It is recommended to apply w strip of Apivar to every 5 frames covered with bees. Strips should be placed near the center of the cluster and where the bees found. Having said that if the bulk of the bees (i e 7 frames of bees) n the bottom brood chamber and 3 frames of bees in the top brood chamber, then  2  strips should be placed in the bottom brood chamber and one in the top brood chamber. Apivar has slow activity curve. mites  drop is low in the first 3 days and builds up from 4-9 days and will continue based on mites emerging with bees. Apivar made by Arysta/ France does not volatile. Strips should be stored as mentioned on the label. These Apivar/Arysta strips are the ones registered and used in Canada and I did too many studies on them.
Our research showed that you don't get much activities if strips are in the top brood box and bees in the bottom box. It makes sense.
As Bob said, if no mites, no drop.

Medhat Nasr
Alberta canada 2.5 hrs North of Allen.
This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the system manager. This message contains confidential information and is intended only for the individual named. If you are not the named addressee you should not disseminate, distribute or copy this e-mail.

             ***********************************************
The BEE-L mailing list is powered by L-Soft's renowned
LISTSERV(R) list management software.  For more information, go to:
http://www.lsoft.com/LISTSERV-powered.html

Guidelines for posting to BEE-L can be found at:
http://honeybeeworld.com/bee-l/guidelines.htm