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Table 1. Soil pH and lime requirements (approximate values) 



Initial Soil texture 



soil pH Sands Sandy loams Loams ^^ silty loams Silty clay loam 



12.0 



10.0 



5.0 



2.5 



1.0 



Actual quantity of lime needed varies with the equivalent neu- 

 tralizing value of the limestone used. High-magnesium (Mg) lime- 

 stones usually have greater neutralizing value than low-Mg limestones. 

 Applications of over 2 to 3 tons per acre should be m.ade as split 

 applications to established orchards. During preplant soil prepar- 

 ation, part of the lime can be applied and worked in before plowing 

 the soil and applying and working in the remainder. 



Soil test results for potassium (K) , calcium [Ca) , and magnesium 

 (Mg) are helpful in identifying potential problems especially 

 during site preparation. The amounts of these elements tliat should 

 be applied varies with soil texture, exchange capacity and initial 

 quantities present. In general, these should be built up to high 

 or very-high levels before the orchard is planted. In most Eastern 

 New York orchard soils this means 200 lbs . or more of K (over 150 

 lbs. in some of the heavier clayey soils); and 200 lbs. or more of 

 Mg per acre. Ca levels should approximate 2500 lbs. per acre. 

 Since not all soils have the exchange capacity to hold these quan- 

 tities it is best to start with a soil test. 



P is often overapplied in apple orchards. An initial application 

 of 100 to 120 lbs. of PtOt per acre during soil preparation, combined 

 with correction of soil pH , should be sufficient to provide adequate 

 amounts of P for a number of years. P requirements of apple trees 

 are relatively low (approximately 8 to 10 pounds removed per year 

 in the fruit). No clear-cut beneficial effect of increased P levels 

 has been shown on tree growth, flesh quality or keeping quality of 

 the fruit as long as leaf samples contain at least 0.08 to 0.16% 

 P. On the other hand, excessive rates of P application may pre- 

 cipitate zinc (Zn) or copper (Cu) as insoluble phosphates and pro- 

 duce deficiencies. It is suggested that the initial broadcast 

 application of P in preplant soil preparation may be supplemented 

 with a high P starter solution applied to the newly set tree to 

 possibly help tree root development and that further application of 

 phosphates be eliminated unless leaf samples of P fall below 0.08%. 



