10- 



Use on early maturing varieties . Ethephon is a very useful tool 

 on early varieties. In general, a single application applied 

 7-10 days before normal harvest at 1/2 pint per 100 gallons of 

 water will increase red color development within 4-5 days. 



Ethephon has been used extensively on Early Mcintosh, Puritan 

 and Milton varities by Massachusetts growers with good results. 

 Rate of color development differs from year to year and block to 

 block among orchards. Within a block of trees, the red color gen- 

 erally develops more slowly on the earliest sprayed trees than those 

 sprayed nearer to the normal harvest date. 



This shows that color develops more quickly in some instances 

 than others and that there is no substitute for a careful daily 

 check of trees. Early varieties usually ripen unevenly. Therefore, 

 it may be advisable, for some varieties to make one picking to 

 remove the riper fruit and then apply ethephon. This should help 

 minimize the problem of over-ripe fruit at harvest. Some growers 

 may want to apply ethephon, then pick the ripe fruit that day, or 

 1 or 2 days later. Although the ethephon label does not state a 

 specific interval between application and harvest, the practice of 

 spraying and harvesting within 2 days of application is not recommenc 

 ed. Harvesting all the mature fruit and then applying the ethephon 

 to the remaining fruit on the tree is the preferred practice. Ethe- 

 phon applied alone accelerates fruit drop. Therefore, naphthalene- 

 acetic acid (NAA) should be used with the ethephon to counteract this 

 abscission effect. 



Use on 'Mcintosh ' . Our suggestions are based on 3 time periods for 

 sale of ethephon- treated 'Mcintosh' fruits -- prior to normal harvest 

 time (Labor Day or shortly after), during normal harvest, and after 

 several months of storage (Table 1) . 



The volume of fruits sprayed with ethephon should be based upon 

 anticipated sales during one or more of these sale periods. The 

 harvest of ethephon- treated fruit must not interfere with the timely 

 harvest of fruit for CA since the placement of ethephon- treated fruit 

 in this type of storage is not recommended. Our data and those from 

 a regional experiment involving New York, Maine and Massachusetts, 

 show that ethephon- treated fruit which still are in good condition 

 will store satisfacotrily in CA, but we are concerned that apples 

 not in good condition will be stored. However, if labor difficulties 

 worsen, it may be necessary to extend the harvest season by advancing 

 it through the judicious use of ethephon on CA 'Mcintosh'. 



Fruit to be placed in storage at 32 F must be picked at proper 

 maturity. Fruit to be sold through January 1, should receive no more 

 than 1/4 pint of ethephon per 100 gallons of water and be harvested 

 7-8 days after treatment. Although these fruit should store well 

 until January 1, they may be softer than Alar*- treated fruit. 



'Alar = Alar-85* 



