Monkey Puzzle Tree Araucaria araucana

The Araucaria genus is comprised of approximately 19 species of pine-like conifers indigenous to the Southern hemisphere. A. araucana or Monkey Puzzle Tree is the hardiest of these species. It is a large, stately evergreen conifer native to the volcanic hills of the Andes mountains in southern Chile and western Argentina. It is the national tree of Chile and thrives in maritime areas with mild, cool, climates. It is sometimes called a living fossil due to its longevity and unusual appearance resembling fossilized plants.

Juveniles are conical or pyramidal with sparse, symmetrical, rope-like branches forming an open growth habit. At maturity, the crown broadens into an umbrella-shaped canopy atop a tall straight trunk with few lower branches. Native specimens can live to 1000 or more years. In the 18th century, Spanish colonizers took specimens, introducing it then to England and subsequent nursery commerce. In its native setting, it reaches a height of 130 feet with a 7-foot diameter trunk. Cultivated specimens are typically much smaller (60-70 feet tall x 30-35 feet wide).

This tree is not naturalized in North America, and cold hardiness only to USDA zone 7 limits its use in the U.S. However, it has potential as a unique garden specimen in some areas of the south, southwest and west coast U.S. This tree has few pests or diseases and thrives best with full sun, well-drained soil and frequent watering. It tolerates nearly any type of soil, including clay, provided it is well-drained. It grows best in open, full sun locations with ample room to accommodate its large size when mature. Additional site considerations are surface roots that may interfere with lawn mowing and lift sidewalks or hardscaping. Fallen cones may be an undesirable litter or pedestrian nuisance.

Insects, Diseases and Other Plant Problems:  This tree does not tolerate urban pollution.  It is generally pest resistant but has some susceptibility to scales, leaf spot, phytophthora, root rot and sooty molds.  Siting must allow adequate space for this tree's large size at maturity as surface roots are capable of lifting sidewalks and impeding lawn mowing.  Large falling cones may be an undesirable litter or pedestrian issue.

VIDEO created by Ryan Contreras for “Landscape Plant Materials I:  Deciduous Hardwoods and Conifers or Landscape Plant Materials II:  Spring Flowering Trees and Shrubs” a plant identification course offered by the Department of Horticulture at Oregon State University