Fraser fir adelgid mortality. The decline of the Fraser fir in the southern Appalachians has contributed to loss of moss habitat which supports the spruce-fir moss spider. The Fraser fir is an endangered species. Threats include climate change, balsam woolly adelgid and destruction of trees for Christmas trees and timber. Although not important as a source of timber, Fraser fir is widely used as a Christmas tree. Its mild fragrance, shape, strong limbs, and ability to retain its soft needles (which do not prick easily when hanging ornaments) for a long time when cut make it one of the best trees for
Noble metal Noble metal In chemistry, the noble metals are metals that are resistant to corrosion and oxidation in moist air (unlike most base metals). The short list of chemically noble metals (those elements upon which almost all chemists agree) comprises ruthenium (Ru), rhodium (Rh), palladium (Pd), silver (Ag), osmium (Os), iridium (Ir), platinum (Pt), and gold (Au). More inclusive lists include one or more of mercury (Hg), rhenium (Re) and copper (Cu) as noble metals. On the other hand, titanium (Ti), niobium (Nb), and tantalum (Ta) are not included as noble metals although they are very resistant to corrosion. While the