CHEMICAL CONTROL OF WATER SPROUTS AND ROOT SUCKERS OF APPLES-'^ 



William J. Lord, Joseph Sincuk and 

 Maureen Tumenas 



Department of Plant and Soil Sciences 



Water sprouts are particularly troublesome on standard- type 

 Delicious and following heavy pruning. Generally they are re- 

 moved to maintain tree form and prevent shading. Unfortunately, 

 their removal becomes more time consuming in succeeding seasons 

 because of the proliferation from the stubs created by pruning. 

 Sucker growth from roots of mature seedling trees and in plantings 

 of M.7, M.7A and interstem trees is a serious problem, and diffi- 

 cult to control in Massachusetts. Suckers are costly to remove, 

 increase in number annually, provide mouse cover, and are a haven 

 for insects and diseases. 



Water sprouts and suckers can be controlled with a special 

 formulation of naphthalene acetic acid (NAA) . This formulation 

 is available as Tre-Hold Sprout Inhibitor A112* and is registered 

 for use on bearing apple trees. 



Mixing Directions 



For the control of water sprouts use 10 fluid ounces (2/3 

 pint) of Tre-Hold and make up to a volume of 1 gallon with a 

 combination of water and interior-grade latex paint. The latex 

 paint "marks" the treated areas and makes the mixture more viscous, 

 thus restricting the NAA to the treated area. It has been our 

 experience that at least 4 pints of latex paint should be used 

 in each gallon of treating solution. Be sure to use an interior- 

 grade latex paint and one that does not contain a mildewcide. 

 Do not use oil base or exterior grade latex paint, since they can 

 cause injury. 



For spraying suckers , mix 10 fluid ounces of Tre-Hold with 

 sufficient water to make 1 gallon of spray mixture. Eight gallons 

 of Tre-Hold are required for 100 gallons of spray. The addition 

 of a surfactant or spreader- sticker to the Tre-Hold mixture may 

 increase its effectiveness. 



Application for Control of Water Sprouts 



Prune water sprouts and then apply the Tre-Hold mixture thor- 

 oughly over the cut surfaces. It can be applied with a paint brush 

 or a small compressed air sprayer. We found that a 1-1/2 gallon 

 compressed air sprayer with a 12-foot hose worked well, and that 

 attaching a sponge to the nozzle was useful for swabbing the mixtu 

 on pruning cuts. The treatment can be applied anytime weather 

 permits but before growth starts in the spring. Areas where prun- 

 ing cuts have been made should be covered thoroughly but dripping 

 onto other parts of the tree should be avoided. The Tre-Hold mixture 

 can kill buds. Be sure to follow the label. 



re 



1 



Water sprouts are vigorous shootis arising from any part of the tree 

 above the ground. Suckers are shoots which arise from the roots. 

 Trade name 



