EXPERIMENTS WITH “RADIO” MANURE.

New Zealand Journal of Agriculture, Volume XXIV, Issue 1, 20 January 1922, Page 33

EXPERIMENTS WITH “RADIO” MANURE.

SECOND YEAR’S RESULTS.

T. H. PATTERSON,

H.D.A., Instructor in Agriculture, Auckland.

In the March, 1921, issue of the Journal was published an article on tests with “ Radio ” manure used with autumn-sown grassland as a top-dressing for permanent pasture. The report gave the results of trials covering one season, and indicated that coaldust— makes up 60 per cent, of the weight of Radio manure—had a depressing effect on the grasses and clovers, lowering the crop-yields in every case. With further results now to hand after another year’s observation, and, in addition, the weights of hay and green-stuff respectively obtained from top-dressed pasture and grass plots laid down with the object of testing Radio, fresh evidence is furnished upon which to base conclusions regarding this fertilizer.

From this table it will be observed that the application of Radio manure to plot 2 has increased the .crop-yield for the first two years about 26J per cent, over and above the check plot, which received no manure. Taking the average of the two Radio plots, its application has increased the yield of grass 13I per cent, over and above “ no manure." Superphosphate alone, without the coaldust and lime, is slightly better than when in combination with them in the proportions which make up the Radio mixture. Superphosphate and lime on plot 7 have brought about an increase in yield of slightly over 44 per cent, over and above “ no manure.” If it is taken over the two years it has proved over 16 j per cent, better than plot 2 (Radio), or.over 30 per cent, better than the average of the two Radio plots. The yield from plot 3, which received superphosphate alone, is over 5 per cent, better than that from plot 8, where the same amount of superphosphate was used, but with an equal weight of coaldust in addition. The added coaldust has lowered the yield. The superphosphate-lime combination has increased the crop-yield on plot 7 nearly 22 per cent, . over and above that on plot 8, which received a superphosphate-coaldust dressing.

Summarizing the results since the laying-down of these plots in grass in the autumn of 1920, it is plain from the evidence to date that coaldust has lowered the yield wherever it was used. Taking superphosphate as a base, the lime added to it improved the fertilizer mixture, as shown by the increased yields. When the coaldust was added to superphosphate, or both superphosphate and lime, the mixture was not improved, but depreciated in value as a manure. It is clear that the Radio mixture would be better without the coaldust, as this affects adversely the good effects of the other ingredients.

Though not quite relevant to the present problem as to the value of coaldust as a fertilizer, the evidence furnished by these experiments shows that the opinion held by many farmers and othersnamely, that a soluble manure like superphosphate is a mere stimulant, and produces no good lasting effect —is erroneous. The good effects of the small amount of superphosphate applied with the grass-seed have been maintained throughout two seasons. I know of no reliable field evidence to the contrary.

RADIO AS A TOP-DRESSING ON PERMANENT PASTURE

In addition to the foregoing carefully controlled experiments at Motuihi Island, the field adjoining the Department’s Experimental Area at Albany, and leased for grazing purposes, was secured in June, 1920, and set out in six plots. Owing to failure to satisfactorily negotiate with the then lessee we were unable to set out this area so as to include checks, as at Motuihi. Further, for the same reason, we were unable to shut up the top-dressed plots in 1920 and cut for hay in order to make comparisons as to the weight and quality of material produced. This season, however, through the courtesy of Mr. A. Potter, of Albany, who now has the grazing-rights of the area, we were enabled after again top-dressing the plots to shut it up and cut for hay.

The results from the foregoing test, in so far as one can judge from such evidence (which is certainly better than' opinions given after an eye inspection is made), show that the Radio plot 2 compares very unfavourably with plots 3 to 6. Next season it is the- intention to top-dress the plots at Motuihi and Albany, repeating the fertilizer ingredients previously used, both as to kind and quantity, and bring these trials to a close.

Dairy-produce Store.- -The Smithfield Freezing-works, near Timaru, have been officially appointed a store for the storage, cooling, or freezing of dairy-produce prior to export.

New Zealand Shorthorn Herd-book. — xvii (1921) of this publication has now been issued. We acknowledge with thanks receipt of a copy from the Shorthorn Society.

Certificates in Beekeeping. — Since classes in beekeeping were instituted in 1915 at the Ruakura Farm of Instruction eighty-one persons have passed the examination held at the end of each season and gained the Department’s certificate in beekeeping. Of this number twenty-eight passed in the 1920-21 season.

Birds and Root Crops. J. W. Deem, Fields Instructor, Wanganui, commenting on the sowing of this season’s root crops in the Wanganui and Taranaki districts, states that small birds have been particularly troublesome, and expresses the opinion that unless united efforts are made to control them it will be extremely difficult in future to get good stands of root crops in many localities. Sowings of mangolds appear to have suffered most severely this season.

* For particulars of the method adopted to obtain the percentage yields, which provides a fairly reliable basis of comparison, allowing as it does for disturbing factors, readers are referred to the previous article in the March, 1921, Journal.

Plot No. • Fertilizer used when laying down Pasture. Yield per Acre of Green-stuff. Percentage Yield.* Tons cwt. qr. lb. I Check (no manure) 4 6 2 4 100-0 2 Radio, 336 lb. (3 cwt.) per acre 5 7 I 0 126-6 3 Superphosphate, 67-2 lb. per acre . . ' 5 5 3 ■' 8 127-7 4 Lime (burnt), 67-2 lb. per acre 3 4 3 2 8o-o 5 Coaldust, 201-6 lb. per acre 3 9 0 27 87-5 6 Check (no manure) 3 17 I 5 100-0 7 Superphosphate 67-2 lb., and lime 67-2 lb. per acre 5 19 1 21 144-3 8 Superphosphate 67-2 lb., and coaldust 201-6 lb. per acre 5 8 0 9 122-4 9 Burnt lime 67-2 lb., and coaldust 201-6 lb. per acre 4 16 I 26 102-8 IO Check (no manure) 4 19 I 4 100-0 ii Radio, 336 lb. (3 cwt.) per acre 5 0 0 1 100-7 12 Ephos basic phosphate, 3361b. (3 cwt.) per acre ■ 5 10 2 18 III-5 13 Ephos 168 lb. (i| cwt.), and superphosphate 168 lb. (11 cwt.) per acre 6 15 I 7 • 136-3 14 Basic superphosphate 112 lb. (1 cwt.), bonedust ii2 1b. (1 cwt.), guano 112 lb. (1 cwt.) per acre 6 0 2 26 121-6

The average returns from the Motuihi Island grass-plots over the period of two years (1920 and 1921) are given in the following table:-

Plot No. Fertilizer used. Yield of Hay ' per Acre. . Remarks on Standing Crop. I Malden Island guano i| cwt., and carbonate of lime i J cwt. per acre (applied 29/7/21) Cwt. 14 ' qr. O lb. 2 Poor plot. 2 Radio, 3 cwt. per acre (applied 29/7/21) 21 2 5 Heavy with Lotus hispidus (angustissimus) near one end of plot. 3 Basic slag, 3 cwt. per acre (applied 29/7/21) 32 I 18 An even plot with a fair amount of white clover. 4 Adelaide guano 1 cwt., basic super 1 cwt., steamed bonedust 1 cwt. per acre (applied 29/7/21) . 33 3 3 5 Basic slag i| cwt., superphosphate x£ cwt. per acre 39 0 9 Best plot for white clover. 6 Superphosphate 3 cwt. (applied' August, 1921), and carbonate of lime 1 ton (applied June, 1921) per acre 35 2 1 Fair amount of white clover. Most Lotus and suckling-clover. One of few plots showing ryegrass.

The following table was prepared after the hay was weighed on 17th December last. The area of each plot is 3/10 acre.