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Table 3. Tlie Influence of Chemical Thinners on Fruit Set and Size of Puritan 

 Apples. 1963. 



Treatment 

 XEer_J.O,0„£al.s_,X 



1. Check 



2, Sevin 1# 



._AEplied_. 

 fF+14 



No. of 

 Trees 



Fruits/cm. 

 of Limb 

 Circumference 



10 

 10 



6.4 

 4.0 



Avg, Fruit 

 Diameter 

 (I nches) 



2.53 

 2.58 



■'-Fruit size measurements made August 6, 1963 (30 fruits at random per tree) about 

 1 week before harvest commenced. 



It is apparent from Table 3 that these Puritan did not need to be thinned with 

 Sevin at all to obtain suitable fruit size. Similar results over the past few 

 years and comparable observations by growers have convinced us that Puritan may 

 be the rare early apple which doesn't often overset. Of course, all trees of this 

 variety arc relatively young and oversetting may become a problem as they get older. 

 However, we suggest that young Puritan should not be chemically thinned even where 

 interplanted with other varieties that are suitable cross-pollinizers . NAA and NAD 

 should not be used on Puritan since they are apt to be quite injurious to Puritan 

 foliage and very apt to overthin this variety, ■ 



Unfortunately, Puritan is extremely biennial even though it doesn't overset. 

 We are now in the process of trying some other treatments that we hope will tend 

 to induce annual flowering on this and other hard-to-make-annual varieties. 



Details concerning chemical thinning of various apple varieties will be 

 available in our Special Circular No. 189 sometime in April, as usual. 



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