Tree pine ("Pinus" species) the bark exudes sticky resin which deters attackers whereas in rubber trees ("Hevea brasiliensis") it is a milky latex that oozes out. The quinine bark tree ("Cinchona officinalis") contains bitter substances to make the bark unpalatable. Large tree-like plants with lignified trunks in the Pteridophyta, Arecales, Cycadophyta and Poales such as the tree ferns, palms, cycads and bamboos have different structures and outer coverings. Although the bark functions as a protective barrier, it is itself attacked by boring insects such as beetles. These lay their eggs in crevices and the larvae chew their way through the cellulose
USS Cinchona (AN-12) USS Cinchona (AN-12) USS "Cinchona" (AN-12/YN-7) was an "Aloe"-class net laying ship which was assigned to serve the U.S. Navy during World War II with her protective anti-submarine nets. "Cinchona" (YN-7) was launched 2 July 1941 by Commercial Iron Works, Portland, Oregon; sponsored by Mrs. W. Casey; outfitted by Puget Sound Navy Yard; and placed in service 15 August 1941, Lieutenant H. H. Breed, USNR, in charge. Assigned to the 14th Naval District, she arrived at Pearl Harbor 17 October where she took up duty in net repair and replacement, salvage of gear lost or adrift, and maintenance of net