|Abies lasiocarpa or Rocky Mountain Fir, is a very large evergreen, reaching 100 to 160 feet tall, with a typical spire form. The needles are pale blue-green above, silvery gray below. The bark is a pretty gray or chalk-white. The 2- to 4-inch cones are dark purple and cylindrical. Native from Alaska to Oregon, Utah and northern New Mexico. This fir grows best in an acidic soil and cooler climates. 'Mulligan's Dwarf' has a pyramid-like habit. It has dense foliage on tiered, horizontal branches.