Stefan Burger is a Cacti Chaser

Stefan Burger is an Australian cacti obsessive living in Chile. Scroll through his Instagram feed and you’ll soon be feeling a weird combination of amazement, surprise, and wanderlust inspired by the mind-blowing plants he meets and the places he goes. He’s the real deal – passionate about knowing, understanding and sharing information about this most incredible plant genus. With around one third of all cactus species facing extinction, we desperately need people like Stefan – committed to sharing their experience and knowledge to promote the protection and preservation of plants. I caught up with Stefan recently to find out more about his life with plants, and his experiences of the threats to cacti species in South America, Chile in particular.

Can you please tell us a little about your early life with plants? Where did you grow up, what were your first plant experiences? How did you get to doing what you’re doing now? I grew up in a small town in Victoria, Australia, and spent a lot of time with my grandparents who were avid gardeners. My grandmother, especially. She had an incredible landscape and vegetable garden. I was always outside helping to maintain the garden as well as explore it. It was an oasis to me. I also loved being outside in general and riding my bike around town looking at people’s gardens – urban botanizing!

My specific interest in cacti was sparked by a small cactus garden my grandfather had. He became unable to care for it and my grandmother suggested I transfer the garden to my house, so I made a rock garden outside. Then I bought more cacti, and people gave me cuttings and plants. My interest just grew from there.

My family always noticed my interest in cacti. I remember my uncle bought me my first cactus encyclopedia and then my mum joined me up to the Ballarat Cactus and Succulent Society in Victoria. The members of the club really supported my interest. One of the clubs most active members, Rudolf Schultz, is a great botanist and author who also had a large cactus collection and nursery at his home. I remember going on a fieldtrip there and hearing about his cacti and succulent adventures overseas, having thoroughly explored parts of South America and South Africa. I was inspired.

Some years later I began travelling to see plants in habitat, beginning in the United States, then Madagascar, Chile, Argentina, Bolivia and Peru. I completely fell in love with the cacti of Chile. Two cactus societies in Australia have invited me to write some articles for them about my travels and observations. I have written a lot, but I find that I am always learning more about habitat, taking more observative notes, photos and further adding to my writings.

I officially moved to Chile in September 2019, after spending around 18 months travelling in South America.

Stefan Burger in 2003
Stefan Burger in 2019

Can you tell me about one the weirdest cacti you’ve ever met? This would have to be Melocactus peruvianus. Just a glance at the photo will tell you why! This otherworldly plant looks like it’s wearing a red cap that is technically known as a cephalium, derived from the Greek ‘cephalous’ meaning to have a head or heads. Basically, for around the first decade of a Melocactus’ life it looks just like any standard ball or barrel cactus, until it reaches maturity. At this point, its standard growth phase stops, and it starts to form a new type of stem from its apices – the cephalium. The Melocactus only continues to grow the cephalium from now on and cannot add to the new photosynthetic foundational tissue.

So, what is a cephalium exactly? Basically, it’s a whole bunch of areoles (the part where the spines and flowers come form) packed tightly together. Why do this? Each areole is only able to produce one flower in its lifetime, so Melocacti decided to produce less stem and many more areoles so they can produce more flowers and fruits, therefore yielding a higher reproduction rate. Pretty amazing and intelligent also! Weird cactus with mad adaptations rolled into one, right?!

Are you interested in other genus too, or is cacti your primary focus? Historically, almost anything in the order Caryophyllales has interested me. But whenever I go on a trip to find a cactus, I’m constantly finding myself noticing other plants and saying, ‘wow, that’s beautiful, I wonder what you are!’ The wonderful thing about the world of botany is that there is always something new to learn and discover. And when you become interested in the ‘why’ of plants, e.g. their evolution, adaptations, ecology, you are constantly engaged and curious. It’s a great state of mind to be in. You can begin to see and understand the interconnectedness of everything and realise how fascinating the natural world is.

Listening to you on the In Defence of Plants podcast – it seems you’re fascinated by plant adaptations – I am too! Can you describe some of the maddest cacti adaptations you know of? The world of cacti is full of fascinating and intelligent adaptations and I find them all interesting. One group that does stand out though is the Thelocephala, a subgenus of Eriosyce.

Melocactus peruvianus. Image by Stefan Burger

These are a fascinating group of plants endemic to Chile and are geophytes which spend most of their life below the ground. Around 80% of the plant or more is composed of a large underground taproot organ which stores nutrients and water. The head of the cactus is more or less just a flat pancake that really only serves for photosynthesis and reproduction, having very little water storage capacity. These cacti can lay dormant for years, even a decade, through long droughts, then when the rains arrive the head of the plant hydrates and swells up only just above ground level, helping to boost photosynthesis and send out some flowers and hopefully produce fruit too. This process uses a lot of energy and water which makes them shrink back down afterwards, allowing the wind to cover them with sand to prevent rapid dehydration as they wait for the next rain. Pretty amazing right?!

Eriosyce odieri (Thelocephala) . Image by Stefan Burger

Cacti are cool these days. They grace the front windows of hip clothing stores and live short, painful lives as houseplants, their glory days captured and shared on Instagram. I’ve read a few stories about how the craze for cacti is driving certain species to extinction, particularly in the USA. Have you seen this in South America too? This is a huge topic right now in the cacti community and is a highly emotive topic for habitat lovers. Unfortunately, yes, plants are definitely being taken from habitat in South America, particularly in Chile, Argentina and Brazil where some of the most desirable and slow growing cacti originate. The urge for someone to coordinate an international cacti heist probably stems from the length of time it takes for many of these cacti to reach maturity. Many species take decades to produce their first flower and even centuries to become an attractive specimen plant. Stealing mature plants from habitat is the easy way out, however doing this takes a huge toll on a populations by reducing the overall number of mature specimens, therefore reducing the number of flowers and seeds produced each season. This, in turn, inhibits the regeneration of future plants in an already challenging environment.

Habitat plants need to be treated with much more respect, and seen for the incredible noble and ancient wonders of evolution and adaptation that they are, where they are.

In fact, a vast majority of plants taken from habitat die soon after, as they go into shock and don’t transplant well, especially if taken into environments they’re not adapted to. It often ends up being a lose-lose situation.

There are specialist nurseries that sell plants which have been ethically grown from seed. Growers and collectors should know that seeds which have been germinated in their specific climate zones have a much higher chance of survival, in addition to ongoing and appropriate care.     

Around one third of all cacti species are endangered. What has been your on-the-ground experience of threats to cacti in South America? This is a complex topic. Internationally, cacti are being threatened by mining operations, expansion of civilization, agricultural practices and trafficking, as discussed above. Another threat that slips under the radar is extreme sport and recreation activities such as off-road 4×4 driving and motorbike and quadbike riding.

For example, there is a subgroup of Eriosyce, the Thelocephala, which are a fascinating group of plants endemic to Chile and are geophytes, meaning they live below the ground. Their habitat looks as if nothing grows there. Road construction and expansion of civilization is one thing that threatens their habitats, but another is people speeding across habitat in their 4×4’s and motorbikes which tears the ground and cacti to shreds. Other geophytes like bulbs as well as insects and animals that live in these habitats are also affected by these same threats.

There was a big problem with this type of recreational activity in Pan de Azucar National Park in Chile and certain sectors have now been barricaded, as the place was getting torn up. Extreme sport tracks were also made in highly vegetated areas of the park resulting in hundred-year-old plants being smashed up. Seedlings and other juvenile plants were crushed. There are designated areas away from vulnerable habitat zones where these types of activities can be performed without destroying habitat, so people really need to stick to using those places.

Copiapoa cinerea subspecies columna alba, Chile. Image by Stefan Burger

The changing climate is also affecting desert habitats. Deserts are already a fragile place for life to exist, even for dry climate specialists like cacti, and are impacted by a warming world. The desert can actually be a very lush place when a phenomenon called ‘desierto florido’ or flowering desert occurs after winter and springtime rains, activating a plethora of native annuals, perennials and geophytes which animals and insects rely on for survival. With extreme and prolonged droughts which we are seeing now, there is less vegetation around for animals to eat, so many herbivores such as Guanaco are resorting to eating cacti. Yes, cacti! Many of the smaller Eriosyce from the Thelocephala subgroup and Copiapoa hypogea and C. esmeraldana, for example, are weakly spined –an animal desperate to survive will resort to eating these species, which can have a devastating effect on a population. These types of cacti also have delicious taproots to store nutrients and water which animals love eating when conditions are tough.

Other animal species that have been introduced to Chile such as donkeys and goats also have a devastating effect on habitat. They eat heavily spined cacti in times of drought, such as Eulychnia and Echinopsis. They also make numerous game trails through habitat and are frequently snapping smaller cacti off at their necks. Copiapoa humilis populations have been heavily affected by wild donkeys wandering through their habitat. The guanaco and vicuna that are native to Chile have a much more organised gait pattern, not to mention smaller hooves, and don’t tend to affect cacti like donkeys do. 

What do you think are the best ways to help protect cacti and the ecosystems in which they live? Education, education and more education, indefinitely. Something that would instantly help cacti habitats is stopping people from trafficking them in the first place and governments better protecting plants that grow inside national parks. Not to say that cacti growing outside of park boundaries are free game, that comes down to education, common sense and respect for these plants. I do believe that there should be more national parks, or expansion of existing ones. This would better protect a greater number of species. There are still many diverse habitats which remain unprotected.

One thing that makes me sick to the stomach is seeing mining operations within national park boundaries. Also, funding for maintaining parks and employing park rangers has also been cut. This has happened across the board with national parks in the north of Chile, limiting the amount of area being properly surveyed, which has been correlated with an increase in plant theft from habitat and even robberies within national park boundaries.

Euphorbia lactiflua, Chile. Image by Stefan Burger

Can you please tell us about your business, Cactus Explorer? Where do you go, and who goes on your tours? Are they full of mad plant hunters? The idea of Cactus Explorer started from a whole bunch of habitat photos from my travels. At that point I didn’t have any social media and I was sharing my travel stories and pics with some fellow travellers. They were not necessarily plant fanatics but loved the photos and said I should start an Instagram page with just those habitat pictures. At the time I didn’t think that many people would be very interested, but I was quickly surprised at the response I received. Soon I had people asking if I lead habitat tours. The idea really just grew from there.

Eriosyce occulta, Chile. Image by Stefan Burger

The tours I lead visit unique cacti habitat locations as well as some of Chile’s major tourist attractions north of Santiago. Cacti tend to grow in places with spectacular landscapes. The Chilean Altiplano and Atacama Desert coastline, which are featured on my tours, are a landscape and nature photographer’s paradise. There is one Chilean genus in particular that fascinates many cacti and plant enthusiasts – Copiapoa. This is an endemic Chilean genus that grows almost exclusively along the coastline where the most precipitation occurs. The thick fog and stratocumulus cloud banks, locally known as ‘camanchaca’, settle along the coastal mountains and form wonderful fog oasis or ‘lomas’. These places are home to cacti and other xerophytes from the Euphorbiaceae, Bromeliaceae and Amaryllidaceae family, to name a few. Everyone who visits these places is fascinated by the ecology!  

Azorella compacta, Chile. Image by Stefan Burger

The Chilean Altiplano tour focuses more on the Andes, boasting forests of huge Echinopsis atacamensis that can reach up to eight metres tall, as well as three members of the genus Oreocereus, otherwise known as “Old Men of the Andes” which form long, dense stem trichomes that look like white hair. Oh, and I can’t forget to mention one of the oldest living plants in the world that grows here too – Yaretta, Azorella compacta – AKA giant green blobs! This species is in the Apiaceae family and grows incredibly slowly, and many plants can live to be over 3000 years old! The Altiplano is a remarkable place to visit. We also visit geyser fields and Lagoona Roja – the Red Lagoon!

And yes, these tours tend to attract the plant obsessed! We have a great time sharing our passion together by visiting habitat and having in depth discussions about the plants and their ecology. 

What is it about cacti that draws you in? I have always been impressed with the seemingly endless forms of cacti, the age that they can live to, as well as their xerophytic adaptations. My trips to habitat have only fuelled my interest and desire to explore, discover and learn more –there is so much natural variation between plants, even within the same species. You just don’t get to see that type of variation in cultivation, which mostly have just one phenotype of a species.

In habitat you can also see cacti and other plants that could easily be 500 to 1000+ years old, more than five to ten times my life expectancy. There is just so much wonder out there!

If you were a cactus, which species would you be? I would be Copiapoa hypogaea. I think it has one of the best seats in the house.

Copiapoa hypogaea var. barquitensis, Chile. Image by Stefan Burger
Eriosyce rodentiophila, Chile. Image by Stefan Burger