August, 19: On Thursday morning, hail and sleet were falling on the high ground of the Invermay Experimental and Research Station at North Taieri. The following morning superphosphate came sprinkling down from the sky during what was the first aerial top-dressing demonstration held anywhere in the district.
The work was being carried out by a private company. There was a large gathering of interested people to watch the demonstration, including Department of Agriculture officials, fertiliser and farmer interests, officials of the company and a group of scholars from the Agricultural College of the Mosgiel District High School.
Those present saw the aerial sowing of fertiliser under perfect conditions at the rate of five tons an hour.
Operating from a height of about 75ft, the pilot, Mr R. Bush, covered an area of rising second-class hill country.
The machine used, a Tiger Moth, operated from the station's cowshed paddock alongside the detour road to Wingatui from Black bridge.
A truck, with a large outrigger in front and hydraulically operated, loaded the machine from a hopper attached to the end of the outrigger.
Into this hopper were poured two bags of superphosphate, a total of 374lb. The truck then went forward, and by means of a canvas shute, emptied the load into the Tiger Moth.
The machine was away in a flash on each run and distributed its load over a 22-yard span for a distance of 11 chains, an equivalent of one acre and one-tenth per run.
To reach the spreading ground, the distance was approximately three-quarters of a mile. The machine covered the distance, spread the fertiliser, and returned to reload in an average of 2min 30sec, and its average time on the ground between trips was 35sec.
Sowing at this rate with clocklike precision, the work went on for two hours, the machine working further up the hill until its later distribution loads went on to territory beyond the sight of the watchers.
Mr George Holmes, the superintendent of Invermay, welcomed the gathering. The paddock being treated, he said, was beginning to run out, but it was hoped by this method of top-dressing to help bring it back in again.
What was being done now in minutes would, under the normal wheeled method of top-dressing, take hours, he said.
There were thousand of acres of similar types of country in Otago, and the problem was to make them more productive.
They wanted to see the hill country breeding more sheep, for one of their problems was going to be replacement ewes for the flats. He wished the company every success in its work.
Mr P. B. Lynch, an experimentalist from the Department of Agriculture, Wellington, told the gathering that top-dressing from the air had come to stay in the North Island.
There the work had been carried out with converted bombers, carrying two tons of fertiliser, but this meant inter-communication between ground and machine when out in the hills, and it was now found that with a lighter load and a quick turn-round, the work of spreading by a small plane was as good as by a big one.
For perfect precision work, he thought, a granulated superphosphate was required.
Mr E. R. Curtis, the chairman of the company, who is a runholder in the Patearoa district, describing the work of the Tiger Moth, said it could average 400 acres a day.
Under good conditions, 1000 acres of farmland could be adequately top-dressed in two days and a-half.