72 



the ground, taking care not to get it too close to the tree trunk 

 where there are few absorbent roots, and extending the applications 

 well out beyond the spread of the branches. To conform more 

 closely with the distribution of feeding roots, the rate of application 

 is made heaviest in the central part of this area, or in general it 

 is applied heaviest under the outer two-thirds of the spread of the 

 branches. This fertilization may either be left on the surface to 

 be washed in by the rains or it may be harrowed or lightly plowed 

 into the soil. With all this done, it should be remembered that 

 the fertilizer applied in any given season can hardly materially 

 affect the yield in that year, since the fruit buds are formed in 

 the latter part of the preceding season. Important results therefore, 

 should not be expected before the following season, at the earliest, 

 and as indicated in some of our experiments, they may not appear 

 until considerably later and still prove of value. 



Determining the Actual Needs of an Orchard. 



The general fertilizer formula indicated above is for use only 

 until the exact needs of the particular orchard can be determined. 

 In other words, it is intended to meet only immediate demands. 

 If in the meantime one washes really to answer the question of how 

 to fertilize his own orchard, he can do so by following the plan out- 

 lined in Table VII. This plan is especially adapted to the needs of 

 commercial orchardists and to "community" tests on the part of the 

 smaller growers. 



Table VII. Plan for Local Orchard-Fertilizer Test. 



(Pounds for a Mature Tree in Bearing.) 



1 Check. Untreated. 



2 Niter, 2^ lb. ; D. Blood, 31^ lb. ; Ac. Phos. 10 lb. 



3 Niter, 2^ lb.; D. Blood, 3^^ lb.; Potash 2 lb. 



4 Acid Phos. 10 lb. ; Potash 2 lb. 



5 Check. 



6 Niter,*2i^ lb.; D. Blood, 3^ lb.; Ac. Phos. 10 lb.; Potash 2 lb. 



7 Same as VI, plus Lime, 12 to 25 lb. 



8 Manure, 400 lb. 



9 Check. 



This plan should be located in a typical part of the orchard, 

 and should include not less than five average trees of the same 

 variety and age, in each plot. All the trees should be labeled and 

 carefully measured at a fixed point on the trunk, and definite 

 records of their growth and yields should be kept for at least three 

 years. Frequently good indications of the orchard's needs may be 

 obtained in less time than this, as is shown above in the Johnston 

 and Brown orchards, but at least this amount of time should be al- 

 lowed and more should be used when necessary. 



The same time and methods of application and other precau- 

 tions should be followed as described above. The materials are 



