196 maine; agricuivtural e^xperiment station. i905. 



The; Fisher Formula. 



In response to a demand for definite information as to the 

 merits of a highly nitrogenous fertiHzer made after what is 

 known as the " Fisher formula," and used quite extensively in 

 some parts of the State, a comparison of this fertilizer with one 

 commonly recommended by the writer for orchard purposes has 

 been undertaken. 



Briefly stated, the Fisher formula — so called because first 

 suggested by Dr. Fisher of Massachusetts — is composed of about 

 8.6 per cent nitrogen, 3.3 per cent phosphoric acid and 11. 9 

 per cent of potash, being made up as follows : Nitrate of soda, 

 350 lbs; sulphate of ammonia, 150 lbs; sulphate of potash, 

 230 lbs ; acid phosphate, 200 lbs ; kieserite, 50 lb. " All 

 to be thoroughly mixed and sown on the surface under 

 the tree out a little further than the limbs extend, at the rate of 

 ten pounds to a medium sized tree, from the first to the tenth of 

 May, or as soon as the blossom buds begin to open." 



Unquestionably this fertilizer produces a most vigorous 

 growth, resulting in large, though not always well colored fruit, 

 and on uncultivated land it is regarded with favor by many 

 growers. For use in connection with the thorough cultivation 

 now recommended, however, the percentage of nitrogen is too 

 high for the best results. 



The Station formula contains about 3 per cent nitrogen, 5^ 

 per cent phosphoric acid and 8 per cent potash, being made up 

 as follows: 200 lbs nitrate of soda; 75 fbs sulphate of ammo- 

 nia ; 225 lbs muriate of potash ; 500 lbs acid phosphate. 



The cost of this fertilizer is about $16 per 1,000 pounds; that 

 of Fisher fertilizer about $21 per 1,000 pounds for the materials 

 alone. 



Twenty Baldwin and five Tolman trees are being used for the 

 specific test of each of these formulas. The Baldwins are kept 

 under cultivation ; the Tolmans are in sod. The work has been 

 in progress for two seasons, which time is of course not suffi- 

 cient to warrant conclusions. It may be said, however, that both 

 lots of trees have responded freely to the treatment, and yielded a 

 good crop of fruit this year. The Baldwins were in an exhausted 

 condition when the work was commenced, but all are now 

 making a remarkably strong, vigorous growth, and promise 



