Photo Story--Beautiful, Stark Salta, Argentina

Just as in North America, the prevailing winds bring moisture from the Pacific that drops on the mountains, making a dry zone at their base in eastern Oregon and Washington and on the Colorado Front Range, so in South America, the winds from the Pacific leave their water on the west side of the Andes and at the base of the mountains, on the east, it is very dry. This effect is the most dramatic as you approach the tropics, in North America in Arizona and northern Mexico, in South America in northwestern Argentina's Jujuy and Salta Provinces.

 

Rocky landscape of Salta Province

 

Plant Story--Colorful Common Tansy, Tanacetum vulgare

Tansy is a small plant with bright yellow flowers and a spicy smell (scientific name, Tanacetum vulgare sunflower family, Asteraceae). It is native to western Asia but long ago became an herb and spice that was grown throughout Europe and then transported by Europeans all over the world. Today we know it more as a garden flower or roadside weed than as a flavoring or medicine, but it is all of those. 

common tansy, Tanacetum vulgare

Plants and Pollinators

 One of the ideas that attracted me to ecology as a student was pollination. In particular, the match between flowers and their visitors. Bees like open flowers like echinacea and bees can enter closed flowers like peas, but some flowers are too long and narrow for them to reach the nectar. This results in patterns in nature, plants that are mainly bee-pollinated, for example, and plants that are not pollinated by bees. And those bee-flowers share characteristics, so that you can recognize them, just as bees do. 

Bumblebee drinking nectar from golden banner (Thermopsis montana)

                                The pollen and stigma are hidden inside the lower lips of the flower,

                                   they bump into the bee's abdomen as it feeds, transferring pollen.

Plant Story--Handsome Ten-Petal Blazingstar, Mentzelia decapetala

The blazingstars, genus Mentzelia, are an American group, but especially western North American. Some species are found in the Caribbean, Central, and South America but 85 of the approximately 95 species are North American. If you live in the eastern half of the United States, you can be forgiven for never having heard of this group, because only three species have ranges east of the Mississippi. (Those are a Florida endemic and two found east to Illinois). Colorado has 25 species, almost all in the western half of the state, west of the Rocky Mountains; only four species grow on the eastern plains. They are in the small plant family Loasaceae, the blazingstar family.

ten-petal blazingstar, Mentzelia decapetala, at night