Furcraea macdougallii Matuda is at once the most spectacular and the most tragic member of its genus. Endemic to a tiny area of southern Oaxaca, Mexico, this arborescent succulent is the largest of all furcraeas — and of all agavoids in the broad sense — reaching trunk heights of 7 to 9 metres, topped by a rigidly upright rosette of blue-green, rough-textured leaves that gives it the silhouette of a cross between a giant agave and a small palm.
But the story of Furcraea macdougallii is above all a story of extinction. Classified Extinct in the Wild (EW) by the IUCN in 2020, the species has not been observed in its natural habitat since the last collections in the 1960s. Its original habitat was largely destroyed to make way for mezcal agave plantations. Today, Furcraea macdougallii survives only in cultivation: in a handful of botanical gardens around the world and as clonal village plantings near Santiago Chazumba in northern Oaxaca, where local people use it as living fences.
More troublingly still, all cultivated material worldwide appears to derive from a single clone — raising fundamental questions about the long-term genetic viability of the species and the practical possibility of reintroduction to the wild.
Taxonomy and nomenclature
Original description
Furcraea macdougallii was described in 1955 by the Japanese-Mexican botanist Eizi Matuda (1894–1978), from specimens collected by Thomas Baillie MacDougall in the Tehuantepec region of Oaxaca. The specific epithet honours this Scottish naturalist who explored the forests and deserts of southern Mexico for four decades. The correct spelling is macdougallii, with a double “l” — the frequent spelling macdougalii (single “l”) found in the horticultural trade is not a valid name under the International Code of Nomenclature.
Systematic position
Family Asparagaceae, subfamily Agavoideae. Furcraea macdougallii is placed in section Furcraea, alongside the other arborescent species Furcraea longaeva and Furcraea parmentieri. García-Mendoza (2000, 2001) treated it within his comprehensive revision of the arborescent Mexican furcraeas.
Thomas Baillie MacDougall (1895–1973)
The collector to whom the species is dedicated deserves mention. Born on the Isle of Bute, Scotland, MacDougall was a self-taught naturalist of remarkable tenacity who trained at the Manchester Botanical Garden and in forestry at Syracuse University (New York) before establishing himself as a nurseryman in the Bronx. Every winter from 1931 until his death in 1973, he explored the forests and arid zones of southern Mexico — principally Oaxaca and Chiapas. Known locally as “Don Tomás,” he documented fauna and flora of regions then virtually unknown to science. His field notebooks and some 5,000 photographs are held at the American Museum of Natural History. At least 21 plant species have been described in his honour, including Agave guiengola and Tillandsia macdougallii.
Common names
Falso Maguey Grande (Spanish, Oaxaca); Maguey de Pescadillo (referring to the use of leaves as fish poison); MacDougall’s Giant Century Plant, Tree Furcraea, Oaxacan Furcraea (English).
Morphological description
Habit
Furcraea macdougallii is an arborescent, evergreen, monocarpic succulent of exceptional dimensions. It develops a single, unbranched, massive trunk reaching 6–9 m in height and 30–70 cm in diameter — by far the tallest of any furcraea. In cultivation, dimensions are typically more modest: 2.5–4 m of trunk is more common in garden settings. The trunk is covered with the persistent fibrous bases of dead leaves, giving the bark a rough, textured character. When cleaned, the bare trunk has a highly ornamental appearance.
Leaves
The terminal rosette comprises 80–120 leaves, 140–180 cm long (up to 240 cm according to some horticultural sources) and 6–10 cm wide at the base, tapering towards the apex. Colour is a distinctive blue-green glaucous, and the leaf surface has a rough, almost “sharkskin” texture that is unique among cultivated furcraeas. The most striking morphological feature is the leaf orientation: all leaves are held rigidly upright, giving the rosette a columnar, vase-like silhouette that is unique in the genus. In Furcraea longaeva and Furcraea parmentieri, leaves spread or arch downward.
Leaf margins bear small, hooked teeth that are relatively inconspicuous on young plants but become more prominent with age. A short, rigid terminal spine caps each leaf.
Inflorescence and flowering
The inflorescence is a gigantic erect panicle reaching 5–9 m above the rosette. Total height (trunk + inflorescence) can approach 15–17 m: a specimen that flowered at the UCLA Botanical Garden (Mildred E. Mathias Garden) in 2011–2012 reached approximately 17 m. Flowers are white to greenish-white, pendulous, arranged in clusters along the branches of the panicle. Growth of the flowering stalk is remarkably rapid: the Kew specimen reached over 4 m in just a few weeks when it began flowering in October 2020.
Flowering in cultivation typically occurs after 25–40 years — sometimes more. In the natural habitat, the cycle was probably shorter due to more favourable conditions.
Bulbils and seeds
After flowering, the inflorescence produces abundant small bulbils along the stalk. These bulbils are the principal mode of propagation in cultivation. They fall to the ground in large numbers and root easily — which explains how MacDougall found clonal village populations derived from originally transplanted material.
In the original description, Matuda mentions the presence of numerous seeds, suggesting that the historical wild population was capable of sexual reproduction. However, the current situation — where all cultivated material probably derives from a single clone — makes viable seed production extremely unlikely due to probable self-incompatibility, a mechanism known in other Agavoideae (Rocha et al., 2006).
Distribution and natural habitat
Historical range
Furcraea macdougallii was a micro-endemic, restricted to a tiny area in the Yautepec district of Oaxaca state. The type locality lies near kilometre 713 of the Cristóbal Colón highway (Pan-American Highway), approximately 80 km northeast of Tehuantepec. García-Mendoza (1995) estimated the total distribution area at roughly 10,000 km² (a square of approximately 1° latitude × 1° longitude) — qualifying it as a micro-endemic under IUCN criteria.
Habitat
Dry deciduous thorn forests (selva baja caducifolia) on calcareous, stony soils between 750 and 1,800 m elevation. The climate is characterised by winter frosts that can be relatively severe, a dry spring, and sporadic summer rains — a typical seasonally dry tropical regime. The species shared its habitat with other xerophytes characteristic of the Tehuacán-Cuicatlán Valley, including numerous Agave, Cactaceae and Crassulaceae.
Conservation: Extinct in the Wild
| IUCN status | EW — Extinct in the Wild (assessed November 2019, published 2020) |
| Mexican status | “E” (probably extinct in the wild) under NOM-059-SEMARNAT-2010 |
Chronology of disappearance
The extinction of Furcraea macdougallii in the wild is relatively well documented thanks to MacDougall’s observations and subsequent fieldwork by García-Mendoza:
- 1953: MacDougall makes the type collection and observes 6 flowering plants at the type locality.
- 1955: 11 flowering plants recorded.
- 1961: only 5 flowering plants remain.
- 1965: last known collection at the type locality (by Howard Scott Gentry).
- After 1965: the species has never been found in the wild again despite targeted surveys.
Causes of extinction
The primary cause was habitat destruction for mezcal agave plantations. Southern Oaxaca is one of Mexico’s main mezcal-producing regions, and the conversion of dry thorn forest to Agave cultivation was particularly intense in the zone where Furcraea macdougallii grew. Fire likely played an aggravating role. The species’ extremely restricted distribution made it fatally vulnerable: as the IUCN notes, the last wild individuals could have been destroyed by minor, localised disturbances.
The single-clone problem
All cultivated Furcraea macdougallii worldwide — at Kew, the Huntington, UCLA, Singapore and elsewhere — appears to derive from a single clone: HBG 18137, distributed as ISI 459 (1965), ISI 1657 (1986) and ISI 90-59. This clone originated from MacDougall’s 1953 type collection at the Huntington Botanical Gardens.
If, as is probable, the species is self-incompatible (a mechanism common in Agavoideae), cross-pollination between genetically identical individuals cannot produce viable seeds. This fundamentally compromises any attempt at sexual reproduction and, by extension, any serious reintroduction programme. John Trager of the Huntington has confirmed the existence of a population around Santiago Chazumba in northern Oaxaca, probably clonal and derived from bulbils transported by local people for use as living fences — but DNA fingerprinting would be needed to confirm whether any genetic diversity exists.
History in cultivation
Huntington Botanical Gardens (California)
The Huntington is the repository of the original clone (HBG 18137). Specimen cultivated in the upper Desert Garden. Has flowered on multiple occasions over the decades, providing bulbils distributed to other institutions via ISI (International Succulent Introductions). In 2013, a flowering event allowed trios of bulbils to be offered for sale.
Royal Botanic Gardens, Kew (UK)
Kew received young plants from the Huntington in 1990. In October 2020, one specimen began to flower: the growth point became atypical, then an asparagus-like shoot developed, confirming the onset of the inflorescence. The stalk reached over 4 m in just weeks. This event was published in Curtis’s Botanical Magazine (Rees, 2023, Plate 1053).
UCLA Botanical Garden (California)
A specimen introduced in the 1980s via ISI flowered spectacularly in 2011–2012, reaching an estimated total height of approximately 17 m (trunk + inflorescence). The event surprised garden staff, as the plant had grown for decades without special care.
Other collections
Specimens exist in other gardens and private collections worldwide, including in Mediterranean Spain (a specimen in Valencia province was documented by van der Meer in 2014), Singapore (NParks), and Australia. Bulbils are sporadically available in the specialist trade.
Cultivation guide
| Hardiness | −3 to −6 °C / 21–27 °F (USDA zones 9a–11) |
| Light | Full sun to light shade |
| Soil | Very well-drained; calcareous appreciated |
| Water | Moderate; less water is better |
| Growth rate | Relatively fast for an arborescent agavoid |
| Flowering | Monocarpic, typically 25–40 years in cultivation |
Light requirements
Full sun, a minimum of six hours of direct sunlight daily. Tolerates light shade, especially in hot subtropical climates. In Mediterranean climates, a full-sun, south-facing position is ideal.
Soil and drainage
Excellent drainage is imperative. In the wild, Furcraea macdougallii grew on calcareous, stony, dry soils. In cultivation, use a sharply draining mix of garden soil and coarse mineral aggregate (50–70 % pumice, pozzolana or coarse sand). A slightly alkaline to neutral pH is appreciated. Root-zone waterlogging is the primary cause of mortality in cultivation.
Watering
Moderate, spaced watering. Extremely drought-tolerant once established. In Mediterranean climates with natural winter rainfall, supplementary irrigation is rarely needed except during prolonged spring or summer drought. In containers, water deeply then allow the substrate to dry completely. Reduce sharply in winter. Less water is better.
Cold hardiness
The cold tolerance of Furcraea macdougallii is estimated at −3 to −6 °C in dry, sheltered conditions. This makes it suitable for in-ground cultivation in the mildest Mediterranean coastal zones (coastal Côte d’Azur, coastal southern California, Mediterranean Spain, the Canary Islands), with winter protection during severe cold events. It is distinctly less hardy than Furcraea parmentieri (−8 to −12 °C) and Furcraea longaeva (−5 to −6 °C), but comparable to Furcraea selloa.
| USDA zone | Growing mode | Winter protection |
|---|---|---|
| 10–11 | In-ground, no issues | None |
| 9b | In-ground | Frost cloth on coldest nights |
| 9a | In-ground in sheltered, warm microclimate | Frost cloth + dry soil; overhead rain shelter helpful |
| 8b and below | Container | Overwinter in frost-free bright location |
Landscape use
Furcraea macdougallii is an architectural plant of the first rank. Its vertical, sculptural silhouette — a massive trunk topped by a rigidly upright rosette of blue-green leaves — is unique among agavoids and makes it an extraordinary specimen focal point for xeriscape, Mediterranean or exotic gardens. It pairs superbly with Agave, Yucca, columnar cacti, Dasylirion and palms. Even young, it makes a striking container plant, with its erect leaves providing a strong vertical element.
Propagation
By bulbils
The most common and reliable method. Bulbils form abundantly on the inflorescence after flowering. Harvest when a few centimetres long with root initials visible. Dry in shade for 24–48 hours before planting in a sandy, draining mix. Rooting is rapid in warm, bright conditions. This is how the species has been distributed to botanical gardens worldwide since the 1960s.
By basal offsets
Some specimens produce basal offsets at the base of the trunk. These can be separated when at least 15–20 cm tall. Less common than bulbil propagation.
By seed
Theoretically possible but currently unrealisable. Self-incompatibility (probable) and the absence of clonal diversity in cultivated material make viable seed production extremely unlikely. If fertile seeds were ever obtained (through crosses between different genotypes, if such genotypes exist), germination would proceed in a light, draining mix at 20–25 °C.
Pests and diseases
Root and crown rot
Caused by Phytophthora, Fusarium and Pythium. The main threat in cultivation. Prevention: impeccable drainage and rigorous irrigation management.
Mealybugs and scale insects
Colonise leaf bases, especially at the rosette heart where moisture is trapped. Paraffin oil or diluted soft soap controls moderate infestations.
Agave snout weevil
Scyphophorus acupunctatus, the major pest of cultivated agaves, may also attack Furcraea macdougallii. Larvae bore into the rosette heart and trunk, often causing death. Regular monitoring and pheromone trapping are recommended in regions where the weevil is present.
Frost damage
Frosted leaves become translucent, then brown and necrotic. Moderate frost affecting only outer leaves allows regeneration from the rosette heart. Severe or prolonged frost that destroys the apical meristem is fatal. Dry soil in winter dramatically improves cold survival.
Ethnobotany
Fish poison
The leaves are rich in steroidal saponins — natural surfactant compounds. Indigenous communities in Oaxaca used them as fish poison (barbasco): crushed leaves thrown into watercourses asphyxiate fish by disrupting gill function, causing them to float to the surface. This practice, attested by the vernacular name “Maguey de Pescadillo” (maguey of small fish), is shared with several other Furcraea and Agave species in tropical America.
Natural soap
The saponin-rich leaves produce detergent foam when crushed and mixed with water, and were used for washing clothes and personal hygiene.
Living fences
Around Santiago Chazumba (Oaxaca), Furcraea macdougallii is still cultivated as living fences (cerca viva). Plants arranged in rows form impenetrable barriers thanks to their spiny leaves. This mode of cultivation paradoxically constitutes one of the last refuges of the species.
Comparison with arborescent relatives
| Character | Furcraea macdougallii | Furcraea longaeva | Furcraea parmentieri |
|---|---|---|---|
| Maximum trunk height | 7–9 m (tallest) | 4–6 m | 3–5 m |
| Leaf orientation | Rigidly upright (columnar) | Arching, drooping | Arching to spreading |
| Leaf colour/texture | Blue-green, rough “sharkskin” | Green to blue-green, soft | Pale grey-blue, glaucous |
| Leaf length | 140–240 cm | Up to 150 cm | 50–70 cm |
| Inflorescence | 5–9 m (up to 17 m total) | Up to 13 m (record) | 5–6 m |
| Bulbils | Abundant | Typically absent | Prolific |
| Cold hardiness | −3 to −6 °C | −5 to −6 °C | −8 to −12 °C (hardiest) |
| IUCN status | Extinct in the Wild (EW) | Not evaluated | Not evaluated |
References
García-Mendoza, A.J. (2000). Revisión taxonómica de las especies arborescentes de Furcraea (Agavaceae) en México y Guatemala. Boletín de la Sociedad Botánica de México, 66, 113–129.
Martínez Salas, E., Samain, M.-S. & Fuentes, A.C.D. (2020). Furcraea macdougallii. The IUCN Red List of Threatened Species 2020: e.T136808736A137376234.
Meer, P. van der (2014). Furcraea macdougallii Matuda cultivada en la provincia de Valencia. Bouteloua, 17, 147–148.
Rees, A. (2023). 1053. Furcraea macdougallii Matuda: Asparagaceae. Curtis’s Botanical Magazine, 40(1), 25–34.
Rico-Arce, M.L. et al. (2015). The botanical collections of Thomas Baillie MacDougall (1895–1973): a legacy for the biodiversity of Mexico. Botanical Sciences, 93(2).
Rocha, M. et al. (2006). Pollination biology and adaptive radiation of Agavaceae, with special emphasis on the genus Agave. Aliso, 22, 329–344.
Smith, D. et al. (2023). Extinct in the wild: The precarious state of Earth’s most threatened group of species. Science, 379(6634), eadd2889.