-20- 



USE OF PROMALIN TO INCREASE BRANCHING OF YOUNG TREES 



Duane W. Greene 

 Department of Plant and Soil Sciences 



Abbott Laboratories has been granted final label registration 

 for Promalin to improve branching on apple trees. There are sever- 

 al varieties and strains such as Macoun, Empire, Macspur and other 

 spur-types that branch sparsely, which limits their productive cap- 

 acity. Promalin*may increase lateral bud break and total shoot 

 growth per tree and improve branch angles on non-bearing trees. 

 Promalin may also reduce the potential return bloom for the season 

 following application. Therefore, Promalin is primarily recommended 

 for non-bearing trees to enhance early scaffold branch growth and 

 development and to provide a better tree framework. 



Application Methods and Rates Suggested on Label 



Foliar sprays . Use one-half (0.50) to one CI) pint of Promalin 

 per 5 gallons of spray solution to attain a concentration of 250 

 ppm of Promalin in the final spray solution. Wetting, spray cover- 

 age and subsequent absorption can be improved by the addition of a 

 wetting agent such as Buffer-X, Tween 20, or Glyodin. The wetting 

 agent should be added to the spray tank before Promalin. The final 

 spray should not be alkaline. If you have reason to suspect that 

 your water may be alkaline, then it may be advisable to add a buffer 

 such as Sorba Spray, vinegar or a buffered surfactant such as 

 Buffer-X. 



Latex applications . Use one-third (0.33) pint of Promalin per one 

 (1) pint of interior flat latex paint to attain a concentration of 

 7500 ppm. Mix thoroughly. A buffered wetting agent such as Buffer-X 

 or Tween-20 should be added to the tank mix at a rate of 0.5 to 1.01 

 prior to the addition of the Promalin. This practice will improve 

 the solubility of Promalin in the latex paint and will also improve 

 wetting and absorption through the waxy layers on the bark surfaces. 



Research in Massachusetts showed that sometimes too many branches 

 are stimulated following a Promalin application. This is especially 

 true when 500 ppm Promalin is used on very responsive varieties, such 

 as Macspur and Empire, at a time when growth is rapid and environmental 

 conditions favor foliar penetration. This situation can be overcome 

 by: 1) using lower rates of Promalin; 2) using the high rate of 

 Promalin, then returning about 3-4 weeks after application and remov- 

 ing the unwanted developing shoots. 



Method of Application Suggested on Label 



Foliar sprays . Uniformly apply the Promalin spray mixture with a 

 pressurized hand sprayer, hand gun attachment to an airblast sprayer, 

 or an airblast sprayer to thoroughly wet the bark and foliage sur- 

 faces. Do not apply to point of runoff. It is suggested that 



"S 



Trade name 



