Oct. 2, 1920.] Agricultural Gazette of N.S.W. 699 



Top-dressing Lucerne with Superphosphate* 



EiELD Experiments at Yanco. 



E. B. FURBY, Experimentalist. 



[The Experiment Supervision Committee wishes to point out that the following are the 

 results from the first year's trial only, but in view of the successful use of superphosphate 

 as a top-dressing on lucerne in other districts it has been thought advisable to publish 

 the report.] 



This experiment was set out on the following plan, and the applications of 



superphosphate were made accordingly : — 



Plot 1 ... (Check) Cultivated but not manured. 

 ,, 2 and 3 ... 1 cwt. superphosphate per acre applied in the spring. (8th 



September, 1919). 

 ,, 4 ... ... No cultivation and not manured. 



,, 5 ... (Check) Cultivated but not manured. 



,, 6 and 7 ... 2 cwt. superphosphate per acre applied in tlie spring {8th 



September, 1919). 

 ,, 8 ... (Check) Cultivated but not manured. 

 ,, 9 and 10 ... 1 cwt. superphosphate per acre applied in the autumn (13th 



June, 1919). 

 ,, 11 ... (Check) Cultivated but not manured. 

 ,, 12 and 14 ... 2 cwt. superphosphate per acre applied in the autumn (13th 



June, 1919). 

 ,, 13 .. ... No cultivation and no manure. 



,, 15 ... (Check) Cultivated but not manured. 



The plots each comprised J acre. With the exception of Nos. 4 and 13, 

 all were cultivated as deeply as possible in June, as soon as it was practicable 

 to get on the land after the last cut had been removed, the autumn applica- 

 tion of manure then being applied. No further cultivation was given prior 

 to the spring dressing, which was applied early in September, just as the 

 lucerne was making a fresh start to grow. 



As there was practically no rain in the winter in any quantity, the full 

 benefits of autumn manuring were not fully realised, for the little rain there 

 was did not penetrate to the subsoil, and it was not until artificial watering 

 was commenced in the spring that the ground was thoroughly saturated and 

 the manure made available for plant use. Concerning the spring dressings, 

 no indications were noticed on any of the plots to show that the manure from 

 these had been washed to the lowest end of the plots to cause a better growth 

 there. Any extra vigorous growth in the paddock occurs in isolated places on 

 treated and untreated plots alike, and cannot therefore be attributed to the 

 effects of the superphosphate. 



Since the autumn dressing was made on 13th June only 345 points of rain 

 have been recorded, while altogether eleven irrigations have been made — ■ 

 on the following dates : — 23rd July, 3rd September, 25th October, 25th 

 November, 9th December, 18th December, 10th January, 19th January, 6th 

 February, 26th February, and 8th March. Very hot, windy weather has 

 prevailed throughout the season until latterly, when a cool change occurred, 

 with a coinciding diminution in the rapidity of the growth of the lucerne. 



