Trees can live thousands of years if they aren't cut down for wood or to clear the land, and no matter how many trees we plant, we cannot replenish the supply of thousand-year-old trees. As useful as young trees are, a tree near the end of its life is uniquely essential to the world's biodiversity. An example is Big Belly Oak, a 1100-year-old tree in England's Savernake Forest.
While an ancient tree like this is impressive at a distance, take a look inside and you will see something even more intriguing.
Oak polypore fungi and stag beetle larvae feast on the dead heartwood, adult stag beetles sup the sugary liquid from the "sap runs", the living layers of wood which transport water and minerals throughout the tree. Hover flies lay eggs in water-filled rot holes, rat-tailed maggots devour leaf litter and violet click beetles eat up wood mould that is rich with faeces and other remains, accumulating over a century. Knothole moss and pox lichen cling to the bark in rainwater channels. Barbastelle bats hibernate in crevices and under loose bark. Woodpeckers and nuthatch enlarge holes for nesting, while owls, kestrels, marsh tit and tree-creeper move in to ready-made cavities.
These rich pockets of life are a secret world, a diverse habitat teeming with insects, fungi, lichen, birds and bats. The ancients of our forests provide essential food and shelter for more than 2,000 of the UK's invertebrates species. In Savernake Forest alone, these trees are home to nearly 120 species of lichen, more than 500 species of fungi, and other important wildlife such as the elusive white-letter hairstreak butterflies.
Such trees fill environmental niches around the world. But while we can't plant ancient trees, conservationists from several different organizations have developed techniques for artificially aging trees for the purpose of supporting these other species. At least one technique ages a tree 100 years in just two years time. Read how this may work to recreate ancient natural ecosystems at BBC Future. -via TYWKIWDBI