OBSERVATIONS ON THE USE OF A HIGH PRESSURE TREE INJECTION SYSTEM

Summary

In June 1989 sessile oak (Quercus petraea Mattuschka Lieblein), sycamore (Acer pseudoplatanus L.), ash (Fraxinus excelsior L.), red oak (Q. borealis Michx.), birch (Betula pendula Roth.), sweet chestnut (Castanea sativa Mill) and Norway maple (Acer platanoides L.) were injected at 16 bar pressure with water, nutrient solution and a range of concentrations of thiabendazole hypophosphite. Injection times for 70 ml ranged greatly from 17 sec in one sycamore to 212 minutes in one sweet chestnut. Crown damage was normally minimal. Damage to the bark around the injection holes was often very serious.