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varietal suggestions 

 M cintosh 



Results of the past 5 years at Amherst show that Mcintosh placed in CA 

 storage will not scald appreciably through April. This statement is predicated 

 on the assumption that the fruit is picked at a flesh firmness of 15 to 17 

 pounds (Magness -Taylor tester with 7/16 inch head), moved from the orchard to 

 storage within 24 hours and cooled to 32°F promptly. CA storage may not always 

 control scald on this variety indefinitely but only delay the time of its 

 appearance. Consequently, some scald may develop on some lots of CA Mclrt osh 

 in May or June which were entirely free from it earlier. It is suggested that 

 DPA, if used at all on Mcintosh, be applied only to those lots of fruit held 

 into May and June. 



Scald on regular cold storage Mcintosh is generally not a problem until 

 after January at which time the bulk of this fruit should have been sold. Our 

 results with DPA or Stop-Scald have not been outstanding for controlling 

 scald on Mcintosh held beyond January in regular cold storage. 



CORTLAND 



In contrast to Mcintosh, CA storage often increases the severity of scald 

 on Cortland in comparison to regular cold storage. Cortland keep.'> exceedingly 

 well in CA (same requirements as Mcintosh) except for scald. Therefore, chemical 

 treatment with scald inhibitors is a necessity if Cortland are to be stored in 

 CA or beyond January 1 in regular cold storage. DPA is distinctly superior to 

 Stop-Scald on this variety. In years when mean temperatures are well above 

 average for 6 weeks or so before harvest, even DPA may not control this disorder 

 adequately. However, DPA may be expected to provide sufficient scald control in 

 most years so that Cortland may be considered for trial in commercial CA rooms. 



DELICIOUS 



Results obtained with this variety indicate that CA may reduce scald on 

 Delicious sometimes but the reduction may not be great enough to eliminate the 

 need for scald control chemicals in some years. This variety is so valuable 

 that DPA is suggested for fruit (particularly the early picked, less mature 

 fruit) placed in CA or to be stored beyond January 1 in regular cold storage. 



ROME 



During the past two seasons CA storage alone has provided commercial scald 

 control on the Romes harvested after October 10. However, DPA is suggested at 

 1000 ppm. (1 pound of the 837, or 1.5 pounds of the 557. formulation) as a 

 preharvest treatment (since 2000 ppm. may occasionally cause some fruit injury) 

 to Romes held in regular cold storage beyond January regardless of when they 

 were picked. Stop-Scald is probably more suitable than DPA as a post-harvest 

 treatment for Rome since it controls scald well and is less apt to injure the 

 fruit than DPA. Work from other areas indicate that the suggestions given for 

 the chemical treatm ent of ^ome appl y equally well to Baldwin . 



F. W. Southwick 



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