Mexican Bunchgrass and Zacatonal - Code: Ne7F

Mexican Bunchgrass and Zacatonal is a rare subalpine grassland limited to the highest mountains in the Sierra Madre Occidental and the volcanic belt. Typically occurring from 8,000-13,000 ft (2,400-4000m), in rare cases alpine grasslands can exist as high as 15,500ft (4800m).  This is a cold and semi-arid environment with the upper elevations regularly reaching temperatures well below freezing. In many ways this habitat is a transitional habitat intermediate between Nearctic Alpine Tundra and the paramos of South America. 
Mexican Bunchgrass and Zacatonal varies as you travel upslope. At the low and middle elevations, this grassland exists as small park-like meadows within the upper reaches of Madrean Pine-Oak forest. Mexican Bunchgrass clearings are surrounded by savanna-like stands of Montezuma Pine (Pinus montezumae) and dominated by Toluca Fescue (Festuca tolucensis), muhly (Muhlenbergia quadridentate), and Peruvian Feathergrass (Jarava ichu) which grow in large tussock 3-5ft (1-1.75m) tall with flower spikes reaching even higher. The grasses growing here make the terrain uneven and hummocked – especially difficult to traverse for a grassland. At higher elevations 12,500 to 13,800 ft (3800-4200m) Zacatonal ascends above treeline and becomes significantly more uniform, losing the heavily tussocked bunchgrass appearance. At this elevation Toluca Reed-grass (Calamagrostis tolucensis) is the dominant species before being replaced by the short, alpine Fescue (Festuca livida) near the upper limits of vegetative growth.