Simazine Rate and Eucalyptus globulus Withholding Period

AIM:
To determine the appropriate withholding period for planting Eucalyptus globulus following application simazine herbicide.

CONCLUSIONS:
• Increasing simazine rates or decreasing withholding periods had no statistical significant negative impact on total stem volume production.
• There was an observable initial phytotoxic impact on tree health from the pre plant application of simazine. The severity of the phytotoxic impact increased with the increase in application rate.
• Stocking losses due to sand blasting, drought and rabbit damage during the first six months of the trials establishment had a greater impact on total stem production than the phytotoxic impacts of simazine.

RECOMMENDATIONS:
• The current simazine label instruction of allowing a minimum of 2 weeks from chemical application to tree planting of eucalypt species is followed.