Root Succulence


Apical Meristems







Published papers



Field research on

cacti in South America



 See A Cactus Odyssey for more information about field research travels in South America.

    This page of the website is intended to describe the glamour and ease of field research. Most of my research is done in a modern, air-conditioned lab, of course, just a few feet from the Drag (the business street next to the UT campus, with restaurants, taverns, Texadelphia and The Hole in The Wall) but for some reason I have preferred to study specimens that have grown under natural conditions in their own hot, dry, dusty habitats far from both barbecue and Shiner Beer. That means fairly extensive travel through much of Central and South America, the home to the great majority of cacti (cacti originated and diversified greatly in South America for millions of years before finally spreading north to Mexico and the United States). Although many cacti are indeed desert plants, a large percentage of them are adapted to grasslands, forests, rainforests, and even high altitude alpine areas, so field work on cacti might mean travel through rain, mud, and near-freezing conditions – and it is not easy to buy rain gear or heavy winter coats in Texas.

Vehicles and roads.

    The first thing that is necessary for tracking down cacti is a good field vehicle. In much of South America, the major cities are connected by good, paved roads that allow you to zip along at 60 or 70 mph. But of course few cacti grow in such convenient locations and it is a good idea to have a four-wheel drive vehicle that can survive on dirt roads, navigate up dry washes that serve as roads when it is not raining, or that can follow along a semi-scraped trail that a bulldozer might have "cleared" at some point in the long-distant past. So much for good ideas – I often participate in special courses on desert plant biology at local universities and they then provide a bus and some neophyte students for a field trip. A university bus and a 4W drive jeep are at opposite ends of the spectrum of field vehicles, but buses have gotten us into – and out of – many precarious places in South America. Having a bulldozer nearby doesn’t hurt.

The Universidad Nacional Agraria La Molina in Lima, Peru, has provided this bus for our field work many times.

 It is always handy to have a bulldozer nearby, especially if it has been raining.

    Dirt roads are not too bad. In the dry season – which for most deserts is most of the year – they are smooth and flat and hard, and you and zoom along at 40 or 50 mph, depending on how much bouncing and jostling your spine can tolerate. But of course few plants grow where there is never, ever any rain, so if the almanac says that the rainy season is over at the beginning of April, don’t plan your trip for the last of March. Many remote areas just don’t have bridges, none at all: a road will simply cut down to the river bed and emerge from the other side, which is just fine when the river is bone dry.

    Mountain roads are special. Most of the Andes – home to scores of cactus species – are higher than the Rocky Mountains of the USA, but whereas Interstate 70 has four well-paved lanes sweeping easily through the Rockies, most roads crossing the Andes tend to be a bit narrower and to have tighter curves that are not quite as safe at 70 mph. Even under dry conditions they can be scary, but when it is raining, you face the possibility that the road will wash away ahead of you, and by the time you have turned around, it has washed away behind you. I must admit, I have never been stuck on a mountain road longer than four or five hours, and was able to use that time to look for cacti.

    Not a bad road, at least during daylight.     Best not to look down.     Only 4 inches of mud between the outermost tire and the edge of the cliff.
   Nice flat dirt road in Bolivia -- easy traveling.    Nice flat dirt road in Bolivia, 30 minutes later -- stuck for hours waiting for it to dry out.     One road, one railroad, one bridge -- perfectly safe as long as no train is coming and if you don't stop in the middle to take pictures.

Helpful signs.

    Of course, if you are going to be traveling in Latin America, it helps to speak Portuguese (if in Brazil) or Spanish (everywhere else); Latin won’t quite work anywhere. You may have heard that you can get along even if you don’t speak the local language because there will always be someone around who speaks English; that is true enough in all large cities. But, yes, you guessed it, cacti don’t grow in large cities. And out in the countryside, most cacti are probably as fluent in English as most of the local folks. But never fear, often there will be informational signs that you can figure out even if you know just a bit of Spanish.

    Ummmm, no cactus here.      Didn't help as much as we'd hoped.     UT folks are so popular everywhere that people put out signs welcoming us Longhorns. Photo by James Folsom.
    This verb is pretty rare.    Se prohibe......     We just kept driving to the nearest bar.


    Variable. Outside the big cities, hotels are never expensive. They will probably be much, much simpler than anything most Americans ever experience, but after a long day photographing, collecting and dissecting plants, the only thing you will be interested in is a clean room, a shower, dinner and a means of rehydrating (just in case anyone reading this needs convincing: beer is always sterile [if you drink it directly from the bottle], has water that will rehydrate you, carbohydrates for energy, and electrolytes).

    Field accommodations for molecular geneticists, not plant anatomists.     This abandoned sawmill in Panama was home while searching for epiphytic, rainforest cacti.     Sleeping accommodations in the abandoned sawmill: a sleeping bag in string hammock. The hammock opens out to be a real hammock only if you get into it carefully enough to not fall on your butt in the process.
     An airy place to sleep in Bolivia, but it is best to never sleep under thatched roofs -- they are breeding grounds for the beetles that carry Chagas disease.     Choco village in southern Panama was home for a few days.      Choco kids.


    Food is excellent everywhere in Latin America. Breakfast is usually bread/pastry and rich coffee (especially the café con leche). It is worth the time and trouble to go to Argentina just for the coffee and medias lunas. Lunches can be bread and cheese out in the field or some sort of sandwich and papas fritas in a restaurant. Dinner varies by the country: Argentina has beef (duh), and in Chile you would swear you are eating a great home-cooked meal in the American Midwest; Bolivia has stews that are wonderful. Peru seems to have the most varied food, but a newbie at field research in Peru should not pass up cui (roast guinea pig, served with head, tail and all four legs intact -- I have not met a gringo yet that has ordered it a second time). On the other hand, I have had the best pizza ever in Churín, Peru. For a really out of the ordinary experience, try dining in a local marketplace. All but the smallest towns have a marketplace that sells all sorts of vegetables, meat (usually in a form so complete that you can identify it to species) and eggs as well as general produce such as clothing, pots and pans, and CDs. Most markets have short-order food stalls where you can watch your food being prepared. Another dining experience that will confirm you are not in Kansas anymore is to try a parrillada: the restaurant brings you a brazier with hot coals and various cuts of meat which finish cooking at your table. Don’t be a coward and order solamente musculos (muscle meat like we eat in the US),  instead get a gran surtido: you will have the opportunity to eat all sorts of organs that you would not have considered edible (come to think of it, most really aren’t: udder – ubre – is like eating sponge, but with less flavor).

    Biologists can encounter many plants that are unfamiliar to them in marketplaces. Corn comes in a zillion colors, sizes, shapes and uses.     Potatoes, as the Incas cultivate them.    Brooms.
    Woman selling meat in marketplace -- that is the spine of something hanging from the hook.     Ever feel like you have learned all the biology your brain can hold? Buy some more in the market.  
    Shortly before we enjoy a fresh chicken dinner.     Husks (paleas and lemmas) are removed from rice by pounding then the mix is tossed into the air on a windy day -- light husks blow away, heavier grains fall straight down.     Something our guides shot in Panama. Don't know what it was, but was pretty good cooked with rice and lots of seasoning.


    Field work in Latin America is pretty much free of any danger from large animals other than taxi drivers in big cities. An angry llama will spit at you but that is not quite the same threat as an angry grizzly in the Rocky Mountains. You also don’t have to be worried about being charged by moose, buffalo, bears or mountain lions, although there are large cats in Bolivia and Brazil. Poisonous snakes do occur in the desert regions but often areas rich in cacti have so much open ground and such sparse vegetation that snakes are visible from a distance. Studying rainforest cacti will bring you into contact – or at least hearing range – of many interesting animals. I’m not sure which makes more racket – troops of howler monkeys or flocks of parrots – but hearing howler monkeys as you are setting up camp in a rainforest will definitely encourage you to pitch your tents as close together as possible. For those of you who do not like snakes, keep in mind that rainforests provide a three-dimensional habitat for snakes: they can be on the ground with you, in the bushes around you and in the trees above you – ugh. Little animals will probably be your biggest worry. Any area with dry grasses and shrubs will have ticks or other little bitey things whose sole role in life is to annoy botanists.

     After searching for cacti in dense brush all morning, we stopped at a ranch house and discovered this. They were having trouble with their cattle because there were so many jaguars in the area. Afternoon was spent in the car looking out the windows.     Don't know what bugs were biting me, but only got the one leg, and the marks went away after a few weeks.     Dangerous wild animals everywhere -- but we botanists are fearless.
    Getting samples from tall cacti is not always easy (and those spines really hurt), but at least nothing can go wrong....     Well, almost nothing can go wrong....Where do you get a sterile dressing in the middle of nowhere -- cut open a fresh potato with a clean knife -- the inside is sterile and moist.     No broken bones this time.

Side benefits of field research.

    In addition to becoming familiar with plants as they occur in their own natural conditions, field research has many side benefits. First, you get to be some place cooler and less humid than Austin in the summer. Beyond that, you get to see awesome mountains, plains, forests, rivers. Only the most myopic person could travel through South America and not notice the many stunning plants other than cacti – forests of Araucaria trees, little succulent violets that look like miniature purple traffic cones, mound-like llareta plants. Ruins of ancient civilizations are everywhere, reminding you that many of the higher areas have been farmed so intensively for thousands of years that you must be careful in deciding which vegetation is natural and which has been affected by human activities. There are all sorts of interesting people to meet and work with, although often the most eccentric of characters are the other botanists you will be traveling with. Plus all the food, lodging and travel experiences – if survived – are wonderful benefits as well. So if your parents are planning on giving you a trip to London or Paris or Rome as a graduation present, tell them no, you’d rather do cactus research in South America.

     One unusual thing you might see traveling in South America: We came across a red hillside....    Farmers were gathering the red material....      Chili peppers drying in the sun. After harvest, the farmers spread the chilis on the soil for several days to dry. Although not visible in the photo, there were millions of bees everywhere on the chilis.
    Churches are everywhere...    
     Hillside covered with thousands of small terraces for cultivating crops. These were built by Incas, but Inca populations now are so low that only a few terraces are still cultivated.     Family in Cuzco, Peru -- these are not actors.    This railroad bridge in Chile was not built by Incas, of course, but by Alexandre Gustave Eiffel -- I believe he also built a tower in Paris.
    Some wonderful plants: Oreocereus celsianus growing near the border between Argentina and Bolivia.    Can you guess what this is? It is a very short "tree" of Maihuenia poeppigii, a cactus that grows at high, cold altitudes in the far southern parts of Argentina and Chile. The yellow bodies are fruits.     Oreocereus celsianus with fruits.


    This travel has  taught me many things, one is especially memorable:

   Often, our endeavors (such as studying Biology) may seem like such a long, endless road to nowhere.........     that we are tempted to cry out "Lord, give me a some kind of a sign" ....  

[End of Field Research page]