Smaller mesh sizes, such as 30×30 holes/square inch, are more effective at keeping pollen out of your gutters. If pollen is a high concern for your gutters, we recommend choosing a GutterglovePro gutter guard that is made with 30-mesh. If pollen ever did clog an area of the micro-mesh, your gutter guard can be unclogged with a gutter cleaning brush, like The Gutter Guard Brush, found here.