plication of NAA is effective for only 7-10 days. Therefore, its 

 use may involve 2 applications of NAA and the risk of unfavorable 

 weather which may delay the second application or picking. The 

 2,4,5-TP may cause more ripening than NAA, but it does eliminate 

 the chance of excessive fruit loss following an ethephon applica- 

 tion. 



Basically, there are 3 time periods for sale of ethephon- 

 treated Mcintosh f rui ts--prior to normal harvest time, during nor- 

 mal harvest, and from storage. 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 fruits must 

 not interfere with the timely harvest of fruits for CA storage since 

 at present the placement of ethephon-treated fruits in this type of 

 storage is not recommended. Although our data shows that ethephon- 

 treated fruit which still are in good condition will store satis- 

 factorily in CA, we are concerned that apples not in good condition 

 will be stored. 



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

 maturity. Fruits to be sold through January 1 should receive no 

 more than 1/4 pint of ethephon per 100 gallons 

 1) and be harvested 7-10 days after treatment, 

 fruits should store well until January 1, they 

 Alar-treated fruits. 



of water (See Table 



Although these 

 may be softer than 



Suggestions for Use 



In the table below are our suggestions for ethephon use. Eth- 

 ephon should prove beneficial if used properly. 



Table 1. Suggested use of ethephon for promoting uniform ripening 

 and red coloring on apple trees 



Purpose 



Compound, timing and rate 



Early varieties 

 To promote uniform 

 ripening and red coloring 



Ethephon - 7-10 days prior to normal 

 harvest - 1/2 pt/100 gals plus NAA - 

 same timing as ethephon spray 10- 

 20 ppm 



Mcintosh 

 Sales prior to 

 normal harvest 



Alar-85* - mid July - 1 lb/100 gals 



plus 

 ethephon - 2 to 3 weeks prior to nor- 

 mal harvest - 1 pint/100 gals 



plus 

 2,4,5-TP - same timing as ethephon 

 spray - 10-20 PDm. 



