WESTERN A rborist Trees in the landscape, Part 3: Corymbia torelliana Donald R. Hodel

orymbia torelliana or Johnson 1995). Instead, larger, broad- Despite its tropical origins, the the blood-leaf gum is one of the er, bright green juvenile and interme- blood-leaf gum is an unusually adapt- C most distinctive and unusual diate leaves, not Eucalyptus-like at all, able species, tolerating some cold and eucalypts and one of the few that typically compose the canopy, even on performing well and making a hand- occurs naturally in and around rain reproductive trees. Adult leaves are some statement in the landscape. It forests. An unusually handsome tree typically narrower, more of a gray- does well near the coast and in the of typically fine conformation, it has green, and more Eucalyptus-like, but intermediate and inland valleys in an impressive, straight trunk covered are infrequently seen. Only very old southern California, and should prob- with attractive, smooth, green bark trees tend to have more adult leaves. ably be tried in the low deserts of the on the upper portions and branches, The large, terminal clusters of white Southwest. It would likely excel in and sports a stocking of dark, rough flowers, which can appear nearly year most places in Hawaii but could be- bark at the base. From a short distance round but be especially profuse in come a weed in moist and wet areas. it does not remind one of a eucalypt summer months, are a perfect comple- It tolerates harsh conditions, includ- at all. Indeed, its large, lush, tropi- ment to the lush, green foliage. ing some cold, heat, wind, smog, and cal-looking, bright green leaves and smooth bark conjure up images of a Ficus. However, the leaves are rough Despite its tropical origins, the to the touch, nearly like a fine sandpa- per, and close inspection reveals that blood-leaf gum is an unusually this tree is a eucalypt, albeit a most unusual one at that. adaptable species, tolerating some The large, lush, green leaves lend a tropical motif to the blood leaf gum, cold and performing well and but they are not adult leaves. In fact, making a handsome statement in adult leaves are rarely seen in the canopy (Boland 1984, Chippendale the landscape. 1988, Elliiot and Jones 1986, Hill and

aridity although regular irrigation in the summer is probably necessary in Join TAC the hotter interior areas. TAC or the Tree Advisory Committee enables everyone to share their Its strongly upright, broadly co- experiences and observations managing specific trees in our land- lumnar habit, impressive and attrac- scape and urban forests for this series Trees in the Landscape. TAC is tive trunk, tropical-looking foliage, free, easy to join, and open to everyone. Simply send me an e-mail and conspicuous if not showy flower expressing your desire to participate in TAC. I will e-mail all TAC clusters are sure to gain attention members notifying them which tree species I will be profiling in an wherever it is grown and make the upcoming issue of Western Arborist. TAC members can then respond blood-leaf gum a superb and much to me about their experiences and observations managing that tree. admired street, park, lawn, and shade Upcoming species to be covered in this series include Bombax ceiba, tree, specimen, accent, windbreak or Sapindus saponaria, Acacia pendula, and Alectryon excelsus, screen. among others. Corymbia torelliana Join TAC by e-mailing me: (F. Muell.) K. D. Hill and L. A. S. Johnson

Spring 2012 44 WESTERN A rborist

Figure 1. (Left) Corymbia torelliana is a handsome, solitary, medium to large, evergreen tree 45 to 90 feet tall. Unpruned and untrained trees in the open typically have branches and foliage nearly to ground (Fullerton Arboretum, Fullerton, CA). Figure 2. (Center) The trunk of Corymbia torelliana is impressive, straight, moderately stout, and generally of good form. Note the rough, dark bark below and the smooth, green bark above (Fullerton Arboretum, Fullerton, CA). Figure 3. (Right) Bark of Corymbia torelliana on the lower trunk is dark gray to black, persistent or flaky, fissured, and checkered (The Los Angeles County Arboretum and Botanical Garden, Arcadia, CA).

Taxonomy and history lyptus torelliana in 1877, basing it on a ately stout, generally of good form, to Synonyms: Eucalyptus torelliana F. collection that E. Fitzalan had made 3 feet in diameter, on older specimens Muell. in Trinity Bay, Queensland, Australia. bole to two-thirds of total height of Australian botanists K. D. Hill and L. tree (Fig. 2). Common names: blood-leaf gum A. S. Johnson erected Corymbia and (new red growth). Cadaga and cadaghi, transferred E. torelliana to it in 1995. Bark: on lower 3-10 feet of trunk dark both of which are names of Aboriginal gray to black, persistent or flaky, fis- origin. Description sured, checkered (Figs. 2-3); on up- The description is from several sourc- per trunk and branches deciduous Etymology: The genus name Corymbia es (Boland et al. 1984, Brooker and or shedding in thin sheets to become is derived from corym, a flower clus- Kleinig 2004, Chippendale 1988, Elliot smooth glossy green with slight glau- ter generally common to the group and Jones 1986, Hill and Johnson 1995, cous bloom (especially on young but where individual flower stalks arise Kelly et al. 1983, Muller and Haller reproductive trees) in summer (Figs. from different levels on the twigs but 2005) and from cultivated trees in 4-5), aging to slate-green or gray all flowers are held in more or less southern California. (especially on older trees) in winter the same plane. The specific epithet before again shedding. or species name torelliana honors Habit/Conformation: solitary, me- Count Luigi de Torelli, a member of dium to large, evergreen tree 45 to Leaves: simple; petiole to 1 inch the Italian senate who promoted the 90 feet tall, 15-40 feet wide, canopy long; new leaves often reddish and use of eucalypts to dry up the malarial mostly upright and broadly colum- with reddish hairs (Fig. 6); juvenile Pontine Marshes near Rome. Mueller nar, moderately dense, regularly to and intermediate leaves frequently named this species the year Torelli irregularly branched, unpruned and common in canopy of reproductive died to commemorate his life. untrained trees in the open typically trees; juvenile briefly opposite then have branches and foliage nearly to alternate, blade 2-8.5 × 2-5.5 inches, History: Australian botanist Ferdi- ground (Fig. 1). broadly ovate to ovate-lanceolate or nand von Mueller (1825-1896) named elliptic-lanceolate, light to dark green and described this species as Euca- Trunk: impressive, straight, moder- above, conspicuously pale below,

45 Spring 2012 WESTERN A rborist showy, terminal panicles to 2 × 2 feet (Fig. 10); peduncle 0.5-1.75 inches long; buds sessile, 0.2-0.35 ×0.1-0.25 inch, ovoid; operculum or lid 0.04-0.1 × 0.1-0.25, hemispheric or conic, dark brown; hypanthium or base greenish 0.25-0.3 × 0.15-0.3 inch, constricted proximally, urn-shaped; flower 0.8 inch wide when open, stamens as- cending to spreading, white (Fig. 11); mostly spring to fall.

Fruits: sessile, 0.35-0.6 × 0.15-0.3 inch, mostly urn-shaped or ovoid to nearly globular, woody, smooth; rim thick- ened, disc sunken, valves 3, enclosed (Fig. 12); seeds red-brown.

Distribution and ecology Corymbia torelliana is endemic to Queensland, Australia where it oc- Figure 4. (Upper left) Bark of Corymbia torelliana on the upper trunk and curs in a narrow band 30 to 50 miles branches is deciduous or shedding in thin sheets to become smooth glossy green wide stretching from north of Cairns (The Los Angeles County Arboretum and Botanical Garden, Arcadia, CA). south nearly to Townsville, from 16 Figure 5. (Upper center) Bark of Corymbia torelliana on the upper trunk and to 19 degrees south latitude and from branches is smooth, glossy green, and sometimes with a light glaucous bloom 100 to 2,500 feet elevation (Boland et (The Los Angeles County Arboretum and Botanical Garden, Arcadia, CA). al. 1984). The climate is warm-humid tropical with a distinct summer maxi- slightly hairy, rough to the touch; or lanceolate to narrowly or broadly mum rainfall pattern. Mean annual intermediate leaves alternate, 3.5-6.5 lanceolate, glossy green to gray- rainfall is about 60 inches with the × 1.5-3.5 inches, ovate to broadly green above, slightly paler below, maximum summer monthly rainfall lanceolate, light to dark green above, long-pointed, venation conspicuous about 16 inches. Mean maximum slightly paler below, slightly hairy (Fig. 9). temperature for the warmest sum- and rough to the touch but becom- mer months is about 86 F while the ing glabrous (Figs. 7-8); adult leaves Flowers: in 3 (-7)-flowered umbels mean minimum in the coolest winter alternate, 3-5.5 × 0.5-1.75 inches, ovate arranged in large, conspicuous, months is 54 to 59 F. Humidity is usu-

Figure 6. (Lower left) New leaves of Corymbia torelliana are often reddish and with reddish hairs (The Huntington Li- brary, Art Collections, and Botanic Gardens, San Marino, CA). Figure 7. (Lower right) Intermediate leaves of Corymbia torelliana are relatively large, dark green above and pale below (The Los Angeles County Arboretum and Botanical Garden, Arcadia, CA).

Spring 2012 46 WESTERN A rborist

Figure 8. (Upper left) Intermediate leaves of Corymbia torelliana are slightly hairy and rough to the touch but become glabrous and glossy (The Fullerton Arboretum, Fullerton, CA). Figure 9. (Upper right) Infrequently seen adult leaves of Corymbia torelliana are ovate or lanceolate to narrowly or broadly lanceolate, glossy green to gray-green, and long-pointed (East Alameda Plaza Park, Santa Barbara, CA). ally always high and frosts are rare Propagation and growth rate seedlings are sufficiently large to but occur in more inland and higher Corymbia torelliana is readily propa- be handled easily. Grow seedlings elevations of the range. gated from seeds, which germinate in light shade but acclimate to full Corymbia torelliana frequents in one to two weeks (Elliot and Jones sun quickly. Eucalypt seedlings and moist forests in and on the margins 1986). Select seeds from fully mature young plants typically grow quickly, of rain forests on the seaward slopes capsules (fruits), which typically so move them up to larger containers from the coastal plains up to the top attain maturity within one year of regularly to prevent kinked, circling, of the mountains to the west. Soils flowering. Immediately after collec- girdling, or otherwise poor root sys- are relatively deep, sandy loams tion sow seeds by scattering lightly tems that can be problematic later in with good drainage, adequate soil over a pre-moistened, clean, disease- the landscape. Peat pots/strips and moisture, and good moisture reten- free (pasteurized), well drained seed fluted gallon (and larger) containers tion (Boland et al. 1984). Companion or potting mix. Keep evenly moist can help to prevent such poor root trees include several other eucalypts, at a temperature of 70 to 80 F and characteristics. such as Eucalyptus tereticornis (forest protect from wind, dryness, and A relatively fast-growing species, red gum), and numerous rain forest extreme cold and heat. Transplant especially when young, Corymbia species. into individual containers when torelliana can attain about 50 feet in

Figure 10. (Lower left) Flowers of Corymbia torelliana occur in 3-(-7)-flowered umbels arranged in large, conspicuous, showy, terminal panicles (The Los Angeles County Arboretum and Botanical Garden, Arcadia, CA). Figure 11. (Lower right) Individual flowers ofCorymbia torelliana are 0.8 inch wide when open and have white, spreading stamens (The Los Angeles County Arboretum and Botanical Garden, Arcadia, CA).

47 Spring 2012 WESTERN A rborist height in 13 years in southern Cali- in southern California. However, it fertilizer would likely be beneficial. fornia’s Mediterranean climate. Plants might be intolerant of lower tem- Perhaps through judicious, mea- grown from seeds sown in 1998 at The peratures and this extreme cold will sured applications of fertilizers and Los Angeles County Arboretum and likely limit where it can be grown irrigation growth could actually be Botanic Garden in Arcadia, California successfully. retarded without losing quality. are now 45 to 55 feet tall, 25 to 35 feet Another drawback of Corymbia wide, and have trunks 11 to 14 inches torelliana might be its water require- Uses in diameter. Trees of similar size and ments. Elliott and Jones (1986) re- Corymbia torelliana would fill a variety age are at several botanical gardens ported that it thrived in well irrigated of uses in the urban forest and land- and parks in Southern California. situations and that regular irrigation scape and would be especially useful Growth rates in warmer, tropical and fertilizers promoted fast growth. as a street tree, park tree, shade tree, areas, like Hawaii, would likely be They also noted that C. torelliana suf- specimen, accent, and windbreak even faster. Trees planted as wind- fered in poor, clayey, shallow soils or screen. Its impressive, straight, breaks in Florida attained about 60 and performed much better on deep, upright trunk and relatively broadly feet in height after 20 years (Andreu well drained soils. However, trees of columnar conformation make for et al. 2009). this species in coastal and interme- a superb street tree, while its rapid diate valleys in southern California growth and dense canopy make it Environmental tolerances have performed adequately in a wide useful as a park and shade tree and There is little information about variety of soils and with moderate, as a windbreak. For street-tree use Corymbia torelliana and its environ- if not irregular, irrigation. Regular minimum parkway width and cut- mental tolerances; thus, we out size are probably five need to extrapolate informa- to six feet and trees must tion from its native habitat have lower branches re- and the few places where it moved to raise the canopy grows in southern Califor- for vehicular and pedestrian nia. It is not listed in Sunset clearance. Maintaining an (Brenzel 1995) but appears elevated canopy also allows adapted to Sunset Zones 18 the handsome trunk with through 24 in southern Cali- its smooth, green, attractive fornia and perhaps Zone 13 bark to be easily admired (low desert) in southwestern and appreciated. The im- California, eastern Arizona, pressive trunk, attractive and extreme southern Ne- bark, and large, dark green, vada. In northern California lush, tropical-looking leaves hard freezes and/or lack of make C. torelliana a striking, summer heat might restrict Figure 12. Fruits of Corymbia torelliana are mostly urn- if not eye-catching specimen growth but it should be eval- shaped, woody, smooth, and have a thickened rim (The and accent in the landscape. uated in Zones 15 through Los Angeles County Arboretum and Botanical Garden, The flowers, which can be 17 in the Bay Area. It might Arcadia, CA). profuse and cover nearly also perform adequately for the entire canopy, attract many years in Zone 12 in Arizona, irrigation, especially in the growing nectar-feeding birds and bees (Elliott gaining sufficient size before a hard season, though, would likely be more and Jones 1986). freeze, like the one of 2011, seriously critical in the hotter interior valleys damages or even kills it. Much of and low deserts. Pruning/management this area in the southwestern Unites A fairly tough and rugged spe- Corymbia torelliana has a strong ten- States falls within USDA Zones 9 to cies, it appears to tolerate some harsh dency for straight, upright growth and 11. It is likely to excel in most places conditions, including heat, wind, retention of lower branches and likely in Hawaii if there is adequate rainfall smog, and aridity. Its fast growth needs little training and pruning in or irrigation. Indeed, its potential to rate enables quick recovery during the nursery and landscape. Even if the become weedy would be a serious the growing season if damage does leader is broken, it will readily form concern there, (see below). occur. a new leader and continue upright Despite its tropical origins, Corym- There is no information about how growth. Provide adequate space in the bia torelliana is amazingly cold toler- Corymbia torelliana would perform in nursery and retain lower branches to ant, having withstood temperatures turf grass or groundcovers where it encourage maximum trunk caliper. in the middle 20s F with little or no might be over-irrigated and -fertil- Because of strong, straight, upright damage in the January 2007 freeze ized. However, regular water and growth, staking is probably mostly

Spring 2012 48 WESTERN A rborist unnecessary if trees are given ade- San Diego yet an adjacent C. citriodora, Availability quate space. Nursery trees might only with foliage intermingled with that of Despite its many attributes and need light pruning to reduce canopy C. torelliana, was heavily infested with popularity in other parts of the world, density and, when nearing readiness both pests. Corymbia torelliana is unknown in the for sale, to remove lower branches to nursery industries in California, Ari- elevate the canopy if desired. Once in Weed/invasive species risk zona, Nevada, and Hawaii. However, the landscape only judicious thinning Corymbia torelliana has become weedy it is easily propagated by seeds, which out to reduce canopy density might be in Australia outside its natural range can be procured from trees in south- necessary. ern California (see below) or Trees would benefit from from mail-order suppliers. regular irrigation and fertil- izer (Elliot and Jones 1986), Trees in California and especially during the grow- Hawaii ing season, but once estab- Corymbia torelliana is uncom- lished appear to perform mon in southern California. adequately in turf or non- A specimen of unknown turf areas with occasional age in East Alameda Plaza irrigation and no fertilizer. Park in Santa Barbara with However, regular irriga- an atypical, open canopy tion might be critical in hot composed of mostly adult interior valleys and the low leaves is about 50 feet tall, desert. 30 feet wide, and has a trunk 12 inches dbh (Fig. 13). The Problems/litter Huntington Library, Art Col- Corymbia torelliana is largely lections & Botanical Gardens free of serious problems. in San Marino has two trees, Its hard, dense wood is not the largest of which was prone to breakage, even in grown from seed in 1983 and high winds. Indeed, trees now is about 50 feet tall, 30 in San Marino and Arcadia, feet wide, and has a trunk 15 areas hard hit by the great inches dbh. The Los Angeles wind storm of November County Arboretum and Bo- 30-December 1, 2012, were tanic Garden in Arcadia has mostly defoliated yet had four specimens, three grown little or no branch break- from seeds in 1998 and one age. Old, mature trees can from seed in 1993; they are produce an abundance of Figure 13. Of unknown age, this specimen of Corymbia 40 to 55 feet tall, spread 15 flowers and subsequent torelliana in East Alameda Plaza Park with an atypical, to 35 feet, and have trunks 11 fruits. Because fruits are open canopy composed of mostly adult leaves is about 50 to 14 inches dbh (Fig. 14). A woody, hard, and rounded, feet tall, 30 feet wide, and has a trunk 12 inches DBH. single tree grown from seeds like those of many other in 2001 is now about 50 feet eucalypts and other species, they (Hill and Johnson 1995) and in Flor- tall, 25 feet wide, and has a trunk 11 may be problematic on smooth hard- ida (Matt Ritter pers. comm.), and inches dbh at the Fullerton Arbore- scape surfaces like driveways and is considered weedy in some of its tum at California State University in sidewalks. introduced range, mostly places Fullerton. A tree of unknown age near with a warm, humid climate. Thus the Balboa Park Carousel in Balboa Pests and diseases it is unlikely to become weedy in Park, San Diego is about 40 feet tall, Corymbia torelliana mostly has no se- places with a Mediterranean or arid 12 feet wide, and has a trunk 12 inches rious pests and diseases. Pests, such climate like California, Arizona, and dbh (Fig. 15). as psyllids and Eucalyptus tortoise Nevada. However, its weed risk is In Hawaii a number of trees of beetles, which plague species of the likely high in Hawaii, especially in Corymbia torelliana were planted in related Eucalyptus and Corymbia, are areas of higher rainfall, although its the Waiakea Forest Reserve on the unknown or little seen on C. torelliana current, official weed risk assessment Big Island in 1959 and a few might in California. For example, I observed for Pacific Islands, including Hawaii, be in public or private gardens but no damage from either of these two requires further evaluation (HEAR little is known about them (F. Starr pests on C. torelliana in Balboa Park, 2011, PIER 2011). pers. comm.).

49 Spring 2012 WESTERN A rborist 1995, Abasolo et al. 2011). Because it hybridizes with C. citriodora, C. torel- liana will likely also hybridize with C. maculata. The wood of Corymbia torelliana is hard, heavy, pale brown, and straight grained but subject to gum veins, and finds use in general construction (Elliott and Jones 1986, Penfold and Willis 1961). In Australia it once had commercial timber value but the tree is now too scarce. The flowers are attractive to bees and are useful for honey production (Elliot and Jones 1986).

Acknowledgements Several people shared informa- tion with me or showed me living specimens of Corymbia torelliana in southern California, including Kathy Figure 14. (Left) This specimen of Corymbia torelliana at The Los Angeles Musial, curator of living plants at The County Arboretum and Botanic Garden in Arcadia, CA was planted from seed Huntington Art Collections, Library, in 1998 and is now 50 feet tall, spreads for 35 feet, and has a trunk about 14 and Botanical Gardens in San Marino; inches DBH. Note the foliage nearly all the way to the ground. Susan Eubank, librarian, and James Figure 15. (Center) This specimen of Corymbia torelliana of unknown age near E. Henrich, botanist, both at the Los the carousel in Balboa Park, San Diego, CA is about 40 feet tall, spreads for 12 Angeles County Arboretum and Bo- feet, and has a trunk about one foot DBH. tanic Garden in Arcadia; Matt Ritter, author and botany professor at Cali- fornia Polytechnic State University Notes sia, Hawaii, California, Florida, and at San Luis Obispo and a well versed The eucalypts include about 700 spe- Australia (Andreu et al. 2009, ATRP and accomplished student of the cies comprising three genera, Eucalyp- 2011, Ellis and Brown 1984, Hill and eucalypts; Ken Greby, an unusually tus (ca. 600 species), Angophora (seven Johnson 1995, PIER 2011, Weeds Aus- knowledgeable arborist; and Chris species), and the recently segregated tralia 2011). In Australia it is one of the Barnhill, curator of living collections Corymbia (ca. 100 species). Angophora most commonly cultivated eucalypts at the Fullerton Arboretum. Robert differs from Eucalyptus and Corymbia in Brisbane and surrounding suburbs Hobdy, Forest Starr, and Joshlyn in its adult leaves oppositely arranged (Elliot and Jones 1986). Sand provided information about C. on the twigs and flowers having bris- Although Corymbia torelliana is of- torelliana in Hawaii. Matt Ritter, James tly glands interspersed with white ten found in rain forests, it may not be E. Henrich, and Ken Greby critically hairs and distinct sepal and petal a true rain forest species. It is thought reviewed the manuscript and offered lobes but lacking an operculum (cap that rain forest species have invaded valuable suggestions. or lid formed by sepals and petals that or advanced into adjacent Eucalyptus falls off as the flower opens).Corymbia forest where C. torelliana was growing Donald R. Hodel is the Environ- differs from Eucalyptus in its flowers (ATRP 2011, Boland 1984). mental and Landscape Horticul- arranged in corymbs, a structure Hybrids between Corymbia torel- ture Advisor for the University of where individual flower stalks arise liana and C. citriodora, the latter one California Cooperative Extension from different levels on the twigs but of the most common eucalypts in in Los Angeles, a position he has all flowers are held in more or less the California, have been reported in held for over 28 years. Don devel- same plane. Nigeria and Papua New Guinea (Ellis ops and implements educational Corymbia torelliana is widely cul- and Brown 1984). Hybrids between C. and applied research programs for tivated in warm areas around the torelliana and C. henryi, C. tesselaris, the professional tree and land- world for timber, windbreaks, and and C. citriodora have been reported scape management industries. He ornament, including Nigeria, Papua in Australia, the latter when it was specializes in the selection and New Guinea, Taiwan, China, Fiji, planted for timber near native stands management of trees and palms. Marquesas Islands in French Polyne- of C. torelliana (Hill and Johnson

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Literature cited Abasolo, M., D. Lee, and M. Shepherd. 2011. Spotting the spotted gum hybrids. CRC for Forestry. http:// www.crcforestry.com.au/view/index.aspx?id=75729. Accessed December 15, 2011. Andreu, M. G., B. Tamang, D. L. Rockwood, and M. H. Friedman. 2009. Potential woody species and species attributes for windbreaks in Florida. Univ. Florida I.F.A.S. Ext. Fact Sheet FOR224. Available on-line: http://edis.ifas.ufl.edu/pdffiles/FR/FR28600.pdf. ATRP. 2011.Australian Tropical Rainforest Plants. http://keys.trin.org.au:8080/key-server/data/ 0e0f0504-0103-430d-8004-060d07080d04/media/ Html/taxon/Corymbia_torelliana.htm. Accessed December 15, 2011. Boland, D. J., M. I. H. Brooker, G. M. Chippendale, N. Hall, B. P. M. Hyland, R. D. Johnston, D. A. Kleinig, and J. D. Turner. 1984. Forest Trees of Australia. CISRO, Melbourne, Australia. Brenzel, K. N. 1995. Sunset Western Garden Book. Sunset Publishing Corp., Menlo Park, CA. Brooker, M. I. H. and D. A. Kleinig 2004. Field Guide to Eucalypts. Vol. 3 (2nd ed.). Bloomings Books, Mel- bourne, Australia. Chippendale, G. M. 1988. Eucalyptus, Angophora (Myrtaceae). Flora of Australia, Vol. 19. Australian Government Printing Office, Canberra, Australia. Elliot, W. R. and D. L. Jones. 1986. Encyclopaedia of Australian Plants Suitable for Cultivation. Lothian Publishing Company, Ltd., Melbourne, Australia. Ellis, W. E. and A. G. Brown. 1984. Eucalypts for Wood Production. (CSIRO), Melbourne, Australia and Academic Press, Orlando, FL. HEAR. 2011. Hawaii Ecosystems at Risk Project. http://www.hear.org/. Accessed December 16, 2011. Hill, K. D. and L. A. S. Johnson. 1995. Systematic studies in the eucalypts 7. A revision of the blood- woods, genus Corymbia (Myrtaceae). Telopea 62: 185-504. Kelly, S. G. M. Chippendale, and R. D. Johnston. 1983. Eucalypts. Vol. 2. Van Nostrand Reinhold Co., New York, NY. Muller, R. N. and J. R. Haller. 2005. Trees of Santa Barbara. Santa Barbara Botanic Garden, Santa Bar- bara, CA. Penfield, A. R. and J. L. Willis. 1961. The Eucalypts. Botany, Cultivation, Chemistry, and Utilization. Leon- ard Hill, Ltd., London, and Intersciences Publishers, Inc., New York. PIER. 2011. Pacific Island Ecosystems at Risk. http:// www.hear.org/pier/species/eucalyptus_torelliana. htm. Accessed December 16, 2011. Weeds Australia. 2011. http://www.weeds.org.au/ cgi-bin/weedident.cgi?tpl=plant.tpl&state=&s=&ibra= all&card=T42. Accessed December 15, 2011.

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