Resin canals or resin ducts are elongated, tube-shaped intercellular spaces surrounded by

epithelial cells Epithelium or epithelial tissue is one of the four basic types of animal tissue, along with connective tissue, muscle tissue and nervous tissue. It is a thin, continuous, protective layer of compactly packed cells with a little intercell ...

which secrete

resin In polymer chemistry and materials science, resin is a solid or highly viscous substance of plant or synthetic origin that is typically convertible into polymers. Resins are usually mixtures of organic compounds. This article focuses on n ...

into the canal. These canals are orientated longitudinally and radially in between fusiform rays. They are usually found in late wood: denser wood grown later in the season.

Resin In polymer chemistry and materials science, resin is a solid or highly viscous substance of plant or synthetic origin that is typically convertible into polymers. Resins are usually mixtures of organic compounds. This article focuses on n ...

is antiseptic and aromatic and prevents the development of fungi and deters insects.

Types

* Normal resin canals exist naturally in the wood of the genera ''Picea'', ''Larix'', ''Pinus'', ''Pseudotsuga'' and ''

Shorea Fruit of a ''Shorea'' species ''Shorea'' is a genus of about 196 species of mainly rainforest trees in the family Dipterocarpaceae. The genus is named after Sir John Shore, the governor-general of the British East India Company, 1793–1798. T ...

''. * Traumatic resin canals may be formed in wounded trees that don't have normal resin canals. Wounding occurs from either fire, freezing or mechanical damage. These canals are irregularly shaped compared to normal resin canals.

Characteristics

Resin canal characteristics (such as number, size and density) in pine species can determine its resistance to pests. In one study, biologists were able to categorize 84% of

lodgepole pine ''Pinus contorta'', with the common names lodgepole pine and shore pine, and also known as twisted pine, and contorta pine, is a common tree in western North America. It is common near the ocean shore and in dry montane forests to the subalpin ...

, and 92% of limber pines, as being either susceptible or resistant to bark beetles based only on their resin canals and growth rate over 20 years. In another study, scientists found

ponderosa pine ''Pinus ponderosa'', commonly known as the ponderosa pine, bull pine, blackjack pine, western yellow-pine, or filipinus pine is a very large pine tree species of variable habitat native to mountainous regions of western North America. It is the ...

trees that survived drought and bark beetle attacks had resin ducts that were >10% larger in diameter, >25% denser (resin canals per mm²), and composed >50% more area of per ring.Kane, J.M. & Kolb, T.E. Oecologia (2010) 164: 601. https://doi.org/10.1007/s00442-010-1683-4

Types

Characteristics

References

Further reading