Botany picture #44: Taxodium

Further to our trip to Lake Ginninderra last Sunday, this is a nice picture of cypress knees, parts of the root system of swamp trees that stick out above the ground. It is frequently assumed that they help supply the roots in the waterlogged soil inhabited by these trees with oxygen, but apparently there is still some doubt about their true function.

And this is the tree to which the roots belong, a Taxodium or swamp cypress from North America, here grown as an ornamental tree in an Australian park otherwise well stocked with native Casuarina and Eucalyptus. Taxodium and a few related genera of conifers once formed their own small family but have recently been sunk into the large Cupressaceae family (cypresses, junipers, Thuja and relatives).