For myself I don't have the time it takes to take two brood chambers every
few days to apply MO to the tops of the bars in the brood chambers, so I
came up with this alternative. I take some thick cloth like a towel about an
inch wide and the length of the hive opening staple it so it is about half
way inside the hive on the landing board and apply the MO to it. As the bees
go in and out they get treated and take it into the hive. It is very fast
and the results thus far are as good as applying it to the top bars.