2. Old and Large Trees
Age and size are characteristics of trees that are long-living and tall. Here are some examples:
The verified oldest measured ages for coniferous trees are (according to the Gymnosperm Database): The Bristlecone Pine (Pinus longaeva) in Nevada - 4844 years. Alerce (Fitzroya cupressoides) - 3622 years and the Giant Sequoia (Sequoiadendron giganteu) - 3266 years. Other species suspected of reaching exceptional age include the European Yew (Taxus baccata) (probably over 3000 years) and the Western Redcedar (Thuja plicata).
The oldest verified age for an angiosperm (broadleaved) tree is 2293 years for the Sri Maha Bodhi Sacred Fig (Ficus religiosa) which was planted in 288 BC in Sri Lanka. This is also the oldest human-planted tree with a known planting date.
The height of the tallest trees in the world has been the subject of considerable dispute and much exaggeration. Historical claims of trees as high as 130 m or 150 m, are now largely regarded as unreliable.
The Coast Redwood (Sequoia sempervirens) has been recorded to have reached 113 m in California (again according to the Gymnosperm Database). The highest living tree listed in the U.S. National Register in 2002 is the Redwood at 98 m (1998).
In order to define the volume of a tree one basically needs to know the height and diameter. The latter is obtained by dividing the measured circumference by π. (it assumes the trunk is circular in cross-section) This is cited as dbh (diameter at breast height- 1.3 m).
The largest trees in total volume are those that are both tall and of large diameter, with particularly large diameter around the trunk. This measurement becomes very complex if branch volume is to be included as well (root volume is not included).
The top species measured so far are (according to the Gymnosperm Database): (1) Giant Sequoia (Sequoiadendron giganteum) - 1489 m³, (2) General Sherman, Coast Redwood (Sequoia sempervirens) - 1045 m³, (3) Del Norte Titan tree, Western Redcedar (Thuja plicata) - 500 m³.
In addition to age and height, trees also show a wide variety of canopy structure, leaf type and shape (important in recognising tree species), bark characteristics, and reproductive structures (i.e., flowers, fruits and cones).