Apiguard is a slow-release thymol gel - a natural treatment that has proven to be highly effective against varroa mites. This easy-to-use treatment boasts an efficacy rate of between 85% and 95%, with an impressive overall average of 93% even after countless treatments. It promotes hygienic behavior among honey bees, helping to prevent a wide range of related issues. When To Use: To achieve the best results, use this method in the summer, just after the honey flow. Place two 50-gram treatment trays per hive with a 14-day interval between them. This works best when bees are active, and maximum daily temperatures range between 60 and 105 degrees Fahrenheit. How to Use Apiguard: Place the dosing tray or pad centrally on the top of the brood frames gel side up. (Be sure to allow at least 1/4 inches of spacing between the top of the tray and the cover using spacer boards or empty supers as needed.) Apply the second dose 14 days after the first. (Screened bottom boards should be closed while Apiguard is being applied.) *Please note that we can only ship to the United States, where Apiguard is registered and approved. California requires a Grower's ID, which is issued by the Agriculture Commissioner. It doesn't require any testing by the individual and is available to everyone. Please include it in the comments with your order. For more information on Apiguard please visit http://www.vita-europe.com/products/apiguard/