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RESULTS OF LEAF Ai'JALYSES OF ORCHARDS IN 1959 



Leaf analysis is regarded as an effective guide to more economical and 

 efficient fertilizer practices and as an aid in diagnosing specific problems 

 in individual orchards. For the last several years, leaf samples have been 

 obtained from problem blocks of trees in a limited number of orchards in this 

 state as an aid in diagnosing nutritional problems. 



In 1959, the Pomology Staff with the cooperation of the Control Service 

 at the University of Massachusetts was in the position to increase the Leaf 

 Analysis Service. County Agents and the ^/riter obtained leaf samples in the 

 orchards that warranted analysis. One hundred and eighty three leaf samples 

 were obtained from 49 orchards and analyzed for nitrogen, potassium, calcium 

 and magnesium. 



The standard mineral contents desired in Mcintosh leaves expressed as 

 per cent dry weight are as follows: nitrogen - 1.80-2.00; calcium - ,90-1.40; 

 potassium - 1.25-1.60; and magnesium - .25-. 40. Analyses of Mcintosh leaf samples 

 from 43 orchards showed nitrogen was above the desired range in 24 orchards and 

 below in 18. Potassium was below the desired range in 14 and magnesium in 34 of 

 the orchards , 



The amount and severity of magnesium deficiency may increase in years which 

 have excessive amounts of rain during the growing season. Our acid soils are low 

 in magnesium and it is readily leached. Also magnesium deficiency is generally mort 

 prevalent and severe in heavy crop years. In 1959, most orchards had large crops 

 and rain in June and July was considerable above normal. In several orchards, visiu 

 symptoms of magnesium deficiency were apparent at time of sampling (July 15 - 

 August 15). By September, this deficiency was observed in many Massachusetts 

 orchards . 



Although potassium was below the desirable range in 14 of the 43 orchards, 

 no deficiency symptoms were noted at time of sampling. The studies conducted by 

 Dr. W, D. Weeks have shown that fruit color of Ifclntosh is associated with the 

 relative amounts of nitrogen and potassium found in the foliage of the trees. The 

 poorest colored fruit was produced by trees which had a high leaf content of 

 nitrogen and low potassium. Trees with a low to medium leaf nitrogen and high 

 leaf potassium produced the highest colored fruit. 



High rates of nitrogen fertilization increase fruit set, increase total 

 yield, decrease fruit color and firmness. Nitrogen can decrease fruit size if 

 it produces an excessive fruit set in a yec.r of heavy bloom. In a talk titled, 

 "Some Business Aspects of Apple Production' presented at the 65th Annual Meeting ' 

 of the Massachusetts Fruit Growers' Association in 1959, Dr. A. B. Burrell of f 

 Cornell stated that "With dessert apples, there is no way to go broke faster than \ 

 by producing high yields of soft, green apples that bruise easily and keep poorly. 

 Discretion in the use of nitrogen is a prime essential for apples that will reach 

 the consumer in good condition". 



The value of leaf analyses as an aid in diagnosing specific problems in 

 individual orchards is shown in the following example. In 1957, a grower requested 

 leaf analyses in a block of Mcintosh trees, 30 years of age. The trees were making 



