Mix 1 part filtered pure lemon juice with 2 parts brown sugar. Add to water bath to max 35 degrees for 2 hours. Add 3 tea spoons of salt per liter of ready cooled lemon sugar syrup. Add 30 drops of tea tree oil per liter of syrup. Give 100-150 ml per hive, 2 times per month.
Systemic or contact mode of action.
https://www.youtube.com/watch?v=D5Usm8Axegk

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