biodiversity homepage
click for contacts  

photo by V. Medland

Nikon Coolpix 995

bottle gentian flower closeup.

Gentiana andrewsii, the Bottle or Closed gentian is native to Wisconsin. This late summer flower is usually found in moist wooded areas near streams and ponds. The leaves are lance shaped and the tubular flowers are borne in clusters at the tops of the stems. What is unique about this flower is that, as its common name suggests, it never opens. Inside the bottle, however is a rich supply of nectar and pollen that attracts insects. In order to get inside, it seems, that an insect would have to have a very long tongue or be very tiny. If you press on the flower, though you would notice that the petals are not truly fused and will push apart so any insect that is strong enough could push its way inside. I don't recommend this though because bumble bees and some beetles are large enough to do the same thing. They push their way inside and the petals close behind them as they feed on the nectar inside. If you squeeze the wrong flower you just might get stung by an unhappy bee!

It might seem odd that such a late blooming flower would limit the kinds of pollinators that can reach the pollen. Scientists speculate that by limiting access mostly to bumblebees might ensure better pollination because bumble bees will seek out the same species of flowers as long as nectar supplies are high. So bumble bees are "loyal pollinators", only traveling between gentians delivering pollen, resulting in higher rates of fertilization, while other pollinators like flies might be going from one species to another and therefore not delivering gentian pollen and limiting fertilization and seed production.

Contributed by V. Medland

© 2001-2004 The Cofrin Center for Biodiversity and the University of Wisconsin Green Bay, All Rights Reserved
Last updated on May 9, 2014