Cladoptosis (

Ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic pe ...

"branch", "falling" oun sometimes pronounced with the p silent) is the regular shedding of

branch A branch, sometimes called a ramus in botany, is a woody structural member connected to the central trunk of a tree (or sometimes a shrub). Large branches are known as boughs and small branches are known as twigs. The term '' twig'' usuall ...

es. It is the counterpart for branches of the familiar process of regular leaf shedding by

deciduous trees In the fields of horticulture and Botany, the term ''deciduous'' () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves, usually in the autumn; to the shedding of petals, afte ...

. As in leaf shedding, an

abscission Abscission () is the shedding of various parts of an organism, such as a plant dropping a leaf, fruit, flower, or seed. In zoology, abscission is the intentional shedding of a body part, such as the shedding of a claw, husk, or the autotomy of a ...

layer forms, and the branch is shed cleanly.

Functions of cladoptosis

Cladoptosis is thought to have three possible functions: self-pruning (i.e. programmed

plant senescence Plant senescence is the process of aging in plants. Plants have both stress-induced and age-related developmental aging. Chlorophyll degradation during leaf senescence reveals the carotenoids, such as anthocyanin and xanthophylls, which are the c ...

), drought response (characteristic of

xerophyte A xerophyte (from Ancient Greek language, Greek ξηρός ''xeros'' 'dry' + φυτόν ''phuton'' 'plant') is a species of plant that has adaptations to survive in an environment with little liquid water, such as a desert such as the Sahara or pl ...

s) and

liana A liana is a long- stemmed, woody vine that is rooted in the soil at ground level and uses trees, as well as other means of vertical support, to climb up to the canopy in search of direct sunlight. The word ''liana'' does not refer to a t ...

defence. * Self-pruning is the shedding of branches that are shaded or diseased, which are potentially a drain on the resources of the tree. * Drought response is similar to the leaf-fall response of drought-deciduous trees; however, leafy shoots are shed in place of leaves. Western red cedar (''

Thuja plicata ''Thuja plicata'' is an evergreen coniferous tree in the cypress family Cupressaceae, native to western North America. Its common name is western redcedar (western red cedar in the UK), and it is also called Pacific redcedar, giant arborvitae, w ...

'') provides an example, as do other members of the family

Cupressaceae Cupressaceae is a conifer family, the cypress family, with worldwide distribution. The family includes 27–30 genera (17 monotypic), which include the junipers and redwoods, with about 130–140 species in total. They are monoecious, subdioeci ...

. * In tropical forests, infestation of tree canopies by woody climbers or

s can be a serious problem. Cladoptosis – by giving a clean bole with no support for climbing plants – may be an adaptation against lianas, as in the case of '' Castilla''.

References

External links

Cladoptosis in ''Thuja''
- UBC Botanical Garden Plant physiology Plant anatomy

Functions of cladoptosis

See also

References

Further reading

External links