Abies religiosa, commonly known as the Oyamel Fir or Sacred Fir, is an evergreen coniferous tree native to the high-altitude cloud forests of central and southern Mexico and western Guatemala. It thrives at elevations between 6,900 to 13,500 feet, where it experiences cool, humid summers and dry winters. The Oyamel Fir can reach heights of 82 to 164 feet with a conical to cylindrical form, making it a medium-sized to large tree. Its needle-like leaves are dark green with distinctive blue-white bands of stomata on the undersides, which are particularly noticeable. The tree is also known for its cylindrical cones that mature to a purplish-brown color.

The Oyamel Fir is revered for its ecological role, especially as the primary habitat for the overwintering monarch butterflies in the Trans-Mexican Volcanic Belt. Its dense foliage provides the microclimate necessary for the butterflies’ survival. In cultivation, it is valued for its attractive foliage and conical shape, making it a choice for large gardens and parks in areas with suitable climates. The tree prefers cool, moist conditions and well-drained, acidic soils. It requires protection from strong winds and is best suited to full sun or partial shade. While not commonly used for timber due to its soft wood, it is occasionally harvested for Christmas trees in its native range. The Oyamel Fir is susceptible to fir broom rust and can be affected by habitat destruction and climate change, which also threaten the monarch butterfly populations.CC BY-SA 4.0