An Oasis in the Heights
Flora and Vegetation of the Pehuenche Pass.
Flora
Maule Lake
Biodiversity
by Joao de la Cruz
Joao is a flora specialist originally from Molina, Maule Region. He has worked on numerous flora studies throughout Chile, including a flora inventory of the Maule mountain range carried out by the Pillanmapu Geopark Foundation in 2023.
December 11, 2025
The Andes Mountains in the Maule Region, specifically in the area encompassing the Laguna del Maule volcanic complex and the Paso Pehuenche international route, constitute a natural laboratory of incalculable biological value. Upon ascending above 2,000 meters above sea level, the visitor leaves behind the sclerophyllous and deciduous forest of the central valley to enter an ecosystem dominated by volcanic sands, wind, and vegetation that has perfected the art of survival: the High Andean steppe.
Typical landscape of the Maule high Andean steppe. Joao de la Cruz.
Adaptation to the Limit
The area surrounding Laguna del Maule is characterized by extreme climatic conditions. Winters are blanketed in meters of snow, summers are characterized by high levels of ultraviolet solar radiation, strong winds, and volcanic soils (pumice and rhyolite) with low moisture retention. In response to these stressful factors, the flora has developed remarkable morphological and physiological adaptations.
The predominant vegetation is low-growing, rarely exceeding 50 centimeters in height. This plant structure serves a dual purpose: preventing mechanical damage from the wind and harnessing the heat radiated by the ground during the day.
Survival Strategies:
- Bearing habit: Plants that grow compact and close to the ground to conserve temperature and humidity inside.
- Pubescence: Many leaves are covered with fine whitish "hairs" or toments, which reflect excessive solar radiation and reduce water loss.
- Deep root systems: Extensive roots capable of anchoring the plant in unstable substrates and seeking water in the deep layers of volcanic soil.
Calceolaria arachnoidea ssp. arachnoidea with its whitish "hairs" that reduce radiation. Joao de la Cruz.
Azorella prolifera. One of the eight species that make up the "llareta" group, with its cushion-like habit. Joao de la Cruz.
Floristic Composition: The Protagonists of the Steppe
The flora in this area is mostly classified within the Upper Andean Zone. The most relevant groups and species that visitors can observe are detailed below.
1. Grasses and “Coirón”
The visually dominant element on the slopes is the Coirón. It is not a single species, but a group of grasses from the genera Festuca, Pappostipa and Stipa. These plants form tufts (which form lawns), with hard and sharp leaves.
- Ecological value: They are the engineers of the ecosystem. Their roots anchor the soil, preventing wind and water erosion, and act as nurse plants, allowing other more delicate species to germinate under their shade and protection.
Landscape dominated by coirones grass. In the background, the Campanario volcano. Joao de la Cruz.
2. Low and creeping shrubs
Among the rocky areas, shrubs from the Fabaceae (legumes) and Asteraceae (composites) families stand out.
- Adesmia (Adesmia aspera, Adesmia volckmanii, Adesmia emarginata): Commonly known as "Paramelas," these are thorny shrubs with yellow flowers. They are critically important for fixing atmospheric nitrogen in the soil, enriching a volcanic substrate that is inherently poor in nutrients.
- Chuquiraga (Chuquiraga oppositifolia): Unmistakable for its intense yellow-orange flowers and its tough leaves ending in a spine. It is an emblematic species of the Maule mountain range.
3. The jewels of the heights: The violas.
Perhaps the most fascinating discovery for the attentive observer is the Rosy violets (Viola of the section AndiniumUnlike garden violets, these plants have evolved to camouflage themselves with the rocky environment. Their leaves are arranged in concentric rosettes, often with grayish or brownish colors that make them invisible to the untrained eye (a phenomenon known as crypsis).
Observation: They are often found in loose rock scree. They are considered species of high ornamental and scientific value, serving as indicators of the health of the Andean ecosystem.
Viola turritella. Joao de la Cruz.
Viola congesta. Joao de la Cruz.
4. Snow cacti
It is a common belief that cacti are exclusive to hot deserts. However, the genus [unclear] inhabits the Pehuenche Pass. Austrocactus (Austrocactus philippi). These cylindrical cacti with hooked spines spend much of the winter under the snow. Their ability to tolerate freezing is a physiological marvel.
Traditional Uses and Ethnobotany
The flora of the high Andes not only possesses ecological value, but has also been an integral part of the culture of muleteers, the Pehuenche people, and local communities for centuries. Knowledge of its properties has been passed down through generations.
Medicinal Use
- Pingo-Pingo (Ephedra chilensis): A gymnosperm shrub with jointed, green stems and no apparent leaves. Traditionally, an infusion of its stems is used as a diuretic and to cleanse the urinary tract and bladder. It is also attributed with stimulant properties.
- Bailahuén (Haplopappus sp.): Although more common at mid-altitudes, high-altitude varieties of this genus are used for their recognized digestive and liver properties, and as an antiseptic for wounds.
- Silver herb (Equisetum bogotense): Traditionally used as a hemostatic (to stop bleeding) and diuretic.
- Paramela (Adesmia ssp.): Used as a digestive system cleanser, ideally before eating meat, used together with mate.
Fuel Use
Historically, species that form hard cushions or woody shrubs (such as the Adesmia wave Llareta) were used as fuel by muleteers to cook and keep warm on cold mountain nights.
Storage Warning: Nowadays, It is strictly forbidden and discouraged to uproot these plants to make a fire. Its growth rate is extremely slow (millimeters per year), and the destruction of a llareta (Azorella sp.) It could mean the loss of centuries of growth.
Endemism and Biogeographical Uniqueness
The Laguna del Maule area is located in a vegetation transition zone. Here, elements of northern flora (Mediterranean Region) converge with elements of Patagonian and southern high Andean flora.
It is possible to find species of the genus Nassauvia, Cushion plants that resemble soft, green rocks, with small, fragrant white flowers. Some species of this genus are endemic to the Southern Andes, meaning they are found nowhere else on the planet. Likewise, some endemic species are present in the high Maule mountain range, such as Calceolaria pallida, Calceolaria williamsii or Phycella maulensis. Their presence is vital for high-altitude pollinators, such as native bees and butterflies adapted to the cold.
Calceolaria pallida. Joao de la Cruz.
Calceolaria williamsii. Joao de la Cruz.
An Inspiration for the Visitor
The vegetation of the Pehuenche Pass and the Maule Lagoon is a testament to resilience. It is not a desolate landscape, but a vast, vibrant ecosystem that operates at a different, slow, and persistent pace.
For those visiting the area, the recommendation is respectful observation. These species face a precarious balance; trampling off trails, the removal of souvenirs, or driving 4x4 vehicles across the steppe causes irreparable damage to soils that take decades to regenerate.
To admire a Viola camouflaged among the volcanic rocks, marvel at the copper flowers (Erythranthe sp.) in the waters of its Andean plains, or recognize the aroma of a Adesmia It's about connecting with the geological and biological history of the Andes. It's everyone's responsibility to preserve this natural heritage so that it continues to flourish in the highlands.
Erythranthe cuprea, A species that contrasts with the waters of the Andean slopes and the green vegetation of the floodplains. Joao de la Cruz.
High Andean wetland or “vega” in the Pehuenche Pass. Joao de la Cruz.
2 Responses
What beautiful work! And what lovely Calceoalaria plants you have!! Great job, Joao!!
Congratulations on such beautiful work, thank you for highlighting and caring about our Maule-Paso Pehuenche region. Thank you very much.