A surprising 90^ o£ the growers used a chemical thinner on 

 Delicious. This certainly would indicate that at least in 

 some years, lack o£ fruitfulness is not a problem as frequently 

 mentioned with Delicious in many fruit growing areas of the 

 United States. 



Of the growers using chemical thinners on Delicious: 85% used 

 carbaryl, 9% used NAA, and 61 used carbaryl or NAA , or carbaryl 

 or NAAm. We do not recommend the use of NAA or NAAm on Deli- 

 cious because following their use many small seedless fruits 

 may persist on the tree. 



3. Do you apply a growth regulator to prevent pre-harvest drop 

 (yes or no?) If the answer is yes, what material do you use 

 on Mcintosh, on Delicious? 



As expected most growers (981) used a growth regulator to pre- 

 vent pre-harvest drop of Mcintosh. Of them, 93% used Alar-85* 

 and 7% used NAA. Only 51% of the growers used a growth regulator 

 to prevent pre-harvest drop of Delicious, and of these, 93% 

 used Alar-85*, 3% used 2 , 4 , 5- trichlorophenoxypropionic acid 

 (2,4,5-TP), and 3% used either Alar-85* or 2,4,5-TP. 



We caution growers to avoid rates in excess of 1.5 lbs. of 

 Alar-85* per acre (assuming 300 gallons/A of dilute spray) on 

 Delicious because of possible fruit size suppression and fruit 

 flattening. On trees where fruit size may be small, 2,4,5-TP 

 is suggested rather than Alar-85*. At 20 ppm, 2,4,5-TP will 

 reduce rate of drop for about 4 weeks. This growth regulator 

 is generally applied in early October before frost injures the 

 leaves . 



4. Have you used Promalin* within the last 2 years to elongate 

 Delicious (yes or no)? Do you plan to use Promalin* next spring 

 (yes or no) ? 



Forty percent of the growers indicated that they had used Promalin* 

 on Delicious. Of the growers that have used Promalin* 64% stated 

 that they plan to use this growth regulator again. Nine percent 

 of the growers who have not used Promalin* plan to use it, weather 

 permitting. 



The author considers the results of Promalin* to be very unpre- 

 dictable under Massachusetts conditions. It can increase the 

 typiness of Delicious but frequently the fruit response is slight 

 and this growth regulator has fruit thinning capabilities if 

 misused. 



Trade Name 



