So, waking up in Caraz we were greeted with the amazing sight of the Cordillera Blanca – the White Range – so named for its high, snowy peaks. The highest one is Huascarán, the fourth tallest mountain in South America after Aconcagua in Argentina (you can see pictures of that on the Patagonia blog from a couple of months ago!), and a couple of other more southerly peaks.
The Cordillera Blanca is granite and not volcanic like the rest of the Andes, although it does suffer earthquakes, one of which caused a landslide that completely buried the town of Yungay in the 1970s.
Nevado Huascarán - at 6,768 metres tall the peak to the left is one of the highest in the Western Hemisphere
The high peaks and surrounding forests are a national park, preserving their unique flora and fauna, and of course the spectacular landscapes. There are some solanums there I would dearly love to see, but since we have not got a permit to collect in national parks this time – we decided to go to the other side of the wide valley called the Callejón de Huaylas and collect in the Cordillera Negra (Black Range – so called because there are no snow-capped peaks in it!).
Our journey began with an exciting river crossing – the main bridge was out over the Río Santa, so all traffic was directed (by way of a few oil barrels painted orange and a small sign saying 'PELIGRO' [danger]) to an old bridge where we thought the traffic was behaving in a peculiar fashion.
It turned out that the bridge was in danger of collapse toward one of the ends, so the etiquette was that all the passengers in the bus or taxi or car got out, walked across the dodgy bit of the bridge, then waited for their vehicle to come across to a secure part in the middle. Everyone then piled into the vehicles again and set off. One vehicle at a time, passengers first. Very organised.
This is the only bridge to cross the Río Santa and gives access to many communities in the foothills of the Cordillera Negra – people were being very careful indeed with it!
In the rich, fertile valley bottom there was extensive agriculture – the usual barley, wheat, peas, but with a new twist – kiwicha. This is the native grain Amaranthus caudatus, a health food craze for Europeans and Americans, but a traditional staple for Andean peoples. I haven’t seen much of it cultivated in Peru in my last few trips, but here it was quite common.
Kiwicha is high in protein and in Peru is often 'popped' and made into sugary bars a bit like flapjacks, only lighter
As usual, the road was steep and twisty – we ascended from about 2000 to nearly 4000 metres in only about 20 kilometres. The road is two-way, but really only one car-width wide, in places not even that – the uphill traffic always has priority, but if you blink, you lose your rights. Fortunately for us, even though Maria is an amazing mountain driver, there wasn’t much traffic.
The road up and over the Cordillera Negra snakes around incredible switchbacks, always with the Cordillera Blanca clearly in the distance
As we got near to the top of the pass one of Peru’s iconic plants began to appear. Puya raimondii is celebrated all over the country wherever it occurs. This member of the pineapple family is a true giant – the spiky puffball-looking plants are taller than a person, and the inflorescence (branches) on which the blue-green flowers are borne can be a much as 10 metres tall!
The plant blooms once and then dies – botanists call this monocarpic. Apparently the life span of an individual plant is around 30 to 40 years and they bloom erratically, so it is hard to catch them in flower. The ones we saw here had bloomed and were now dead – one even had a woodpecker nest hole in the inflorescence stalk.
Every single plant in this Puya raimondii population was counted for a population study done by Peruvian botanists a few years ago
In the high elevation puna we found a Nicotiana (tobacco) species we had not yet seen – Nicotiana undulata. It is a really sticky, smelly plant – covered with glandular hairs. It is one of the parents of Nicotiana rustica, one of the allotetraploid cultivated tobaccos.
Allotetraploids are formed by the fusion of two genomes to create a new entity. Nicotiana is rife with allotetraploidy, something I have been working on with Andrew Leitch of Queen Mary and Mark Chase of Kew for many years. Many of our cultivated plants are tetraploids – they are usually self-fertilizing and vigorous.
Nicotiana undulata has dirty cream-colored flowers, but up close they are quite beautiful
We stopped in a village to try to buy water (we had forgotten to do so further down….) and a lovely man proudly showed us his recently harvested potato crop. He had a good year and grew a variety he had obtained from the Callejón de Huaylas called 'yungaysina' – presumably after the town of Yungay. We asked about wild potatoes and he said no, there weren’t any in the hills any more, they were all eaten by animals like goats and cattle.
Most of this farmer’s crop was already stored in the back ready for sale – these were just the last bits of the crop
He was wrong about wild potatoes though – Paul found one up amongst the rocks! Potatoes are not my best group, but this one I ought to be able to identify once back in the herbarium
We eventually – many Solanaceae collections later – made it to the village of Pamparomas, where we found another tobacco (the other parent of Nicotiana rustica called Nicotiana paniculata) and could see far down the dry valleys and hills to the coast almost 100 kilometres away. I could feel the wild tomatoes calling from those valleys – but by this time it was 4pm and time to return to Caraz. So we snaked back up and over, and as we descended into the Callejón de Huaylas again were treated to the sunset over the Cordillera Blanca. What a last day of Solanaceae collecting in Peru for me!
Although this has been a short trip for me – longer for Tiina and Maria – we have collected more than 100 new locality records for Solanaceae in northern Peru, filling some of the gaps in the collections from the country. We found exciting plants I have never seen before in the field, and had lots of theories about why things grew where they did.
Seeing plants in the wild, in their native haunts is so important to achieving a deeper understanding of their evolution; they do quite unexpected things sometimes. I am looking forward to reports from Tiina and Maria from their next journey with Museum entomologists!