Introduction & Discovery

Cyathea cooperi is the fastest-growing tree fern in cultivation, capable of adding 30–60 cm of trunk height per year under ideal conditions — a rate that dwarfs the 5–10 cm typical of the better-known Dicksonia antarctica. Ferdinand von Mueller first described the species in 1857 as Alsophila cooperi, based on collections from the subtropical rainforests of eastern Australia. He named it in honour of Sir Daniel Cooper (1821–1902), 1st Baronet of Woollahra, a prominent Sydney politician and patron of Australian botanical science who funded multiple collecting expeditions. Karl Domin transferred the species to Cyathea in 1929, reflecting a reclassification of the scaly tree ferns that placed all species with scales (paleae) on the stipe into Cyathea sensu lato. In its native range — the wet gullies and stream margins of Queensland and New South Wales — C. cooperi forms a conspicuous component of the mid-canopy, its crown of arching tripinnate fronds spanning 4–6 m at maturity. The combination of rapid growth, architectural drama, and relative cold tolerance (surviving brief frosts to −3°C) made this species the tree fern of choice for landscapers in California, the Mediterranean, coastal Britain, and New Zealand. It is now the most commercially propagated tree fern on Earth, sold in millions annually from tissue-culture laboratories in the Netherlands and Australia. That same vigour, however, has a dark side: C. cooperi is a declared invasive species in Hawaii, South Africa, and Lord Howe Island, where its prolific spore output and fast establishment allow it to displace native vegetation within a single decade.

A large tree fern native to rainforests in northeastern Australia with a slender trunk and a spreading crown of tripinnate fronds. One of the most popular tree ferns in cultivation and extremely fast growing.

Discovery & Naming

Ferdinand von Mueller, the Government Botanist of Victoria, first described this species in 1857 as Alsophila cooperi in his Fragmenta Phytographiae Australiae. Mueller's description was based on specimens collected in the subtropical rainforests of New South Wales and southern Queensland. He dedicated the species to Sir Daniel Cooper (1821–1902), 1st Baronet of Woollahra, a wealthy Sydney merchant and Speaker of the New South Wales Legislative Assembly who was a generous patron of Australian natural history — funding collecting expeditions and supporting the Australian Museum. The genus Alsophila, as used by Mueller, was one of several competing genera for scaly tree ferns in the 19th century. In 1929, the Czech botanist Karel Domin transferred the species to Cyathea in his monograph of the Cyatheaceae, reflecting the growing consensus that Alsophila (smooth-trunked, no paleae) and Cyathea (paleate stipes) should be kept separate. Modern molecular phylogenetics (Korall et al. 2007) supports keeping Cyathea as a large genus encompassing most paleate tree ferns, with Alsophila restricted to a smaller group — confirming Domin's transfer. Living plants of C. cooperi reached European glasshouses in the 1870s, transported as small trunks packed in damp sphagnum during the 6-week sea voyage from Sydney. The species quickly became a staple of Victorian ferneries — those elaborate glasshouse and rockwork constructions that were the height of horticultural fashion in 1860s–1890s Britain. By the early 20th century, it was grown outdoors in the Isles of Scilly, coastal Cornwall, and the Italian Riviera. The introduction to Hawaii (probably in the early 1900s as an ornamental) proved catastrophic: by the 1960s it was naturalised, and it is now classified as a noxious weed under Hawaii Revised Statutes Chapter 152.

Frond Morphology

Each frond of Cyathea cooperi is tripinnate — the lamina divides three times from the central rachis before reaching the ultimate segments (pinnulets). The stipe (the stem below the lamina) is 60–120 cm long, 3–5 cm in diameter at the base, and pale straw-green beneath a dense covering of golden-brown paleae. These paleae are narrowly lanceolate, 1–3 cm long, with entire margins and a paler central stripe; they detach readily when brushed, leaving the stipe with a distinctive pale, slightly scurfy appearance. The paleae are the single most important field character for separating C. cooperi from the sympatric C. australis: cooperi's scales are golden to tawny, australis's are dark brown to black and more firmly attached. The rachis is pale green, glabrous above but with scattered small scales beneath, slightly flexuose (gently zig-zagging at each pinna insertion). Pinnae number 15–25 per side, arranged alternately, the largest in the middle third of the frond reaching 30–60 cm long. Each pinna is once-pinnate, with 20–35 pinnules per side. Pinnules are lanceolate, 3–8 cm long, deeply lobed or pinnatifid, with an acute apex and an asymmetric base (the basiscopic side slightly wider). Fertile pinnules bear small round sori near the junction of each secondary vein with the costule; sterile pinnules in the upper crown tend to be slightly narrower with more deeply incised margins. The crozier (circinate vernation) is a tightly coiled spiral covered in golden-brown scales and pale hairs during unfurling — an attractive feature in its own right. A mature frond takes 4–6 weeks to unfurl fully from crozier to fully expanded lamina. Old fronds do not abscise cleanly; they break at the stipe base, leaving persistent stubs that gradually rot and are incorporated into the caudex surface.

Native Range & Distribution Map

Distribution map showing the native range of Cyathea cooperi.

Biology & Frond Morphology

The trunk of Cyathea cooperi is not true wood. It is a caudex — a composite structure of interwoven adventitious roots, old stipe bases, and fibrous tissue that builds upward as new fronds emerge from the apical meristem and old fronds senesce and break away. In cross-section, the caudex shows a central vascular cylinder (dictyostele) surrounded by a thick mantle of dark roots. Mature trunks reach 12–15 m in sheltered rainforest gullies, though 4–6 m is typical in cultivation. The trunk diameter is 15–25 cm, and the surface is rough with persistent stipe scars arranged in a spiral phyllotaxis. The crown carries 8–15 fronds simultaneously; each frond is tripinnate (three times divided), 3–6 m long, with a stout stipe 60–120 cm long. The stipe and rachis are the primary identification character: they are densely covered in golden-brown paleae (scales) that are narrowly lanceolate, 1–3 cm long, and easily detached — leaving a characteristic pale, scurfy residue on the hands when handled. This golden coloration immediately distinguishes C. cooperi from C. australis, whose paleae are dark brown to almost black. The pinnae are arranged alternately along the rachis, each 30–60 cm long, subdivided into pinnules 3–8 cm long. Sori are small (1–2 mm diameter), round, and positioned on the abaxial surface of fertile pinnules near the junction with the costule. The indusium is absent or reduced to a thin scale-like flap — a character of Cyathea section Cyathea. Spores are tetrahedral-globose, 30–40 μm, with a trilete mark. The chromosome number is 2n = 138, consistent with the paleopolyploid base of the Cyatheaceae. Root growth is continuous in warm conditions; the adventitious roots that form the caudex exterior can extend 30–50 cm into surrounding soil, but the root system is shallow and the plant relies heavily on trunk-surface moisture absorption.

Spore Dispersal

Cyathea cooperi reproduces exclusively by spores — there is no vegetative reproduction by offsets, rhizome division, or stolons. The sori are arranged in a regular pattern on the abaxial surface of fertile pinnules, each sorus positioned near the costule at the fork of a secondary vein. In C. cooperi, the indusium is absent or vestigial (reduced to a small, thin, membranous flap that is inconspicuous even under magnification) — this distinguishes it from genera like Cibotium that have well-developed bivalvate indusia. Each sorus contains 40–80 sporangia; each sporangium releases 64 spores via the annulus mechanism (a row of thickened cells that acts as a spring, catapulting spores when air humidity drops). Spores are tetrahedral-globose, 30–40 μm in diameter, with a prominent trilete scar, and are viable for 6–12 months under cool, dry storage. In still air, most spores fall within 10–20 m of the parent — tree ferns are generally poor long-distance dispersers compared to smaller filmy ferns. However, C. cooperi is a notable exception: its height (trunks to 12–15 m) places the spore-bearing fronds above the boundary layer in disturbed habitats, allowing wind to carry spores hundreds of metres. This wind dispersal, combined with the species' prolific sporulation (a single mature tree can produce billions of spores per season) and rapid gametophyte-to-sporophyte transition, explains its documented invasiveness. In Hawaii, C. cooperi spores have colonised volcanic substrates, lava flows, and roadside embankments — habitats devoid of competing native tree ferns. In South Africa's Western Cape, the species has invaded moist ravines in the Table Mountain National Park, forming dense stands that shade out indigenous Todea barbara and Blechnum capense. The gametophyte is a small, heart-shaped prothallus 5–10 mm across, photosynthetic, bisexual, and capable of self-fertilisation — further accelerating establishment in new territory.

Comparison with Similar Species

Cyathea cooperi vs Cyathea australis: the most common confusion in Australian horticulture. Cooperi has golden-brown, easily detached paleae on the stipe; australis has dark brown to black, firmly attached paleae. Cooperi grows 30–60 cm of trunk per year; australis grows 10–20 cm. Cooperi tolerates frost to −3°C; australis survives −8°C and is the better choice for UK and Pacific Northwest gardens. Cooperi's fronds are paler green and more finely divided; australis's are darker green and coarser. In the landscape, cooperi produces a taller, more slender trunk more quickly, while australis develops a sturdier, more textured trunk over time. Cyathea cooperi vs Dicksonia antarctica: the two most popular tree ferns in cultivation. Cooperi is faster (3–6x the growth rate), taller in maturity, and cheaper to buy as a young plant from spores or tissue culture. Dicksonia is far hardier (to −10°C with protection), has a thicker, fibrous trunk that can be transplanted as a bare log (it regenerates from the trunk — cooperi cannot), and is considered the gold standard for temperate gardens in Britain, Ireland, and the Pacific Northwest. Cooperi's golden stipe scales make it easy to distinguish from Dicksonia's brown-hairy stipes. Cyathea cooperi vs Cyathea medullaris: medullaris (the Mamaku or Black Tree Fern of New Zealand) has a diagnostic jet-black stipe and rachis, grows equally fast, and can reach 20 m in New Zealand forests. It is more tropical in requirements (−2°C is its limit, versus −3°C for cooperi) and is less widely available in the trade. Both are pioneer species with invasive potential outside their native range.

Reproduction & Propagation

Cyathea cooperi reproduces only by spores. It does not produce offsets, suckers, or rhizome divisions — the single apical meristem at the trunk tip is the sole growing point, and if it is destroyed, the plant dies. Spore collection: identify fertile fronds by the presence of brown sori on the underside of pinnules. Place a section of fertile frond in a paper bag and leave at room temperature for 2–3 days; the spores will shed as a fine brown dust. Sow spores immediately or store in a sealed container in the refrigerator (4°C) for up to 12 months. Sowing method: sterilise a shallow tray and fill with a 2 cm layer of finely milled peat or a 50:50 peat:perlite mix, moistened with boiled and cooled water. Scatter spores thinly and evenly on the surface — do not cover. Seal the tray in a clear plastic bag or propagator lid to maintain near-100 % humidity. Place under fluorescent or LED grow lights (12–16 hours daily) at 20–25°C. Germination occurs in 4–8 weeks as a green film of prothalli (gametophytes) on the substrate surface. The heart-shaped prothalli reach 5–10 mm across and produce both antheridia (sperm) and archegonia (eggs); a thin film of water on the surface is essential for fertilisation. After fertilisation, tiny sporophyte plantlets appear — these have simple, undivided fronds quite unlike the adult tripinnate form. Growth is very slow for the first 1–2 years. Transfer individual sporophytes to small pots of peaty, free-draining mix when they have 3–4 fronds and are 3–5 cm tall. Expect 3–5 years from spore sowing to a recognisable young tree fern with a 10–20 cm trunk. Commercial nurseries increasingly use tissue culture (micropropagation) to produce C. cooperi at scale, which reduces the juvenile phase to approximately 2 years.

Cultivation & Substrate

Cyathea cooperi is one of the most rewarding tree ferns for gardeners in USDA zones 9–11, and with protection it can survive in sheltered zone 8b sites. Site selection is critical: choose a position with dappled shade or morning sun only, sheltered from strong wind (which desiccates and tears the large fronds), and with naturally moist, humus-rich soil. Dig a hole 50 cm wider than the root ball and mix in generous quantities of composted bark, leaf mould, and aged manure. Plant so the crown (the point where fronds emerge) sits at or slightly above soil level — never bury the crown. Water deeply at planting and mulch the trunk base with 10–15 cm of bark chips or leaf litter to maintain soil moisture and cool root temperatures. In areas with dry summers (California, Mediterranean), overhead irrigation is highly beneficial: a drip emitter positioned at the top of the trunk, running for 30 minutes daily, mimics the rainforest mist that keeps the caudex exterior moist and promotes adventitious root growth. Without trunk moisture, growth slows and the lower trunk becomes bare and dry. Feed with a slow-release balanced fertiliser (14-14-14 Osmocote, 50–80 g) applied into the crown twice a year — spring and midsummer. Alternatively, monthly liquid feeding with half-strength 20-20-20 during the growing season gives excellent results. In containers, C. cooperi performs well for 3–5 years if given a large pot (60+ cm diameter), a free-draining mix of 40 % composted bark, 30 % peat or coir, 20 % perlite, and 10 % charcoal, and never allowed to dry out. Growth rate in cultivation varies with climate: 30–60 cm trunk height per year in subtropical zones (e.g., Brisbane, San Francisco Bay Area), 15–25 cm in cooler maritime climates (e.g., coastal UK), and near zero in cold winters where the crown goes dormant. Full sun is tolerated only where soil moisture is abundant and humidity is consistently above 60 %; in dry, exposed sun the fronds scorch within days.

Common Mistakes to Avoid

1. Planting in an exposed, windy site — C. cooperi fronds are large and brittle; persistent wind shreds them, reduces photosynthesis, and stunts growth. Solution: plant behind a wall, fence, or windbreak of evergreen shrubs. 2. Allowing the trunk to dry out completely — once the caudex exterior desiccates, the adventitious roots die and the apical meristem receives no water. If the crown dries fully, the plant is dead; unlike Dicksonia antarctica, cut or dried C. cooperi trunks do NOT re-sprout. Solution: overhead irrigation or daily trunk hosing in dry weather. 3. Full sun without adequate moisture — fronds scorch and brown within 48 hours of combined heat and drought stress. Solution: dappled shade, or full sun only with automated irrigation and humidity above 60 %. 4. Cold exposure below −5°C without protection — the crown is killed outright. Brief frost to −3°C is tolerable if the crown is dry, but wet frost is lethal. Solution: in borderline zones, wrap the crown and upper trunk in horticultural fleece from November to March. 5. Over-fertilising young plants (under 1 m tall) — concentrated fertiliser burns the shallow roots and can kill the growing tip. Solution: use half the adult rate for specimens under 1 m; liquid feed is safer than granular for small plants. 6. Planting too deep — burying the crown in soil causes immediate rot of the apical meristem. Solution: plant with the crown at or above soil level; mulch around but never over the crown. 7. Ignoring the paleae — the golden scales shed constantly and can irritate skin and eyes during pruning. Solution: wear gloves and eye protection when removing old fronds.

Seasonal Considerations

Spring (March–May in the Northern Hemisphere): the main growth flush begins as temperatures exceed 15°C. New croziers unfurl rapidly — expect 3–5 new fronds in quick succession. Apply the first slow-release fertiliser dose (50–80 g of 14-14-14 into the crown). Resume regular overhead watering if winter irrigation was reduced. Remove any fronds killed by winter cold — cut cleanly at the stipe base, leaving a 5 cm stub. Summer (June–August): peak growth period; the trunk elongates visibly. Water deeply 2–3 times per week in the absence of rain; overhead irrigation of the trunk is especially valuable now. Apply liquid feed monthly. Watch for scale insects on the stipe bases and treat promptly. Provide afternoon shade if temperatures regularly exceed 35°C — temporary shade cloth (50 %) can prevent frond scorch. Autumn (September–November): growth slows. Apply the second and final slow-release fertiliser dose in early September. Reduce overhead watering frequency. In borderline-hardy zones (USDA 8b–9a), begin preparing winter protection: check fleece wraps, position straw bales. Remove any broken or heavily damaged fronds to reduce wind resistance. Winter (December–February): in frost-free zones (10–11), the plant remains evergreen with minimal growth. Water monthly or as needed to prevent trunk desiccation. In zones 9a–9b, wrap the crown and upper 30 cm of trunk with two layers of horticultural fleece when frost is forecast. In zone 8b (sheltered only), the crown will likely die back; fill the crown hollow with dry straw and wrap the entire top 60 cm in fleece and plastic. If the crown is killed, the plant is dead — there is no regeneration from the trunk.

Diseases & Pests

Cyathea cooperi is generally robust and pest-resistant once established, but several issues can affect it. Scale insects (particularly Pinnaspis aspidistrae and Hemiberlesia lataniae) colonise the stipe bases and the underside of pinnae, appearing as small brown or white limpet-like bumps. Heavy infestations weaken the plant and cause yellowing of individual pinnae. Treatment: scrub off with a stiff brush dipped in dilute horticultural oil (2 % neem oil or white oil); severe cases may require imidacloprid systemic drench. Slugs and snails — Cornu aspersum and Deroceras reticulatum are particularly damaging — attack the unfurling croziers at night, chewing the soft tissue before it expands. Damage to a crozier results in a permanently deformed or hole-riddled frond. Prevention: copper tape around the trunk base, iron phosphate pellets, or nocturnal hand-picking. Phytophthora cinnamomi root rot is the most serious disease threat in poorly drained soils. Symptoms: yellowing fronds, wilting crown, blackened root tips, and eventually collapse of the entire plant. Prevention is the only practical approach: ensure excellent drainage, never plant in waterlogged clay, and avoid overwatering in winter. Crown rot (bacterial or fungal) occurs when water sits in the unfurling croziers during cold weather — the combination of cold and moisture rots the apical meristem. Prevention: in cold climates, tilt the crown slightly or cover it during prolonged wet-cold spells. Frond tip necrosis (browning of pinnule tips) is common in coastal areas with salt-laden wind and in areas with hard, alkaline irrigation water. Solution: use rainwater or softened water for overhead irrigation; provide a windbreak from salt spray.

Indoor Growing & Terrariums

Cyathea cooperi is not a houseplant in the conventional sense. It grows too large and too fast for any normal domestic room — within 3–5 years of planting, the trunk will reach 1.5–2 m and the frond crown will span 3–4 m. The only indoor settings where it thrives are large conservatories, heated glasshouses, and commercial atriums with ceilings of at least 4–5 m. In such spaces, it is spectacular: a single specimen creates an instant rainforest canopy effect. Requirements for indoor success: bright indirect light (minimum 3000 lux for 8+ hours daily), constant air humidity above 60 % (a challenge in heated buildings — use a large humidifier or grow alongside a water feature), temperatures of 15–28°C with no cold draughts, and a large container (minimum 60 cm diameter, 50 cm deep) with free-draining acidic substrate. Overhead misting of the trunk 2–3 times daily compensates for the lack of natural rainfall. Very young plants (under 50 cm, no visible trunk) can temporarily live indoors in a bright bathroom or humid kitchen for 1–2 years, but they must be moved outdoors or to a greenhouse before the frond span exceeds 1.5 m. Indoor plants are more susceptible to spider mites (Tetranychus urticae) due to low humidity — inspect the undersides of pinnules regularly and treat with neem oil if webbing appears.

Terrarium Setup

Cyathea cooperi is entirely unsuitable for terrariums. A mature specimen stands 4–6 m tall with a frond spread of up to 6 m — it is a landscape tree, not a tabletop plant. Even juvenile specimens grow rapidly and will outgrow any enclosed terrarium within 12–18 months. There are no dwarf cultivars small enough for terrarium culture. If you want a tree fern effect in a large vivarium or paludarium, consider Blechnum gibbum (a small, palm-like fern that stays under 1 m) or Selaginella species for a scaled-down prehistoric look. For greenhouse or conservatory culture, C. cooperi is outstanding — but the ceiling must be at least 4 m high, and ideally 6 m or more, to accommodate the full crown. Heated glasshouses in botanical gardens (Kew, Edinburgh, San Francisco) grow spectacular specimens that demonstrate the scale this species demands.

Landscape & Garden Use

Cyathea cooperi can be used in the garden wherever its hardiness and habitat preferences are matched. Ferns are classic choices for shaded borders, woodland gardens, stumperies, rockeries, stream-side plantings, and ground-cover under trees.

Landscape Tips

• Companions: Hostas, Astilbe, Heuchera, Tiarella, Epimedium, hellebores, snowdrops and other shade-tolerant perennials are classic partners.
• Soil preparation: Incorporate leaf mould or composted bark to improve moisture retention and mimic a forest floor.
• Mulching: A 3–5 cm mulch of chipped bark or leaf litter protects the rhizomes, conserves moisture, and slowly releases nutrients.
• Watering: Establish new plantings with regular deep watering during the first growing season; most hardy ferns need only occasional supplemental irrigation once established.

Conservation & Collector Notes

Cyathea cooperi is assessed as Least Concern by the IUCN (as Sphaeropteris cooperi in some databases, reflecting an alternative generic placement). It is common and widespread throughout its native range in eastern Australia, occurring in rainforest remnants, regrowth forest, and even urban bushland from Cairns to Wollongong. The species is not listed under Australian federal (EPBC Act) or state conservation legislation. Population trends are stable to increasing — the species actually benefits from forest fragmentation and disturbance, colonising road edges, cleared land, and secondary growth. The conservation story of C. cooperi is therefore primarily about its impact as an invasive species, not about its own protection. In Hawaii, it was introduced as an ornamental in the early 20th century, naturalised by the 1960s, and is now classified as a noxious weed. It forms dense stands in wet forests on Oahu, Maui, and the Big Island, displacing native Cibotium (hapu'u) tree ferns and preventing regeneration of native canopy trees. The Hawaii Department of Agriculture prohibits importation and encourages removal. In South Africa, C. cooperi is listed as a Category 1b invader under the National Environmental Management: Biodiversity Act (NEMBA), meaning it must be controlled and, where possible, eradicated. It has invaded moist kloofs (ravines) in the Western Cape and KwaZulu-Natal, outcompeting native Cyathea dregei, Todea barbara, and Blechnum species. On Lord Howe Island (an Australian World Heritage site), C. cooperi is an aggressive invader of the basalt-soil rainforest, threatening the endemic C. brevipinna. Eradication efforts on Lord Howe have been ongoing since the 2000s.

Collector Notes

Within the tree fern world, C. cooperi occupies the 'gateway species' niche — easy, fast, and widely available, it is where most collectors start. The natural progression leads to the following species for comparison and expansion. Cyathea australis (Rough Tree Fern): native to the same Australian forests, but immediately distinguishable by its dark brown to black paleae (versus golden in cooperi), slower growth rate (10–20 cm/year), rougher trunk surface, and greater cold tolerance (survives −8°C, two full zones hardier). Cyathea brownii (Norfolk Island Tree Fern): endemic to Norfolk Island, with a massive trunk to 20 m — the tallest tree fern species. Rare in cultivation but occasionally available from specialist nurseries. Cyathea medullaris (Mamaku, Black Tree Fern): from New Zealand, distinctive for its jet-black stipe and rachis and very fast growth rivalling cooperi. More frost-tender (−2°C maximum). Cyathea dealbata (Silver Fern): the New Zealand emblem, with striking white-silver undersides to the fronds. Slow-growing and challenging in cultivation. Named cultivars of C. cooperi exist but are poorly documented: 'Brentwood' is reported as a more compact form with shorter stipes, and 'Robusta' is a vigorous selection from southeast Queensland. Be aware that C. cooperi is a declared invasive weed in Hawaii (prohibited), South Africa (NEMBA Category 1b — must be controlled and destroyed), and Lord Howe Island. Check local regulations before planting, and in mild-climate gardens, remove fertile fronds before spore release to prevent naturalisation.

Ethnobotany & Cultural Significance

Aboriginal Australians of the east-coast rainforest regions utilised tree fern trunks as a carbohydrate source. The starchy pith of the caudex — the central core surrounded by the vascular cylinder — was extracted by splitting the trunk longitudinally, scraping out the white pith, and roasting or baking it in earth ovens. The pith is low in protein but rich in starch and was an emergency food rather than a dietary staple. Fronds of Cyathea and Dicksonia were used to line cooking pits and as temporary roofing material for shelters. The fibrous outer mantle of the trunk (composed of interwoven adventitious roots) was used by early European settlers as a building material: slabs of tree-fern trunk were cut and stacked to form walls of bush huts, garden borders, and even fences — a practice still seen in rural Tasmania and New Zealand, though now using sustainably harvested Dicksonia rather than Cyathea. In modern horticulture, Cyathea cooperi is the single most commercially important tree fern species globally. Millions of plants are produced annually by tissue-culture laboratories, primarily in the Netherlands, Australia, and Costa Rica. It is the standard tree fern of resort landscaping in tropical and subtropical tourism destinations. , unlike Dicksonia antarctica, a felled or cut C. cooperi trunk will NOT regenerate. The apical meristem is the sole growing point; if it is removed or killed, the plant dies. This means there is no sustainable wild-harvest industry for C. cooperi trunks — all commercial supply comes from nursery-raised plants.

Frequently Asked Questions