- 27 - 



Rogers/M. 7A. In the original model Rogers/M.7A was selected only in year 

 6 for 0.1 acres. When the number of pickers increased to 9 in year 11 for 

 harvest periods 3 and 4, 1.5 acres of Rogers/M. 7A was selected for planting in 

 year 1. However, if the number of pickers was greater than for the same 

 harvest period, planting Marshall/M.26 was more profitable. Acreage of 

 Rogers/M. 7A planted during year 3 increased when harvest labor increased 

 during year 20. 



Also, selection of Rogers/M. 7A was sensitive to cooling capacity. 

 Increasing cooling to 11,000 bu per 3-day period during year 20 stimulated 

 approximately 3 acres of Rogers/M. 7A to be planted in year 8. This resulted in 

 a reducition of Marshall/M.26 acreage from !J acres to about 2 acres in year 8. 

 Rogers/M. 7A replaced 1.4 acres of Marsiiall/M.26 in year 9 for the same reason. 



Hogers/M. 7A's picking schedule is more similar to Marshal l/OARl than to 

 Marshall/M.26. The bulk of the crops is harvested during the same 2 weeks, 

 but harvestinjf of Marshall/OARl extends about one half week past that of 

 Rogers/M. 7A. However, as more labor and cooling capacity become available 

 Rogers/M. 7A acreage increases while that of Marshall/OARl df'creases, because 

 Rogers/M. 7A begins bearing earlier and reaches full production sooner. 



Marshall/M.7A. Because of earlier coloring Marshall/M.7A has a longer 

 potential harvest period than Rogers/M.7A. However, its harvest period 

 coincides with that of Marshall/M.26, but the latter has a more efficient use of 

 harvest labor. Therefore, in most cases, Marshall/M.26 was chosen rather than 

 Marshall/M. 7A. In fact, Marshall/M.7A never was selected until the 10th 

 planting year. 



Marshall/OARl. OARl is attractive because; it may delay fruit ripening. 

 Extending the harvest season places demands on resources at times when other 

 strains place less or no demand on harvest labor md cooling capacity. It is 

 the one strain requiring harvesting in period 8, and it co(ni>etes only with 

 Rogers/M. 7A during period 7. In all rnodels, somi- .b^reage of Marshall/OARl 

 was selected for planting, because it comple nents other strains as an aid in 

 expanding harvest from 2 vveeks to 4 w;.'cks and provides more efficient use of 

 labor and cooling capacity. 



CONCLUSIONS 



It should be remenberid tliat the results of this study were specific to tiie 

 50-acre rejuvenated orchard described by a given set of conditions. Five acres 

 of the orchard was replanted yearly for 10 years. The research used the 

 methodology of multi-period linear programming to determine the number of 

 acres of 4 different Mcintosh strain-i-ootstock combiiations that should 

 comprise the replanted acres each year. The objective of planting a mix that 

 generates the greatest profit over the 20 year period was (^rjustraincd by the 

 amount of storage, labor, and cooling capacity available during harvest. 



Given the limits, Marshall on M.26 composed 66 to 72% of the 50 acres 

 replanted in each of the alternative >nodels which used varying levels of harvest 

 labor ind cooling capacity. Marshall/M.26 requires more labor and mat trials at 

 planting time becau-;c; the trees may requin; staking and may require more 



