Thuja occidentalis, a species of thuja, is an evergreen coniferous tree in the cypress family Cupressaceae, native to the northeastern U.S. and southeastern Canada, from central Saskatchewan east to New Brunswick, and south to eastern Tennessee in the Appalachian Mountains.

Unlike the closely related Thuja plicata (Western Redcedar), it is only a small tree, to 10-20 m tall and 0.4 m trunk diameter (exceptionally to 30 m tall and 1.6 m diameter). The bark is red-brown, furrowed and peels in narrow, longitudinal strips. The foliage forms in flat sprays with scale-like leaves 3-5 mm long. The cones are slender, yellow-green ripening brown, 10-15 mm long and 4-5 mm broad, with 6-8 overlapping scales.
It grows naturally in wet forests, being particularly abundant in swamps where other larger and faster-growing trees cannot compete successfully. It also occurs on other sites with reduced tree competition such as cliffs.
Ref:
-Conifer Specialist Group (1998). Thuja occidentalis. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 12 May 2006.
-Gymnosperm Database:
Thuja occidentalis (http://www.conifers.org/cu/th/occidentalis.htm)
by Scott Horley.

Bristlecone pine: (Pinus Balfourianae) A small group of pine trees that can reach an age far greater than that of any other single living organism known, up to nearly 5,000 years.

These pines grow in isolated groves at and just below the tree line. Because of cold temperatures, dry soils, high winds, and short growing seasons, the trees grow very slowly. The wood is very dense and resinous, and thus resistant to invasion by insects, fungi, and other potential pests. As the tree ages, much of its vascular cambium layer may die, in very old specimens often leaving only a narrow strip of living tissue to connect the roots to the handful of live branches.
Ref:

Bailey, D. K. 1970. Phytogeography and taxonomy of Pinus subsection Balfourianae. Ann. Missouri Bot. Gard. 57: 210-249.

Richardson, D. M. (ed.). 1998. Ecology and Biogeography of Pinus. Cambridge University Press, Cambridge

Scott Horley.