Posted on May 27, 2019May 27, 2019 by Robert BrodschneiderBeehold tubes after two weeks… The beehold tubes are used to sample substanced from bees entering the hive. They are placed for two weeks at the hive entrance of colony 1 and 3 with different adaptors (colony 1, colony 3). This is how our beehold tubes look like after they have been two weeks at the flight entrance and thousands of bees passed (left). The right tube is a new one, for comparison! Photo: Kristina Gratzer.