of Manure per Acre. Profit or Loss ccmpared with Unmanured Plot. lb. T. cwt. qr. £ . s. d. £ s. d. £ s. d. . 20 Basic slag 48-7 N 2 2 2 10 12 6 O 15 0 0 10 0 (gain) 20 Basic slag and lime 52-5 S 2'5 3 11 8 9 180 0 13 3 (gain) 30 Super .. . . 60-9 S ' 2 13 1 13 • 6 3 I I 0 2 17 9 (gain) 30 Super and lime . . 64-0 s 2 16 0 14 0 0 I 14 0 2 18 6 (gain) 30 Lime Control. . .. 41-2 42'9 N Il6o 1 17 2 900 9 7 6 O 13 O 106 (loss)

Table 15.

of Number Plots. Paired , Manure. Mean Green Weight of Plot. Significant (S) or Non-signii-cant (N). Estimated Weight of Hay per Acre. Value of Hay per Acre. Cost ot Manure per Acre. Profit or Lost: compared with Unmanured Plot. 1 Manure. ' Mean Green Weight ; of Plot. Significant (S) or Non-signi i- . cant (N). Estimated Weight of Hay per Acre.. Value of ; Hay per Acre. Cost ot Manure per Acre. Profit or Loss compared with Unmanured Plot. lb.’. T. cwt. qr. . £ s. d. £ s. d. £ s. d. 30 . Basic slag 13'5 •N 011 j 3' 2.18 9 O 15 O 063 (loss) 3Q. Basic slag and lime 14-8,. N O 13 O 3 5.0 180 0 13 0 (loss) 30 . Super . . 26-5 S I 3 I 5 18 9 I I O 279 (gain) 30 Super and lime . . '.27-9 . • S I 4 I 6 1 3 I 14 O 1 17 3 (gain) 40 Lime . . . . 12-7 N on 1 2 16 3 0 13 O 069 (loss) Control. . ... 1-4 0 10 0 2 10 0

Table 16.

Number Paired Manure. Mean Green Weight of Plot. Estimated Weight Significant (S) Non-signifi- ior of Hay cant (N). Estimated Weight of Hay per Acre. Value of Hay per Acre. Cost of Manure per Acre. Profit or Loss compared vith Unmanured Plot. c rt c *C (7 or Non-sign cant (N). lb. T. cwt. qr. £ s. d. £ s. d. £ s. d. ' 24 Basic slag 15’0 N O 13 O 3 5 0 0 15. 0 026 (loss) 30 Basic slag and lime 16-9 S 0 14 3 3 13 9 180 069 (loss) 24 Super . . 25-5 S I 2 1 5 113 I I 0 1179 (gain) 28 Super and lime . . 26-5 S i 3 1 5 16 3 1 14 0 t 9 9 (gain) 35 Lime .. 16-4 S 0 14 1 3 11 3 0 13 0 °59 (gain) Control. . 16-4 II-9 s 0 14 1 0 10 2 3 11 3 212 6 0 13' 0 0 5 9 (gain)

Table 17.