Question: Coleophora laricella was known to be a deforester of which species of tree found in the western United States?
Context: Coleophora laricella, the western larch case-bearer, is a moth belonging to the family of case-bearing moths Coleophoridae.  It is native to Central and Northern Europe, with its original food source being the European larch or "Larix decidua".  However, it was introduced to North America in the mid-19th century where it has gained a wide range and become an invasive defoliater of several species of the genus "Larix", particularly the western larch "Larix occidentalis" and the tamarack larch "Larix laricina". The Droopy Leaf, Aglaia elaeagnoidea, commonly known as Priyangu, is a species of plant in the Meliaceae family.  It is a 10m tall tree found in American Samoa, Australia (Western Australia and Queensland), Cambodia, India, Indonesia, Malaysia, New Caledonia, Papua New Guinea, the Philippines, Samoa, Sri Lanka, Taiwan, Thailand, Vanuatu, and Vietnam. Pinus glabra, the spruce pine, is a tree found on the coastal plains of the southern United States, from southern South Carolina south to northern Florida and west to southern Louisiana.  This pine is a straight-growing, medium-sized species, attaining heights of 20–35 m. Ulmus pseudopropinqua , occasionally known in the United States as the Harbin spring elm, is a small deciduous tree found only in Heilongjiang, the northeasternmost province in China.  The tree has not been studied comprehensively, and it has been speculated it may be a natural hybrid of "Ulmus davidiana" var.  "japonica" and "Ulmus macrocarpa". Ehretia anacua is medium-sized tree found in eastern Mexico and southern Texas in the United States.  It is a member of the borage family, Boraginaceae.  One of its common names, anacua, is derived from the Mexican Spanish word "anacahuite", as is that of the related "Cordia boissieri", the "anacahuita".  That word in turn is derived from the Nahuatl words "āmatl", meaning "paper," and "quatitl", meaning "tree," possibly referring to the bark.  It is also known as knockaway, a corruption of anacua, and sandpaper tree. Erythrina herbacea, commonly known as the coral bean, Cherokee bean, Mamou plant in South Louisiana, red cardinal or cardinal spear, is a flowering shrub or small tree found throughout the southeastern United States and northeastern Mexico; it has also been reported from parts of Central America and, as an introduced species, from Pakistan.  Various other systematic names have been used for this plant in the past, including "Erythrina arborea", "Erythrina hederifolia", "Erythrina humilis", "Erythrina rubicunda", "Corallodendron herbaceum" and "Xyphanthus hederifolius". Western larch (Larix occidentalis) is a species of larch native to the mountains of western North America, in Canada in southeastern British Columbia and southwestern Alberta, and in the United States in eastern Washington, eastern Oregon, northern Idaho, and western Montana. Combretum erythrophyllum, commonly known as the river bushwillow, is a medium-sized to large, spreading tree found in bush along river banks in southern Africa.  It is planted as a shade and ornamental tree in South Africa and the United States, and is propagated by seed. The metallic coleophora moth (Coleophora mayrella) is a moth of the Coleophoridae family.  It is native to Europe and Armenia, but is an adventive species in the Nearctic ecozone, where it is found throughout the United States and southern Canada.  It has also been recorded from New Zealand, Chile and Argentina.  The habitat consists of grassy areas and waste ground. Pinus longaeva (commonly referred to as the Great Basin bristlecone pine, intermountain bristlecone pine, or western bristlecone pine) is a long-living species of bristlecone pine tree found in the higher mountains of California, Nevada, and Utah.  One member of this species, at 5067 years old, is the oldest known living non-clonal organism on Earth.  In 1987, the bristlecone pine was designated one of Nevada's state trees.
Answer: Larix occidentalis