The Collaborative International Dictionary of English v.0.48:

Creosote bush \Cre"o*sote bush\
   A shrub (Covillea mexicana) found in desert regions from
   Colorado to California and southward through Mexico. It has
   yellow flowers and very resinous foliage with a strong odor
   of creosote.
   [Webster 1913 Suppl.] Crepance

WordNet (r) 3.0 (2006):

creosote bush
    n 1: desert shrub of southwestern United States and New Mexico
         having persistent resinous aromatic foliage and small
         yellow flowers [syn: creosote bush, coville,
         hediondilla, Larrea tridentata]