Pre-plant aerial herbicide operations using spray adjuvants to improve their cost-effectiveness and timeliness

Authors: Robyn Gaskin, Kevin Steele, Mark Kimberley
Publication: New Zealand Journal of Forestry, Volume N.Z.J.For. 2013, Issue N.Z.J.For. 58(1) 2013, pp 38-43, May 2013
Publisher: New Zealand Institute of Forestry

Abstract: Abstract Pre-plant control of weeds is essential for survival and growth of forest crops. Aircraft flying time is the biggest cost in control operations, and aerial herbicide programmes are often hindered by poor flying conditions. Anything which reduces essential flying time is likely to benefit forest operations. Organosilicone penetrant adjuvants are routinely used in pre-plant herbicide sprays, but their potential to increase the efficiency of weed control operations has not been fully exploited by the forest industry. Studies carried out in commercial forests in the Bay of Plenty in 2011 and 2012 confirmed that current typical spray application volumes used to apply pre-plant herbicides, for example 100 litres per hectare, could be lowered by up to 50 per cent with no loss of efficacy by increasing the use rate of organosilicone adjuvant. Lowering the application volumes used to apply sprays increases the productivity of aerial spray programmes, and this should result in substantial cost savings. In addition, spray application can be accomplished faster, allowing pilots to exploit ideal flying conditions and forest managers to improve the timeliness of pre-plant spray operations.