Heterotheca grandiflora
(telegraph weed)

Pictures

Picture	Title	Caption	Copyright
Title Flowering habit Caption Heterotheca grandiflora (telegraph weed); flowering habit. Nr. Sliding Sands, Haleakala National Park, Maui, Hawaii, USA. October, 2007. Copyright ©Forest Starr & Kim Starr - CC BY 4.0	Flowering habit	Heterotheca grandiflora (telegraph weed); flowering habit. Nr. Sliding Sands, Haleakala National Park, Maui, Hawaii, USA. October, 2007.	©Forest Starr & Kim Starr - CC BY 4.0
Title Flowers Caption Heterotheca grandiflora (telegraph weed); flowers. Ka Moa o Pele, Haleakala National Park, Maui, Hawaii, USA. July 12, 2011. Copyright ©Forest Starr & Kim Starr - CC BY 4.0	Flowers	Heterotheca grandiflora (telegraph weed); flowers. Ka Moa o Pele, Haleakala National Park, Maui, Hawaii, USA. July 12, 2011.	©Forest Starr & Kim Starr - CC BY 4.0
Title Flowers Caption Heterotheca grandiflora (telegraph weed); close-up of flowers. Ka Moa o Pele, Haleakala National Park, Maui, Hawaii, USA. July 12, 2011. Copyright ©Forest Starr & Kim Starr - CC BY 4.0	Flowers	Heterotheca grandiflora (telegraph weed); close-up of flowers. Ka Moa o Pele, Haleakala National Park, Maui, Hawaii, USA. July 12, 2011.	©Forest Starr & Kim Starr - CC BY 4.0
Title Habit Caption Heterotheca grandiflora (telegraph weed); habit. Kula, Maui, Hawaii, USA. June, 2011. Copyright ©Forest Starr & Kim Starr - CC BY 4.0	Habit	Heterotheca grandiflora (telegraph weed); habit. Kula, Maui, Hawaii, USA. June, 2011.	©Forest Starr & Kim Starr - CC BY 4.0
Title Leaves Caption Heterotheca grandiflora (telegraph weed); leaves. Hawea Pl., Olinda, Maui, Hawaii, USA. July, 2013. Copyright ©Forest Starr & Kim Starr - CC BY 4.0	Leaves	Heterotheca grandiflora (telegraph weed); leaves. Hawea Pl., Olinda, Maui, Hawaii, USA. July, 2013.	©Forest Starr & Kim Starr - CC BY 4.0
Title Leaves Caption Heterotheca grandiflora (telegraph weed); close-up of leaves, note their hirsute surfaces. Hawea Pl., Olinda, Maui, Hawaii, USA. July, 2013. Copyright ©Forest Starr & Kim Starr - CC BY 4.0	Leaves	Heterotheca grandiflora (telegraph weed); close-up of leaves, note their hirsute surfaces. Hawea Pl., Olinda, Maui, Hawaii, USA. July, 2013.	©Forest Starr & Kim Starr - CC BY 4.0
Title Seedheads Caption Heterotheca grandiflora (telegraph weed); seedheads. D4, Kahoolawe, Maui County, Hawaii, USA. December, 2004. Copyright ©Forest Starr & Kim Starr - CC BY 4.0	Seedheads	Heterotheca grandiflora (telegraph weed); seedheads. D4, Kahoolawe, Maui County, Hawaii, USA. December, 2004.	©Forest Starr & Kim Starr - CC BY 4.0
Title Spent flower heads Caption Heterotheca grandiflora (telegraph weed); spent flower heads. D4, Kahoolawe, Maui County, Hawaii, USA. December, 2004. Copyright ©Forest Starr & Kim Starr - CC BY 4.0	Spent flower heads	Heterotheca grandiflora (telegraph weed); spent flower heads. D4, Kahoolawe, Maui County, Hawaii, USA. December, 2004.	©Forest Starr & Kim Starr - CC BY 4.0

Identity

Preferred Scientific Name

• Heterotheca grandiflora Nutt.

Preferred Common Name

• telegraph weed

Other Scientific Names

• Heterotheca floribunda Benth.

International Common Names

• English: silk-grass golden-aster; stinky daisy; telegraph plant; telegraphweed

Local Common Names

• Australia: stink daisy

Summary of Invasiveness

Heterotheca grandiflora is an annual or biennial herb native to arid coastal regions of North America, from California to northern Mexico. It produces large numbers of wind-dispersed seeds and is naturalized on all of the main Hawaiian Islands, USA, as well as in coastal regions of both New South Wales and south-east Queensland, Australia. In Hawaii it invades dry, disturbed sites from near sea level to over 2200 m elevation, forming dense cover and competing with native plants species including the endangered Schiedea hawaiiensis. In Australia, it is considered a potential or emerging environmental threat that invades and dominates disturbed sites and is designated a Class 2 weed in Queensland (Queensland Government, 2013).

Taxonomic Tree

• Domain: Eukaryota
•     Kingdom: Plantae
•         Phylum: Spermatophyta
•             Subphylum: Angiospermae
•                 Class: Dicotyledonae
•                     Order: Asterales
•                         Family: Asteraceae
•                             Genus: Heterotheca
•                                 Species: Heterotheca grandiflora

Notes on Taxonomy and Nomenclature

Heterotheca (family Asteraceae) is a genus of 25-30 species of annual or short-lived perennial herbs native to North America and Mexico. Members of the genus are taprooted or rhizomatous, often hispid-pilose, and usually aromatic or viscid (Kadereit and Jeffrey, 2010). The genus name Heterotheca is derived from the Greek heteros, which means 'different', and theke, 'case or ovary', referring to the differences between the ray and disc achenes (Wagner et al., 1999).

The origins of the common names 'telegraph weed' and 'telegraph plant' become apparent once H. grandiflora flowers, as its reproductive stems can reach heights of over 2 metres (Flora of North America Editorial Committee, 2015). Another common name 'stink daisy', refers to the pungent odour of the crushed leaves (Csurhes, 2009). 

Description

The following description is adapted from Wagner et al. (1999), DiTomaso and Healy (2007) and Flora of North America Editorial Committee (2015):

H. grandiflora is an aromatic annual or biennial herb. Stems reach heights of 0.5-2 m. Stems are stout and unbranched below the inflorescence, branched in the inflorescence, and coarsely hirsute and glandular pubescent above.

The leaves are ovate to oblong or oblanceolate, 2-8 cm long and 1-3.5 cm wide. The leaf surfaces are densely villous to hirsute, and the margins are coarsely serrate. Lower leaves have petioles 1-4 cm long. Upper leaves are sessile and often have stipule-like lobes at base.

Flower heads are several to numerous (10-110+) and in corymbiform arrays, becoming paniculiform with age. The involucres are 7-9 mm high. There are 25-35 bright yellow ray florets per head, and ray petals 4-6 mm long. The disc corollas are approximately 4 mm long. The pappus is yellowish brown to reddish with the outer series inconspicuous. There are two types of achenes which are both 2-5 mm long. The ray achenes are glabrous and slightly three-angled, and are lacking pappus bristles. The disc achenes are flattened and hairy, with tawny to orange-brown inner pappus bristles that are 3-5 mm long and with outer pappus scales 0.2-0.7 mm long. 

Distribution

H. grandiflora is native to southwestern North America, in coastal regions to 900 m elevation, from California to northern Mexico; it is probably introduced to Arizona, Nevada, and Utah (Flora of North America Editorial Committee, 2015), though considered as native to all four US states by USDA-NRCS (2015). It is recorded from all of the main Hawaiian Islands except Niihau (Wagner et al., 1999; Oppenheimer, 2010). In Australia, It has become naturalized in the lower Hunter Valley of New South Wales (Auld and Medd, 1987; Harden, 1992) as well as at the northern end of Queensland’s Gold Coast (Csurhes, 2009). It is reported as present in Japan, with no details on status or distribution (Mito and Uesugi, 2004). 

Distribution Table

The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.

History of Introduction and Spread

H. grandiflora was first collected on Maui, Hawaii, USA in 1909 (Wagner et al., 1999). The reasons for its introduction are unknown but it was presumably unintentional because there are no reported ornamental uses or other uses for the plant, and the collection location was in a remote, mountainous area far from human habitation. Subsequent collections were made on the islands of Kahoolawe and Lanai in 1913, Oahu in 1919, Hawaii Island in 1959, Kauai in 1971 and Molokai in 2008 (Bishop Museum, 2015). By 1966, it was reported as a weed of pastures, rangelands and cultivated areas (Haselwood and Motter, 1966).

The date of introduction into Australia is unknown, but H. grandiflora was documented as a common pasture, roadside and wasteland weed in the lower Hunter Valley of New South Wales in 1987 (Auld and Medd, 1987). In the early 1990s it was discovered on the Gold Coast in southeastern Queensland and, by 1998, was reported as common along roadsides and tracks on coastal sand dunes (Csurhes and Edwards, 1998; Queensland Government, 2013).

H. grandiflora is reported as "probably introduced" into Arizona, Nevada, and Utah, USA (Flora of North America Editorial Committee, 2015). Its introduction into Japan, where it is documented as present (Mito and Uesugi, 2004), is unknown.

H. grandiflora is common in California, USA, and is expanding its range, probably due to its ability to colonize disturbed areas such as roadsides, its flexible annual to biennial reproductive habit, and the multiple dispersal vectors of its dimorphic seeds (Flint and Palmblad, 1978).

Introductions

Risk of Introduction

Within its native range, H. grandiflora is promoted because it is beneficial to native pollinators (The Pollinator Partnership and NAPPC, 2008). Otherwise, there are no reported uses or commercially available sources of this plant and the probability of long-distance intentional or accidental introduction is low. 

Habitat

H. grandiflora is a weed of pastures, rangelands, cultivated areas and wastelands.

In its native range of coastal North America. H. grandiflora occurs in disturbed ground, along roadsides, and in vacant lots and fields from 0-100(-900) m elevation (Flora of North America Editorial Committee, 2015). In Hawaii it occurs in dry, disturbed areas from 10 to 2270 m elevation (Wagner et al., 1999).

In South East Queensland, H. grandiflora also invades disturbed or open, sparsely vegetated coastal sand dunes. Csurhes (2009) describes the habitat as harsh, wind-blown by sand and salt spray and with seasonally dry and hot conditions.

Habitat List

Biology and Ecology

Genetics

H. grandiflora has a chromosome count of 2n=18 (Flora of North America Editorial Committee, 2015).

Reproductive Biology

As an annual or biennial plant, H. grandiflora is able to flower after one to two years of growth (Wagner et al., 1999). After summer flowering in the first year, the plant dies back to the base, then re-sprouts and flowers again in the second year (Csurhes, 2009). In Queensland, Australia, peak seed production occurs in late summer and autumn (Csurhes, 2009). In California, USA, plants flower mostly during the summer, but can flower throughout the year depending on location, and seed germination occurs from autumn through to spring (DiTomaso and Healy, 2007).

Pollinator exclusion experiments demonstrate that plants are self-compatible, and capable of limited self-pollination, but seed set is improved in field settings (Flint, 1977). Flowers are visited and pollinated by a variety of generalist insects, including bees, beetles, flies and butterflies (Flint, 1977; The Pollinator Partnership and NAPPC, 2008).

As an annual to biennial plant, H. grandiflora persists for one to two years (Wagner et al., 1999). The disc achenes lack dormancy and will germinate whenever conditions are suitable. The harder coat of the ray achenes allows them to persist in the seed bank until the seed coat is worn down through abrasion, disturbance or other forms of scarification (DiTomaso and Healy, 2007).

Associations

In the Hawaiian Islands, H. grandiflora is now a common non-native component of subalpine shrubland at the base of Mau Kea, in the saddle between it and Mauna Loa on Hawaii Island. The community is dominated by the arborescent native shrub Chenopodium oahuense and scattered trees of Sophora chrysophylla and Myoporum sandwicense, with other weedy grasses and composites including Bromus rigidus, Nassella cernua, Tagetes minuta and Verbesina encelioides (Wagner et al., 1999).

H. grandiflora is also common in Sophora forest on Hawaii and East Maui, dominated by the native trees Sophorachrysophylla, and secondarily by Myoporum sandwicense, and with a number of weedy grasses and herbs including Bromus rigidus, Dactylis glomerata, Danthonia pilosa, Hypochoeris radicata and Verbascum thapsus (Wagner et al., 1999).

On the northeast slopes of East Maui and Mauna Loa, Hawaii, at 1680-1980 m elevation, H. grandiflora is a common component of subalpine mesic grasslands and shrublands, occurring with the native grass Deschampsia nubigena, the indigenous bracken fern Pteridium aquilinum and native shrubs consisting of Dubautia species and Leptecophylla tameiameiae. Other common weeds of this community type include the grasses Anthoxanthum odoratum, Dactylis glomerata, Festuca rubra, Holcus lanatus, and the herbs Cirsium vulgare, Hypochoerisradicata,Oenothera stricta and Verbascum thapsus (Wagner et al., 1999).

Environmental Requirements

The native range of H. grandiflora from California to northern Mexico has a temperate climate that is seasonally hot and dry. Within its naturalized range, including Hawaii, Australia, and probably Arizona, Utah and Nevada, it can tolerate climates that are tropical to sub-tropical and soils that are sandy, gravelly or otherwise well-drained (Csurhes, 2009; Flora of North America Editorial Committee, 2015). It also grows across a broad elevation range in the Hawaiian Islands, from 10 to 2270 m, demonstrating a measure of environmental versatility in the tropical to sub-tropical zone.

Climate

Latitude/Altitude Ranges

Air Temperature

Rainfall

Notes on Natural Enemies

There are no natural enemies or biological control agents currently known for H. grandiflora. In the Hawaiian Islands, Secusio extensa (Lepidoptera: Arctiidae) was evaluated as a potential biological control agent for Madagascar fireweed (Senecio madagascariensis) from the Asteraceae family, and H. grandiflora was one of the species evaluated, and found to be an unsuitable host in no-choice feeding tests (Ramadan et al., 2011).

H. grandiflora is reported to have low palatability to goats (Green and Newell, 1982) and is one of the few plants remaining in sparsely-vegetated areas otherwise heavily browsed by feral goats in Hawaii (Oppenheimer, 2010). 

Means of Movement and Dispersal

Natural Dispersal

H. grandiflora produces large numbers of achenes primarily dispersed by wind. The disc achenes have a bristly pappus that aids wind dispersal, whereas the ray achenes lack a pappus and generally fall beneath the parent plant (DiTomaso and Healy, 2007). Seeds may also be secondarily dispersed by water (Queensland Government, 2013).

Vector Transmission

Disc achenes may be secondarily dispersed by animals or people as their pappus bristles may allow them to adhere to fur or clothing (Csurhes, 2009).

Accidental Introduction

It is unknown how H. grandiflora was introduced into the Hawaiian Islands or Australia, but accidental introduction as a contaminant of soil or other materials is a possibility; this mode of transmission occurs locally within its naturalized range (Csurhes, 2009). On an Oahu military base in Hawaii, H. grandiflora was found growing out of sand which had been transported from an off-site location (Oahu Army Natural Resource Program, 2014).

It is also suspected of being moved by mud attached to machinery or other equipment, and its regular occurrence along roadsides and other heavily trafficked sites increases the probability of inadvertent dispersal (DiTomaso and Healy, 2007; Csurhes, 2009).

Intentional Introduction

Within its native range, H. grandiflora is promoted and may be intentionally planted because it is beneficial to native pollinators within the California coastal chaparral forest (The Pollinator Partnership and NAPPC, 2008). Otherwise, there are no reported uses or commercially available sources of this plant and so the probability of long-distance intentional or accidental introduction is low.

Impact Summary

Economic Impact

H. grandiflora is a potential weed of pastures, and due to its low palatability, may reduce the amount of forage available to livestock (Green and Newell, 1982). 

Environmental Impact

Impact on Habitats

As a ruderal weed of sparsely vegetated sites or other disturbed, open areas, H. grandiflora is unlikely to replace native vegetation or to have a significant impact on agriculture within the invaded range of Australia (Csurhes, 2009). In these sites, H. grandiflora is considered an emerging or potential environmental weed due to its rapid growth rate, prolific seed production and ability to form dense colonies on beaches, dunes and other open coastal plant communities (Queensland Government, 2013). It is unable to invade more shaded sites dominated by trees and shrubs (Csurhes, 2009).

Within its native range, it is typically only regarded as a weed when it occurs on agricultural land or landscaped areas (DiTomaso and Healy, 2007).

Impact on Biodiversity

In the Hawaiian Islands, H. grandiflora invades dry, disturbed areas that are generally lacking native cover, but at higher elevations of Maui and Hawaii Island it can form dense stands that may crowd out other plants (Medeiros et al., 1998; Wagner et al., 1999). It is able to colonize lava flows and potentially displace native colonizers (Daehler, 2005).

In the montane dry ecosystem of Hawaii Island, H. grandiflora is regarded as one of the primary weed threats to the endangered plant Schiedea hawaiiensis (Caryophyllaceae). This is because of its ability to grow quickly, form dense stands and inhibit native plant recruitment (US Fish and Wildlife Service, 2012; 2013).

Threatened Species

Social Impact

Dense stands of H. grandiflora, and the dead stalks left after flowering, could also impede movement or otherwise reduce the aesthetic beauty of invaded coastal or natural areas, and may therefore have a negative effect on tourism (Queensland Government, 2013).

Risk and Impact Factors

• Invasive in its native range
• Proved invasive outside its native range
• Abundant in its native range
• Is a habitat generalist
• Pioneering in disturbed areas
• Highly mobile locally
• Benefits from human association (i.e. it is a human commensal)
• Fast growing
• Has high reproductive potential
• Gregarious

• Monoculture formation
• Reduced native biodiversity
• Threat to/ loss of endangered species
• Threat to/ loss of native species

• Competition - monopolizing resources
• Competition - strangling
• Rapid growth

Detection and Inspection

H. grandiflora is included in the Weeds of Australia Lucid identification key (University of Queensland, 2013).

Similarities to Other Species/Conditions

In the Hawaiian Islands, H. grandiflora may be mistaken for Verbascum thapsus (common mullein), a herbaceous plant in the Scrophulariaceae family V. thapsus is also invasive at higher elevations, and has whitish hairy leaves and tall inflorescences that superficially look like H.grandiflora. H. grandiflora can be distinguished from V. thapsus by its dandelion-like flowers and by smaller leaves with pointed tips that have a distinctive, sage-like odour when crushed (Wagner et al., 1999).

Erigeron canadensis (horseweed) and Laennecia coulteri (Coulter's woolwort) are both members of the Asteraceae family with stem growth and flowering habit that also appear similar to H. grandiflora. Both of these taxa have white to cream-coloured flower heads, versus the bright yellow of H. grandiflora. The flowering stems of E. canadensis have leaves that are linear to narrowly lanceolate and the foliage lacks glandular hairs. 

Prevention and Control

Due to the variable regulations around (de)registration of pesticides, your national list of registered pesticides or relevant authority should be consulted to determine which products are legally allowed for use in your country when considering chemical control. Pesticides should always be used in a lawful manner, consistent with the product's label.

Prevention

In Australia, H. grandiflora is considered a potential or emerging environmental threat that can invade and dominate disturbed sites. It is designated a Class 2 weed in Queensland, requiring landowners to make efforts to control the plant on their property and prohibiting the sale of the plants or seeds within the state (Queensland Government, 2013).

Containment

To prevent further spread, an infestation of H. grandiflora, distributed over 200-300 hectares at the northern end of the Gold Coast in Queensland, Australia, has been the target of control efforts, but is otherwise regarded as probably beyond eradication (Csurhes and Edwards, 1998; Csurhes, 2009).

Physical/Mechanical Control

H. grandiflora can be hand-pulled, burned or mowed to prevent flowering (Smiley, 1922; DiTomaso and Healy, 2007). Cultivation may also deplete the seedbank by stimulating germination of the hard-coated ray achenes (DiTomaso and Healy, 2007).

Chemical Control

Herbicides are reported to provide effective control of H. grandiflora (Csurhes, 2009). Specific herbicides evaluated include 2,4-D amine (Zandstra et al., 2004; Willsher et al., 2008).

References

Auld BA, Medd RW, 1987. Weeds. An illustrated botanical guide to the weeds of Australia. Melbourne, Australia; Inkata Press, 255 pp.

Baldwin BG, Goldman DH, Keil DJ, Patterson R, Rasatti TJ, Wilken DH, 2012. The Jepson manual: vascular plants of California. Berkeley, California, USA: University of California Press.

Bishop Museum, 2015. Online database. Natural sciences collections. Honolulu, Hawaii, USA: Bishop Museum. http://nsdb.bishopmuseum.org/

Csurhes S, 2009. Weed risk assessment. Telegraph weed. Heterotheca grandiflora. Queensland, Australia: Department of Employment, Economic Development and Innovation, 12 pp.

Csurhes S, Edwards R, 1998. Potential environmental weeds in Australia: candidate species for preventative control. Canberra, Australia: Biodiversity Group, Environment Australia, 208 pp.

Daehler CC, 2005. Upper-montane plant invasions in the Hawaiian Islands: patterns and opportunities. Perspectives in Plant Ecology, Evolution and Systematics, 7(3):203-216.

DiTomaso JM, Healy EA, 2007. Weeds of California and other Western States. Vol 1. California, USA: UC Davis, 1808 pp. [University of California ANR Pub. 3488.]

Flint SD, 1977. Autoecology of the ruderal weed Heterotheca grandiflora with emphasis on germination dimorphism. Master of Science. All graduate theses and dissertations, 3768. Logan, Utah, USA: Utah State University. http://digitalcommons.usu.edu/etd/3768

Flint SD, Palmblad IG, 1978. Germination dimorphism and developmental flexibility in the ruderal weed Heterotheca grandiflora. Oecologia, 36(1):33-43.

Flora of North America Editorial Committee, 2015. Flora of North America North of Mexico. St. Louis, Missouri and Cambridge, Massachusetts, USA: Missouri Botanical Garden and Harvard University Herbaria. http://www.efloras.org/flora_page.aspx?flora_id=1

Green LR, Newell LA, 1982. Using goats to control brush regrowth on fuelbreaks. General Technical Report, Pacific Southwest Forest and Range Experiment Station, USDA Forest Service, No. PSW-59:iv + 13 pp.

Harden GH, 1992. Flora of New South Wales, Vol. 3. Kensington, NSW, Australia: New South Wales University Press.

Haselwood EL, Motter GG, 1966. Handbook of Hawaiian weeds [ed. by Haselwood EL, Motter GG]. Honolulu, HI, USA: Experiment Station/Hawaiian Sugar Planters' Association, 479 pp.

Kadereit JW, Jeffrey C, 2010. The families and genera of vascular plants. Flowering plants: Eudicots - Asterales, 8. Berlin, Heidelberg, New York: Springer-Verlag, 588 pp.

Medeiros AC, Loope LL, Chimera CG, 1998. Flowering plants and gymnosperms of Haleakala National Park. Hawaii, USA: University of Hawaii. http://manoa.hawaii.edu/hpicesu/techr/120.pdf

Mito T, Uesugi T, 2004. Invasive alien species in Japan: the status quo and the new regulation for prevention of their adverse effects. Global Environmental Research, 8(2):171-191.

Oahu Army Natural Resource Program, 2014. Status report for the Makua and Oahu implementation plans. Hawaii, USA: Pacific Cooperative Studies Unit, Schofield Barracks, 251 pp.

Oppenheimer H, 2010. New Hawaiian plant records from Maui County for 2008. Bishop Museum Occasional Papers, 107:33-40.

PIER, 2015. Pacific Islands Ecosystems at Risk. Honolulu, USA: HEAR, University of Hawaii. http://www.hear.org/pier/index.html

Queensland Government, 2013. Weeds of Australia. Biosecurity Queensland edition. Australia: University of Queensland. http://keyserver.lucidcentral.org/weeds/

Ramadan MM, Murai KT, Johnson T, 2011. Host range of Secusio extensa (Lepidoptera: Arctiidae), and potential for biological control of Senecio madagascariensis (Asteraceae). Journal of Applied Entomology, 135(4):269-284.

Smiley JF, 1922. Weeds of California and methods of Control. Sacramento, California: California State Printing Office.

The Pollinator Partnership and NAPPC, 2008. Selecting plants for pollinators. A regional guide for farmers, land managers, and gardeners in the California coastal chaparral forest and shrub province along the southern California coast. San Francisco, California, USA: The Pollinator Partnership/ North American Pollinator Protection Campaign, 24 pp.

US Fish and Wildlife Service, 1996. In: Big Island Plant Cluster Recovery Plan. US Fish and Wildlife Service, 202 pp.

US Fish and Wildlife Service, 2012. Endangered and threatened wildlife and plants; Listing 15 species on Hawaii Island as endangered and designating critical habitat for 3 species; proposed rule. Federal Register 77(201): 63927-64018. https://www.federalregister.gov/articles/2012/10/17/2012-24550/endangered-and-threatened-wildlife-and-plants-listing-15-species-on-hawaii-island-as-endangered-and

US Fish and Wildlife Service, 2013. Endangered and threatened wildlife and plants; Determination of endangered species status for 15 species on Hawaii Island; final rule. Federal Register, 78(209): 64637-64690. https://federalregister.gov/a/2013-24103

USDA-ARS, 2015. Germplasm Resources Information Network (GRIN). Online Database. Beltsville, Maryland, USA: National Germplasm Resources Laboratory. https://npgsweb.ars-grin.gov/gringlobal/taxon/taxonomysearch.aspx

USDA-NRCS, 2015. The PLANTS Database. Baton Rouge, USA: National Plant Data Center. http://plants.usda.gov/

Wagner WL, Herbst DR, Sohmer SH, 1999. Manual of the flowering plants of Hawaii. Revised edition. Honolulu, Hawaii, USA: University of Hawaii Press/Bishop Museum Press, 1919 pp.

Willsher L, Mason P, Whyte B, 2008. Preventing the spread of telegraph weed in South East Queensland. In: Proceedings of the 16th Australian Weeds Conference, Cairns Convention Centre, North Queensland, Australia, 18-22 May, 2008. Queensland, Australia: Queensland Weed Society, 67.

Zandstra B, Particka M, Masabni J, 2004. Guide to tolerance of crops and susceptibility of weeds to herbicides. Extension bulletin E-2833. http://www.uky.edu/Ag/Horticulture/masabni/xreflist/E-2833.pdf

Links to Websites

Organizations

USA: Haleakala National Park Resources Management - HALE RM, PO Box 369 Makawao HI 96768, http://www.nps.gov/hale/index.htm

Australia: Biosecurity Queensland Department of Agriculture, Fisheries and Forestry - DAFF, GPO Box 46, Brisbane QLD 4001, www.daf.qld.gov.au

Contributors

31/05/15 Original text by: 

Charles Chimera, Hawaii-Pacific Weed Risk Assessment, PO Box 983, Makawao, Hawaii 96768, USA

Distribution Maps