Tree throw
Encyclopedia
A tree throw or tree hole is a bowl-shaped cavity or depression created in the subsoil
by a tree
.
They are formed either by the long term presence and growth of tree roots or when a large tree is blown over or has its stump pulled out which tears out a quantity of soil along with the roots. The resultant hole will often slowly fill with organic material and can be identified during archaeological fieldwork.
Fresh tree throws also provide a degree of shelter amongst the roots for animals. Some also contain evidence of prehistoric human activity such as flint tools suggesting that they were sometimes used by people in the distant past.
Tree throws expose humus-poor, mineral
-rich soil and often collect moisture and fallen leaves which soon form a thick organic layer and so are able to nurture certain types of organisms.
Pits from tree throws, together with mounds from decaying fallen trees, are part of the characteristic topography of old growth forest
.
Subsoil
Subsoil, or substrata, is the layer of soil under the topsoil on the surface of the ground. The subsoil may include substances such as clay and/or sand that has only been partially broken down by air, sunlight, water, wind etc., to produce true soil...
by a tree
Tree
A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to...
.
They are formed either by the long term presence and growth of tree roots or when a large tree is blown over or has its stump pulled out which tears out a quantity of soil along with the roots. The resultant hole will often slowly fill with organic material and can be identified during archaeological fieldwork.
Fresh tree throws also provide a degree of shelter amongst the roots for animals. Some also contain evidence of prehistoric human activity such as flint tools suggesting that they were sometimes used by people in the distant past.
Tree throws expose humus-poor, mineral
Mineral
A mineral is a naturally occurring solid chemical substance formed through biogeochemical processes, having characteristic chemical composition, highly ordered atomic structure, and specific physical properties. By comparison, a rock is an aggregate of minerals and/or mineraloids and does not...
-rich soil and often collect moisture and fallen leaves which soon form a thick organic layer and so are able to nurture certain types of organisms.
Pits from tree throws, together with mounds from decaying fallen trees, are part of the characteristic topography of old growth forest
Old growth forest
An old-growth forest is a forest that has attained great age , and thereby exhibits unique ecological features. An old growth forest has also usually reached a climax community...
.
See also
- Reverse stratigraphyReverse stratigraphyReverse stratigraphy is the result of a process whereby one sediment is unearthed by human or natural actions and moved elsewhere, whereby the latest material will be deposited on the bottom of the new sediment, and progressively earlier material will be deposited higher and higher in the...
- Nest boxNest boxA nest box, also spelled nestbox is a man-made box provided for animals to nest in. Nest boxes are most frequently utilized for wild and domesticated birds, in which case they are also called birdhouses, but some mammalian species may also use them. Birdhouses are the most common types of nest...
- Snag
- Tree hollowTree hollowA tree hollow or tree hole is a semi-enclosed cavity which has naturally formed in the trunk or branch of a tree. These are predominantly found in old trees, whether living or not...
- StonehengeStonehengeStonehenge is a prehistoric monument located in the English county of Wiltshire, about west of Amesbury and north of Salisbury. One of the most famous sites in the world, Stonehenge is composed of a circular setting of large standing stones set within earthworks...