10 Feb., 1916.] Potato Experimental Fields, 1915-16. 107 



POTATO EXPERIMENTAL FIELDS, 19L5-16. 



Jl// ./. T. Ramsay, Potato Expert. 



Experiments in the cultivation of potatoes are being continued this 

 season at Leongatha, Koo-wee-rup, and Portland. The ai-eas on which 

 the work is being carried on were cho&en, firstly, because the soils were 

 suited to potato production; and, secondly, because they are typical of 

 large areas of land within the State, so that the results obtained will be 

 widely applicable. 



The accompanying plans show the details of the experiments and 

 demonstrations. 



Leongatha. 



At Leongatha 5^ acres in all have been planted, which have been 

 divided into sections as follows : — Section 1 is designed to test the 

 efl'ectiveness of eleven different manurial treatments, ranging from a 

 moderate dressing of 3 cwt. of superphosphate per acre to 15 cwt. per 

 acre of a compound, comprised of phosphatic, potassic, and nitrogenous 

 manures, in order that the most profitable mixture and rate per acre 

 may be determined. On this section thus treated, manurially, there have 

 been planted ripe and immature seed of three different varieties suited 

 to the district, namely. Factors, Sutton's Abundance, and Up-to-Date. 

 All of these did fairly vs^ell in the district last year in spite of the dry 

 season. 



Section 2 is given to testing the efficiency as a preventive of disease 

 of the use of dipping and spraying solutions. Tlie portions ot tins sec- 

 tion are seeded wilIi potatoes which were {a) dipped straight away when 

 dug last April; (h) dipped in November, just before planting; and (c) 

 not treated with dipping solution. Fractions of each of these 

 will be sprayed during the growing period, " so that at the end 

 or the season the results obtainable will range from seed wdiich was abso- 

 lutely untreated, as far as disease prevention is concerned, to that whicn 

 was dipped only, sprayed only, and thence to plots which were as fully 

 guarded from disease as is practicable by dipping and spraying treat- 

 ments. The dipping solution used was made from corrosive sublimate 

 at the rate of 1 oz. to 6 gallons of water, and seed treated with this 

 solution was immersed for two hours, and then thoroughly drained and 

 dried before planting. Spraying during the season will be done with a 

 solution of copper and soda mixed in the proportions of 2 lbs. copi^er 

 sulphate and 2^ lbs. washing soda to 10 gallons of water. 



Section 3 is devoted to testing the best depth at which to plant sets, 

 a question which is the cause of much argument at the present time 

 amongst growers, because of the differences of opinion held on the 

 matter. On this section the tubers have been uniformly spaced in the 

 rows at 18 inches apart, wliile the depths at which tests are being made 

 are 3 inches, 4 inches, 5 inches, 6 inches, 7 inches, and 8 inches. 



Section 4 is carried out to determine the most economical spacing at 

 which tubers should be set, and j)lanting has l>een done at 12 inches, 

 15 inclies. 18 itiches, and 21 inches, wliile the depth of planting has been 

 kept uniforndy at 4 ^ inches. 



Section 5 will give a demonstration of the value of immature seed, 

 as compared with ri|>e seed, and is cne of the most imjiortant sections, 

 if any distinction can be justly made. Six varieties are being used, 

 these beiiii: Sutton's, Factors, Carman, Early Norther, Black Prince, 



