A Wandering Botanist: A Glimpse of Northern Argentina

North and west of Buenos Aires, Argentina becomes more and more tropical and then rises toward the Altiplano and the Andes. The rainfall drops to a few inches a year, which fall during the hot summer.

northwest Argentina

To the west, northern Chile sits on the Altiplano, over 10,000' above sea level, with the surrounding mountains even higher.

Looking across the Chilean Altiplano

I visited in October--spring in the Southern Hemisphere--on a Mountain Sobek tour led by Brian Weirum (link). We flew from Buenos Aires to Salta in Salta Province. The flight cruised the plains (pampas) of Argentina and then suddenly the land rose. I had thought of the Andes as The mountains of South America, but in fact a series of mountain ranges run north-south to the east of the Andes. The Nevado de Cachi range, on the west side of Salta Province, rises to 20,931' (6380 m) at their highest peak, Cumbre Liberator. The flight to Salta felt like approching Denver from the east: rolling plains abruptly became mountains, except that Denver is on the plains at the base of the mountains and Salta is in a valley beyond the first mountain range.

Salta is 1000' lower than Denver with a milder climate--almost no frosts or days in the 90s. It is also wetter with about 28" of rain a year, mostly in summer (December to March).

Much of Salta Province is drier than the city of Salta. Cafayate gets 17", almost all in the summer (link), Molinos only 6", again in summer (link)

The road south to Cafayate had glorious rock formations.

.
Through irrigation--mountain runoff runs through the region toward the Atlantic--the area is a major grape-growing region, producing Malbec and Torrentes wines. Argentines eat well and the local wines were delicious.

Like New Mexico and Arizona, when you look to unwatered vegetation, it is another story. The native plants were tough and spiny. Since it was October, most native plants were dormant, waiting for the summer rains.

One very visible plant was the cardón, the columnar cactus Echinopsis atacamensis. It looks similar to saguaro of the US southwest (Carnegiea gigantea) and the elephant cactus (also called cardón, Pachycereus pringlei) ) in Mexico. Here cardón was growing at over 10,000' in elevation. Even at 10,000', in northwestern Argentina, frosts are rare.

cardón

Looping north again past the city of Salta, we entered Jujuy Province, Argentina's far northwest. There we visited Purmamarca, a World Heritage site--for both landscape and culture--in Humahuaca Canyon. It was a pretty place with colored rock formations and a marketplace full of equally colorful Andean products.

Purmamarca, Argentina

The following day we drove up the mountains of the western edge of Argentina to Jama Pass (at 13,780') and across the border between Argentina and Chile. The border runs along the divide, with its highest point on the road at 15,420'. Clouds from the Atlantic supplement the rainfall on the east-facing mountains so we drove through fog and drizzle all the long steep climb up the mountainside

and emerged into sunlight just about at the top of the road. We crossed through a customs station where the two countries had adjacent booths in a single building.

Close to the Argentina-Chile Border, Argentina Route 52

Although we had climbed 5000' to that high pass out of Argentina, we didn't go down again into Chile. This was the Altiplano, a high dry plain that runs across northern Chile at an average elevation of 12, 300 feet above sea level.