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Crown shyness (also canopy disengagement, canopy shyness, or intercrown spacing) is a phenomenon observed in some tree species, in which the crowns of fully stocked trees do not touch each other, forming a canopy with channel-like gaps. The phenomenon is most prevalent among trees of the same species, but also occurs between trees of different species. There exist many hypotheses as to why crown shyness is an adaptive behavior, and research suggests that it might inhibit spread of leaf-eating insect larvae.

Smokejumpers are specially trained wildland firefighters who provide an initial attack response on remote wildland fires. They are inserted at the site of the fire by parachute.

Smokejumpers are trained and experienced wildland firefighters. In addition to performing the initial attack on wildfires, they may also provide leadership for extended attacks on wildland fires. Shortly after smokejumpers touch ground, they are supplied by parachute with food, water, and firefighting tools, making them self-sufficient for 48 hours. Smokejumpers are usually on duty from early spring through late fall.

Shellac () is a resin secreted by the female lac bug on trees in the forests of India and Thailand. Chemically, it is mainly composed of aleuritic acid, jalaric acid, shellolic acid, and other natural waxes. It is processed and sold as dry flakes and dissolved in alcohol to make liquid shellac, which is used as a brush-on colorant, food glaze and wood finish. Shellac functions as a tough natural primer, sanding sealant, tannin-blocker, odour-blocker, stain, and high-gloss varnish. Shellac was once used in electrical applications as it possesses good insulation qualities and seals out moisture. Phonograph and 78 rpm gramophone records were made of shellac until they were replaced by vinyl long-playing records from 1948 onwards.

From the time shellac replaced oil and wax finishes in the 19th century, it was one of the dominant wood finishes in the western world until it was largely replaced by nitrocellulose lacquer in the 1920s and 1930s.