Prostrate Juniper, Juniperus communis var. depressa

The prostrate juniper is, as the name says, a juniper that runs along the ground, like a ground cover, and does not stand tall like a tree. North America has two such junipers, the prostrate juniper, Juniperus communis variety depressa and the creeping juniper, Juniperus horizontalis. Both are native, but prostrate juniper is more widespread, found over most of the continent (map). The common juniper, Juniperus communis, is the most widespread woody plant in the world, growing across Eurasia as well as North America. With a range that big, it is very variable and seven distinctive varieties are recognized. In Eurasia it is mostly an upright tree, though one variety, J. communis var. saxatilis, is prostrate. There is no close relationship between the two prostrate forms and J. communis var. depressa colonized all of North America. 

prostrate juniper, Juniperus communis var. depressa

Plant Story--Harebells and Bluebells, Campanula rotundifolia

The little blue flowers are always a delight to see. Its a harebell, Campanula rotundifolia (harebell family, Campanulaceae), seen in the Colorado Rocky Mountains. 

harebell, Campanula rotundifolia

Musing about Recycling

Recycling is on my mind because a National Public Radio (NPR) study (link) last month found that plastic recycling is basically not happening; most of the plastic goes to landfills. And always has. What? I am a believer in recycling.

Plant Story--Lupines, Little Wolves

Lupines, also spelled lupins, are plants in the pea family native (Fabaceae). More than 200 species are recognized, found native all across the world but especially the Americas. (Lupines in Texas and surrounding states are often called bluebonnets.) These are distinctive plants, the leaves tending to be compound with five or more leaflets projecting out from the center so they are hand- or star-like. The flowers are a tall spike of closed, pea-like blossoms, in colors from white to yellow to pink, blue, and purple. 

Future of the Alpine Tundra

arctic tundra in Sweden, 1980s

The tundra is the coldest ecosystem on earth, found in the Arctic and high on mountains. As the coldest, it is changing rapidly from global warming. World temperature is up by about 2o Fahrenheit over the last 100 years (link) but at the poles it is up twice that (link). The average temperatures on high mountains (Alps, Rocky Mountains) are up 3o Fahrenheit during that time. In arctic tundra, the permanently frozen ground is melting, forming lakes, in other places it is drying out and has caught fire, while glaciers and sea ice are melting, all of these imperiling cold-adapted animals and plants and the people who depend on them. At high elevations, conditions are rapidly changing as well. On mountains, animals and plants will migrate higher for cooler conditions, but when the summit gets too warm, they will die out.

Alpine Tundra Wildflowers in Rocky Mountain National Park

Life is hard for plants of the alpine tundra (previous post link). Alpine tundra is the ecosystem above treeline, in the United States from about 10,000' elevation up. The growing season is short, about three months. Frosts occur most nights all year and snow can fall any day. 

                     

The soil is unstable as the water in it freezes (expanding) and thaws (contracting). The soil shifts and the rocks steadily move around. Plant roots are displaced, making them sprawl. There is little cover, thin atmosphere, and less distance to the sun, so sunlight is very strong, despite cool temperatures, making sun damage to tissues much more common than better-protected places.

Alpine Tundra in Northern Colorado

Tundra is the ecosystem where it is too cold for trees. It can be too cold because the growing season is too short or because the soil is frozen (permafrost) much of the time and, in the brief periods when it is not frozen, shifts, knocking trees over, usually both. Tundra is found in the Arctic (in the Antarctic, ocean fills the area that would have tundra) and high on mountains. It is the coldest ecosystem on earth.

alpine tundra is above the highest trees

Ecologists try to reduce the world's ecosystems to a minimum number. Of land ecosystems, called biomes, they can be reduced to forest, grassland, desert, and tundra. For people in the lower 48 United States, tundra is hardest biome to see. There is no arctic tundra in the lower 48 and alpine tundra occurs only on the tops of mountains. There are areas of alpine tundra high in the mountains of New York and New England, a chain of spots of tundra along the Rocky Mountains above 10,500 feet, and a similar chain of tundra when you get high enough in the Sierras and Cascades. Rocky Mountain National Park has the most accessible alpine tundra, because Trail Ridge Road will let you drive right up to it. And it is pretty extensive, something like 149 square miles in all the park (though some of it is way too steep for people or on an isolated peak). I wanted to see all the biomes of the world. Tundra was the last of the four I reached.