Fraxinus uhdei
(tropical ash)

Pictures

Picture	Title	Caption	Copyright
Title Tree Caption F. uhdei growing on the slopes of Mauna Loa island of Hawaii. Copyright A. Ares	Tree	F. uhdei growing on the slopes of Mauna Loa island of Hawaii.	A. Ares
Title Leaves and samaras of Fraxinus uhdei Caption Copyright A. Ares	Leaves and samaras of Fraxinus uhdei		A. Ares

Identity

Preferred Scientific Name

• Fraxinus uhdei (Wenz.) Lingelsh.

Preferred Common Name

• tropical ash

Other Scientific Names

• Fraxinus americana f. ovalifolia Wenz.
• Fraxinus americana var. uhdei Wenz.
• Fraxinus cavekiana Standl. & Steyerm.
• Fraxinus chiapensis Lundell
• Fraxinus hondurensis Standl.
• Fraxinus ovalifolia (Wenz.) Lingelsh.
• Fraxinus uhdei var. pseudoperiptera Lingelsh.

International Common Names

• English: Hawaiian ash; Mexican ash; Shamel ash
• Spanish: fresno; fresno blanco

Local Common Names

• Colombia: urapan

EPPO code

• FRXUH (Fraxinus uhdei)

Summary of Invasiveness

Fraxinus uhdei is a fast-growing, medium to large tree (up to 35-40 m tall and 1 m stem diameter) that grows naturally in mixed mountain forests from west-central Mexico to Costa Rica. It has been introduced to Hawaii, Puerto Rico and sub-Himalayan regions of India for watershed protection and timber production. It is also a popular street and shade tree in California, Arizona and Mexico. F. uhdei is shade tolerant and a prolific seed producer, and has become highly invasive in Hawaii where it has spread from cultivation into disturbed forest areas. It has been recorded as naturaized on the islands of Hawaii, Maui, Molokai and Oahu, where it has been included among the alien species most disruptive to native ecosystems. Invasions are more intense on fertile soils and along streams. In some stands of F. uhdei, understorey vegetation is almost completely absent, but stands with sparse canopies can harbour a profuse understorey of native and introduced species. Chemical control with a range of herbicides has proved to be very effective in Hawaii. Monitoring where introduced and replacement with native trees where naturalization is observed would reduce future risks.

Taxonomic Tree

• Domain: Eukaryota
•     Kingdom: Plantae
•         Phylum: Spermatophyta
•             Subphylum: Angiospermae
•                 Class: Dicotyledonae
•                     Order: Oleales
•                         Family: Oleaceae
•                             Genus: Fraxinus
•                                 Species: Fraxinus uhdei

Notes on Taxonomy and Nomenclature

Fraxinus is a large genus in the family Oleaceae, with 43 species native to temperate and subtropical regions of the northern hemisphere. Phylogenetic relationships among 40 of the 43 recognized species were estimated on the basis of nuclear ribosomal ITS sequences (Wallander, 2008). This research suggested that the previous subgenera and subsections be abandoned, and a new section established. A sectional key is presented in which the genus Fraxinus is divided into six sections: Dipetalae, Melioides, Pauciflorae, Sciadanthus, Fraxinus and Ornus. F. uhdei is placed in section Melioides (Endl.) Lingelsh.

Although two varieties of F. uhdei have been described, var. pseudoperiptera and var. typica, the Plant List (2013) recognizes no infraspecific taxa. The synonym F. americana var. uhdei Wenz. highlights the close relationship of F. uhdei and F. americana.

Fraxinus species are all commonly known as ash trees in English, with variants based on the species. The generic name is the Latin for ash tree, while the specific epithet uhdei honours Carl Uhde, a German plant collector who explored eastern Mexico in 1844-48 (Bracewell, 2005).

Description

Based on the description given by Wagner et al. (1999) as reported by PIER (2016), F. uhdei is a forest tree up to 35-40 m tall and up to 1 m in trunk diameter, with furrowed grey or brown bark, producing a canopy 9-13 m wide. Young branches are pubescent, soon glabrate. Leaves are 15-28(-30) cm long, compound and oppositely pinnate with 5-9 leaflets, (5-)7-11 cm long, 2-5 cm wide, upper surface dull green, glabrous, lower surface pale green, puberulent along midrib, margins irregularly serrulate, apex long-acuminate, base cuneate, petioles 6-10 cm long, petiolules 3-13 mm long. Flowers are unisexual (and the plants dioecious), in panicles 13-20 cm long; buds paired, covered with brown, finely pubescent scales; calyx minute, 4-toothed. Samaras are oblong-elliptic to oblong-oblanceolate, 2-4 cm long, the wing 5-6 mm wide, apex with a small notch. F. uhdei is sometimes referred to as an evergreen species but it is winter-deciduous in some regions.

Plant Type

Distribution

The native range of F. uhdei is commonly cited as mainland Central America, from Costa Rica, through Honduras and Guatemala to Mexico, and it is reported in many Mexican states north to Sinaloa, San Luis Potosi and Durango (USDA-ARS, 2016). McClintock (2001) also notes it in the Mexican states of Oaxaca and Chiapas; in Chiapas it has been observed in pine-oak-liquidambar forest, where it generally occurs along drier streams with other deciduous and semideciduous tree species.

USDA-ARS (2016) reports F. uhdei as native to Bolivia, but this is questionable. Records in the Missouri Botanical Garden (2015) confirm its presence in La Paz and Cochabamba; however, all these records are recent (2014-15) with a single other record from 2009. Thus, also noting the disjunct nature of these occurrences from the Central American native range, and that this species is widely planted as a street tree especially at higher altitudes, it is probable that the Bolivian records represent introductions. In her detailed work on the genus Fraxinus, Wallander (2008) also noted the presence of F. uhdei only in Central America (and Hawaii). F. uhdei (called ‘urapan’) is also recorded in Colombia (Bogota, Medellin, Pereira and Manizales) and Ecuador (Quito), where Fraxinus spp. are noted as widely planted in urban and rural settings in the Andes (Filguera et al., 2004). Thus, South American records are taken here as being introduced, and it is possible that it may be more widespread than reported. However, that the species is also possibly native to the Andean region cannot be discounted, and this assumption requires verification.

In the USA, F. uhdei is introduced, naturalized and invasive in Hawaii (PIER, 2016) and, more recently, in California (Hrusa et al., 2002; Calflora, 2016; USDA-NRCS, 2016). It is present but less common as a street tree in Arizona (Bricker and Stutz, 2005). F. uhdei is grown as an ornamental in Taiwan (Shen and Chen, 1993). As well as Hawaii, it has been introduced as a potential forestry species to Puerto Rico (Liogier and Martorell, 1982) and also India, where Shukla and Sangal (1980) reported on trial plantations established at Dehra Dun in the northern state of Uttarakhand (formerly Uttaranchal) in 1960. The India Biodiversity Portal (2016) has a single report (from 2015) of the species in a tropical moist deciduous forest near Dahanu in northwestern Maharashtra.

As an ornamental street tree, it is also possible that it is has been more widely introduced than is reported. 

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

According to Little and Skolmen (1989), F. uhdei was introduced to Hawaii from Mexico for use as a shade tree in the late 1800s, when two trees were planted on Oahu, one in Kalihi Valley and the other in Nuuanu Valley. These two trees are believed to be the seed sources for all the tropical ash planted in Hawaii. The Division of Forestry began planting this species for watershed cover about 1920 and subsequently planted over 700,000 trees on all the major islands. For a time in the early 1960s the species was extensively planted as a potential timber crop but was later found to have such poor form that it was dropped from consideration. The poor form may have resulted from inbreeding depression, since the entire population appears to have originated from the two parent trees.

However, weak wood strength was also noted in the species when it was introduced into the New Forest at Dehra Dun, northern India, in plantation trials established in 1960 (Shukla and Sangal, 1980).

F. uhdei, apart from tropical ash, is also commonly known as Shamel ash, named after Dr. Archie Shamel who first planted the trees in California in the 1920s, in Fairmont Park, Riverside, being a member of the Parks Commission there (McClintock, 2001).

Introductions

Risk of Introduction

F. uhdei is reported in a Pacific island risk assessment to be invasive or potentially invasive, with a high risk of invasion score of 11 (PIER, 2016). Acknowledging its use and value as an ornamental and street tree, as well as a forestry species, it is highly likely to be introduced further.

Habitat

In Hawaii, where F. uhdei is most invasive, it is observed commonly in forests and forest edges, rapidly colonizing disturbed forest areas (Weber, 2003). Invasions are also more intense on fertile soils and along streams (Harrington and Ewell, 1997). In Hawaii, it is an invasive at high altitude zones (PIER, 2016), but in California and elsewhere it also naturalizes at lower elevations.

It thrives in moist soil conditions, is typically confined to water courses and moist areas, but can survive arid conditions. In California where it is used as a street tree it appears to be spreading into canyons below mesas, and is also seen to be invading oak woodland as well as riparian and wetland areas (Council for Watershed Health, 2016).

Habitat List

Growth Stages

Biology and Ecology

Reproductive Biology

Section Melioides contains 15 American Fraxinus species, all dioecious trees with unisexual apetalous and wind-pollinated flowers (Wallander, 2001), though flowers of F. uhdei are known to be visited by bees, such as in Colombia (Obregon and Nates-Parra, 2014). F. uhdei regenerates rapidly from seed and trees coppice vigorously when cut and have also been reported to sucker.

Physiology and Phenology

F. uhdei trees are fast growing, reaching 7.5-10.5 m in 10 years. They are fire and shade tolerant; Pimienta-Barrios et al. (2012) report on the ecophysiological responses of F. uhdei to drought and recovery after rainfall. The species has also shown growth and physiological changes along an elevational gradient in Hawaii (Ares and Fownes, 2000).

When Gleason and Ares (2004) examined the physiological and morphological characteristics of Acacia koa (koa) and F. uhdei to understand the possible mechanisms facilitating invasion of koa forests in Hawaii uplands by F. uhdei, they found that F. uhdei was better able to survive defoliation than koa especially under high-light conditions, and seedlings allocated more carbon and nitrogen to storage, favouring their survival in high light under intense herbivory and on sites with seasonal or highly variable N availability. Ares and Fownes (2001) also reported on the competitive interactions between these two species.

F. uhdei is a deep-rooting species; roots in one study were seen to penetrate deeper than those of Quercus crassipes and Q. crassifolia. In fine-textured soil, F. uhdei root and shoot dry weight was significantly greater than in either Quercus species, but this was not the case in coarse-textured soil (Chacalo et al., 2000).

Regarding the chemical composition of plant parts, 18 compounds were isolated from the fruits, leaves and bark of F. uhdei, including secoiridoids, phenylpropanoids, lignans, phenylethanoids and triterpenoids, plus mannitol and β-sitosterol (Pérez-Castorena et al., 1997).

Longevity

Seeds of F. uhdei may remain viable in the soil for at least eight years (Council for Watershed Health, 2016).

Associations

In Mexico, F. uhdei is associated with the following forest plant communities: Quercus forest, pine forest, montane mesophyllic forest and gallery forest (Zepeda Dominguez, 2006). McClintock (2001) noted it in pine (Pinus) - oak (Quercus) - liquidambar (Liquidambar) forest in Chiapas. In the floodplain between Puebla and San Martín Texmelucan in the state of Puebla at an altitude of 2200 m, F. uhdei was found growing along watercourses in association with Alnus glabrata [Alnus acuminata subsp. glabrata], Salix bonplandiana, Buddleja cordata, Schinus molle and Populus species (Rzedowski, 2006).

In western North America F. uhdei is a food plant for larvae of several swallowtail butterflies, including Papilio eurymedon, P. multicaudata and P. rutulus (Calflora, 2016).

Environmental Requirements

F. uhdei is generally a species of subtropical upland areas up to 2750 m above sea level in Mexico, and also occasionally up to higher elevations in the Andes, to 3600 m in Bolivia (Missouri Botanical Garden, 2015), but it is also known to grow, but only rarely, in coastal areas. The species prefers higher rainfall zones, though tolerates dry seasons up to six months. Although it prefers light and fertile soils, according to Calflora (2016) it tolerates fine, medium or coarse soils and very slightly saline conditions. It prefers a soil pH of 5.7 to 7.6 and a temperature range of 4ºC in winter to 32ºC in summer. 

Climate

Latitude/Altitude Ranges

Air Temperature

Rainfall

Rainfall Regime

Soil Tolerances

Soil drainage

• free

Soil reaction

• acid
• neutral

Soil texture

• light
• medium

Special soil tolerances

• saline

Natural enemies

Notes on Natural Enemies

F. uhdei is attacked by two phytoplasmas, Phytoplasma asteris and Phytoplasma fraxini, causing ash yellows. Perilla-Henao et al. (2012) noted P. asteris for the first time on F. uhdei in Colombia, and Filgueira et al. (2004) provided the first confirmed record of ash yellows occurring outside North America, on F. uhdei in Colombia and Ecuador, with significance for Fraxinus species which are widely planted in urban and rural settings throughout the Andean range, as well as natural stands in Mexico. Testing in Arizona, USA, for the presence of ash decline showed symptoms of this phytoplasma disease (progressive tree dieback) on F. velutina but not on F. uhdei (Bricker and Stutz, 2005).

Foliar necrosis, related to the prevalence of Alternaria alternata, was observed in F. uhdei in Azcapotzalco, Mexico, and a potential association between the ash flower eriophyid (Aceria fraxiniflora) and the micromycete Fusarium sporotrichioides was also noted (Reséndiz Martínez et al., 2015).

F. uhdei is also a host to the glassy-winged sharpshooter (Homalodisca vitripennis) which is a vector for Pierce’s disease of grapevines caused by Xylella fastidiosa (Calflora, 2016).

Means of Movement and Dispersal

Natural Dispersal

F. uhdei samaras are dispersed by wind and water run-off, and possibly via storm drain systems (Council for Watershed Health, 2016). Trees can coppice vigorously from root and shoot sprouts (PIER, 2016).

Intentional Introduction

Tropical ash is widely grown as an ornamental and street tree in its native range, and is one of the most common trees in Mexico City, for example. Because of its value as an ornamental, it has been introduced to other countries such as the USA (Bricker and Stutz, 2005) and Taiwan (Shen and Chen, 1993). In Hawaii, it was introduced as a shade tree and then was widely planted as a forestry tree (Little and Skolmen, 1989; PIER, 2016), these plantations becoming the source of invasions into the wild.

Pathway Causes

Pathway Vectors

Impact Summary

Economic Impact

As a secondary host for H. vitripennis, a vector of Pierce’s disease (Calflora, 2016), the infestation and presence of F. uhdei near vineyards, particularly in California, could lead to disease outbreaks and consequent crop and economic losses. 

Environmental Impact

Impact on Habitats

Smith (1985) considers F. uhdei to be one of the 86 alien plant species most disruptive to native ecosystems in Hawaii because it can form single species stands. It can spread into disturbed forest areas and exhibits rapid growth, creating shade and outcompeting native plants. It germinates easily and prolifically, and is shade tolerant so can survive within existing native forest canopy (Council for Watershed Health, 2016).

In Hawaii, invasions have been recorded on the islands of Hawaii, Maui, Molokai and Oahu, where F. uhdei has been included among the species most disruptive to native forest ecosystems. F. uhdei is seen as a threat in particular in Kamakou Preserve, a rainforest in the mountains of East Molokai, and also in Waikamoi Preserve on the slopes of Mt. Haleakala in East Maui (Tunison, 1991). Invasions are more intense on fertile soils and along streams (Harrington and Ewell, 1997). In some stands, understorey vegetation is almost completely absent but stands with sparse canopies can harbour a profuse understorey of native and introduced species.

F. uhdei affects decomposition dynamics and nutrient turnover in montane Hawaiian rainforests (Rothstein et al., 2004). Compared to native species, it produces greater quantities of litter which is thinner, and has higher N and P concentrations and lower concentrations of lignin and soluble polyphenols. Microbes decomposing the litter produce fewer enzymes involved in N and P acquisition and more of those involved in cellulose degradation. Differences in litter quality and microbial activity result in a strong effect of litter type on rates of mass loss, and F. uhdei litter decomposes and releases nutrients at nearly twice the rate of Metrosideros litter regardless of site of decomposition. It is suggested that the large amounts of N and P in F. uhdei litter raise nutrient availability to decomposers in the forest floor, and the greater immobilization of N and P under an F. uhdei canopy may act as a governor on rates of nutrient cycling, limiting the degree to which F. uhdei invasion accelerates N and P cycling in this system (Rothstein et al., 2004).

Kagawa et al. (2009) found that forest water use was influenced by species composition, stem density, tree size, sapwood allocation and understorey contributions. In Hawaii, at the stand level, F. uhdei had nine times great water use than native M. polymorpha trees.

Impact on Biodiversity

Where invasive in Hawaii, several native species may be threatened in ecozones where F. uhdei has become naturalized. These include plant species in the genera Bidens, Calamagrostis, Cyanea, Cyrtandra, Geranium, Mucuna and Wikstroemia, as well as the tree snail Newcombia cumingi (US fish and Wildlife Service, 2012).

Native sandalwood trees on Hawaii are also threatened by competition from F. uhdei. Santalum haleakalae var. haleakalae is rare and restricted to Haleakala volcano on East Maui. S. haleakalae var. lanaiense, federally listed as endangered, occurs on the islands of Maui, Molokai and Lanai. Despite this wide distribution, seedlings are rarely, if ever, observed. It spreads locally via vegetative means by root sprouts when surface roots are damaged or exposed. Threats to both sandalwoods include competition for space, light, water and nutrients with alien plant species, including F. uhdei (Harbaugh et al., 2010).

Silene lanceolata is a short-lived perennial, federally listed as endangered, which is present on Hawaii, Oahu and Molokai. On Molokai it grows in Metrosideros polymorpha – Dodonaea viscosa – Leptecophylla tameiameiae shrubland on gulch slopes, ridge tops and cliffs in dry to mesic shrubland between 581 and 1043 m elevation. Habitat destruction by feral ungulates, fire and competition from invasive introduced plants such as F. uhdei, Lantana camara and Ricinus communis are immediate threats to S. lanceolata on that island (US Fish and Wildlife Service, 2010).

Threatened Species

Social Impact

Pollen from members of the Oleaceae, including Fraxinus, is a widespread cause of pollinosis. In tests carried out in Mexico City, F. uhdei was found to provide almost 30% of the total pollen load and was an important source of Oleaceae-associated aeroallergens in that city (Robledo-Retana et al., 2015).

Risk and Impact Factors

• Proved invasive outside its native range
• Tolerates, or benefits from, cultivation, browsing pressure, mutilation, fire etc
• Pioneering in disturbed areas
• Tolerant of shade
• Benefits from human association (i.e. it is a human commensal)
• Long lived
• Fast growing
• Has high reproductive potential
• Has propagules that can remain viable for more than one year
• Reproduces asexually

• Ecosystem change/ habitat alteration
• Modification of successional patterns
• Monoculture formation
• Negatively impacts forestry
• Negatively impacts human health
• Reduced native biodiversity
• Threat to/ loss of endangered species
• Threat to/ loss of native species

• Causes allergic responses
• Competition - monopolizing resources
• Competition - shading
• Rapid growth

• Highly likely to be transported internationally deliberately

Uses

Economic Value

As a timber tree, F. uhdei provides a valuable, medium density (0.5 g/cm³), pale brown wood with a straight grain and moderately fine texture (Shukla and Sangal, 1980). The wood is used mainly for cabinetwork, furniture, moulding and panelling, but it is also suitable for boat building, craftwood, flooring, interior trim, joinery poles, particleboards, pulpwood, plywood, structural sawnwood and veneer. It is easy to season, machine and finish but is susceptible to blue stain, Lyctus borers and termites. The sapwood is permeable to preservatives and the heartwood is moderately resistant.

In its native range, F. uhdei has been selectively logged but it is not a prime timber species. In Chiapas, Mexico, it has been grown in hedgerows for wood and fuel. In plantations, F. uhdei has high survival and rapid initial growth on favourable sites, but often exhibits uneven growth rates across sites, poor form and has a tendency to lodge. F. uhdei is relatively shade tolerant and can regenerate by coppicing (Walters and Wick, 1973). In Hawaii, F. uhdei has higher growth rates in relatively deep soils derived from volcanic ash than in shallow, stony organic soils. Timber yields in Hawaii and Puerto Rico have ranged between 4.1 and 11.5 m³/ha/year. 

Social Benefit

F. uhdei is planted as an ornamental street or shade tree in its native range and has been introduced as such in California, Hawaii and elsewhere. It is considered to have attractive leaves.

Uhdenoside, a secoiridoid dilactone isolated from leaves of F. uhdei, has potential applications in natural medicine (Shen et al., 1995).

Environmental Services

In the 1920s, F. uhdei was planted extensively in Hawaii for watershed protection (Harrington and Ewell, 1997).

Uses List

Environmental

• Amenity
• Landscape improvement
• Windbreak

Fuels

• Fuelwood

Materials

• Wood/timber

Medicinal, pharmaceutical

• Source of medicine/pharmaceutical

Ornamental

• garden plant

Wood Products

Boats

Furniture

Pulp

• Short-fibre pulp

Roundwood

• Pit props
• Posts
• Stakes

Sawn or hewn building timbers

• Carpentry/joinery (exterior/interior)
• Flooring
• For light construction
• Wall panelling

Veneers

Wood-based materials

• Fibreboard
• Hardboard
• Medium density fibreboard
• Particleboard
• Plywood

Woodware

• Cutlery
• Industrial and domestic woodware
• Sports equipment
• Tool handles
• Toys
• Turnery
• Wood carvings

Similarities to Other Species/Conditions

F. uhdei was originally described as a variety of F. americana, apparently based on similarities in samara morphology. The abaxial leaf surfaces of F. uhdei, however, lack the papillose cuticular structure characteristic of F. americana and its presumed closest relatives in eastern North America (Nesom, 2010). A channeled leaf axis and a smaller (2.5-4 cm long) samara also distinguish F. uhdei from F. americana.

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

The Council for Watershed Health (2016) suggests alternative species to F. uhdei for planting as street trees in areas where it has become invasive in California, including several native species.

Cultural Control and Sanitary Measures

When Friday et al. (2008) assessed whether disturbance from logging facilitated the spread of F. uhdei and other alien species beyond existing plantations on windward Mauna Kea on the island of Hawaii, they found that F. uhdei was able to regenerate following logging more rapidly than native tree species. Although basal area growth of F. uhdei was large enough to offset a decline in native trees and cause an increase in forest productivity, it was recommended that when F. uhdei plantations are harvested, forest managers should plan ways of favouring regeneration of the native Acacia koa, a species more valuable both for timber and for conservation.

Physical/Mechanical Control

Fraxinus trees coppice readily and can propagate vegetatively, so any mechanical control must also remove the roots. Manual or mechanical pulling of seedlings and small saplings is recommended by Tunison (1991).

Chemical Control

Tunison (1991) reports on research in Hawaii which found that undiluted triclopyr amine salt in a continuous ring notch application offered complete control of F. uhdei. Application of triclopyr to cut stumps was more practical for smaller trees. Lower concentrations than that recommended for notching were also effective. Control should begin with outlying plants and the edges of larger stands, progressing inwards toward the centre of the stand.

In other chemical control trials conducted in Hawaii, F. uhdei was controlled completely by cut-surface (continuous ring) applications of 2,4-D, dicamba, glyphosate or picloram. If applied in two notches in the trunk, all these herbicides except picloram also caused severe injury, but trees took 18 months to die. Better control was achieved if herbicide was applied in four drilled holes per tree and continuous ring notching, when using dicamba, glyphosate, metsulfuron or triclopyr. Good control was also reported with triclopyr ester in diesel oil applied to basal bark, and with undiluted triclopyr amine applied to frills, though only saplings were susceptible to triclopyr ester applied to basal bark (Motooka et al., 2002, 2003).

References

Ares A, Fownes JH, 2000. Productivity, nutrient and water-use efficiency of Eucalyptus saligna and Toona ciliata in Hawaii. Forest Ecology and Management, 139(1/3):227-236.

Ares A, Fownes JH, 2001. Productivity, resource use, and competitive interactions of Fraxinus uhdei in Hawaii uplands. Canadian Journal of Forest Research, 31(1):132-142.

Bracewell RN, 2005. Trees of Stanford and environs. Stanford, CA, USA: Stanford Historical Society, 306 pp. http://trees.stanford.edu/speciesindex.htm

Bricker JS, Stutz JC, 2005. Host range and distribution of the phytoplasma causing Arizona ash decline. Journal of Arboriculture, 31(5):257-262.

Bryan LW, Carlson NK, 1959. Hawaiian timber for the coming generations. Hawaii, USA: Bernice Puahi Bishop Estate.

Buck MG, Imoto RH, 1982. Growth of 11 introduced tree species on selected forest sites in Hawaii. USDA Forest Service Research Paper, Pacific Southwest Forest and Range Experiment Station, No. PSW-169, 12 pp.

Burgan RE, 1971. A spacing trial in tropical ash...an interim report. USDA Forest Service Research Note, Pacific Southwest Forest and Range Experiment Station, No. PSW-226, 3 pp.

Calflora, 2016. Information on California plants for education, research, and conservation. Berkeley, California, USA: Calflora Database. http://www.calflora.org

Carlson NK, Bryan LW, 1963. The Honaunau Forest: an appraisal after seven years of planting. Journal of Forestry, 61(9):643-647.

Chacalo A, Aldama A, Grabinsky J, 1994. Street tree inventory in Mexico City. Journal of Arboriculture, 20(4):222-226.

Chacalo A, Watson G, Bye R, Ordaz V, Aldama A, Javier Vázquez H, 2000. Root growth of Quercus crassifolia, Q. crassipes, and Fraxinus uhdei in 2 different soil types. Journal of Arboriculture, 26(1):30-37.

Charles Darwin Foundation, 2008. Database inventory of introduced plant species in the rural and urban zones of Galapagos. Galapagos, Ecuador: Charles Darwin Foundation.

Council for Watershed Health, 2016. Botanical name: Fraxinus uhdei. Weedwatch - Council for Watershed Health Invasive Plant Monitoring & Outreach Program. http://www.watershedhealth.org/weedwatch/docs/matrix/Fraxinus_uhdei_042207.pdf

Filgueira JJ, Franco-Lara L, Salcedo JE, Gaitan SL, Boa ER, 2004. Urapan (Fraxinus udhei) dieback, a new disease associated with a phytoplasma in Colombia. Plant Pathology, 53(4):520. http://www.blackwellpublishing.com/ppa

Francis JK, 1990. Fraxinus uhdei (Wenzig) Lingelsh. Fresno, tropical ash. Oleaceae. Olive family. USDA Forest Service, Southern Forest Experiment Station, Institute of Tropical Forestry, Miscellaneous Publication No. SO-ITF-SM-28, 4 pp.

Friday JB, Scowcroft PG, Ares A, 2008. Responses of native and invasive plant species to selective logging in an Acacia koa-Metrosideros polymorpha forest in Hawai'i. Applied Vegetation Science, 11(4):471-482. http://www.bioone.org/perlserv/?request=get-archive&issn=1402-2001

Gleason SM, Ares A, 2004. Photosynthesis, carbohydrate storage and survival of a native and an introduced tree species in relation to light and defoliation. Tree Physiology, 24(10):1087-1097.

Gould JR, Bellows TS, Paine TD, 1992. Evaluation of biological control of Siphoninus phillyreae (Haliday) by the parasitoid Encarsia partenopea (Walker), using life-table analysis. Biological Control, 2(4):257-265

Harbaugh DT, Oppenheimer HL, Wood KR, Wagner WL, 2010. Taxonomic revision of the endangered Hawaiian red-flowered sandalwoods (Santalum) and discovery of an ancient hybrid species. Systematic Botany, 35(4):827-838. http://www.bioone.org/doi/full/10.1600/036364410X539899

Harrington RA, Ewel JJ, 1997. Invasibility of tree plantations by native and non-indigenous plant species in Hawaii. Forest Ecology and Management, 99(1/2):153-162.

Haysom K, Murphy S, 2003. The status of invasiveness of forest tree species outside their natural habitat: a global review and discussion paper. Rome, Italy: FAO. http://www.fao.org/DOCREP/006/J1583E/J1583E00.htm

Hrusa F, Ertter B, Sanders A, Leppig G, Dean E, 2002. Catalogue of non-native vascular plants occurring spontaneously in California beyond those addressed in The Jepson Manual - Part I. Madroño, 49(2):61-98.

India Biodiversity Portal, 2016. Online Portal of India Biodiversity. http://indiabiodiversity.org/species/list

Jaakko P, 1999. Market research on commodity wood products from eight non-native, Hawaiian grown timber species. Report for the Hawaii Forestry Industry Association, Hawaii, USA. http://www.hawaii.gov/hfciforest/commodity.html.

Kagawa A, Sack L, Duarte K, James S, 2009. Hawaiian native forest conserves water relative to timber plantation: species and stand traits influence water use. Ecological Applications, 19(6):1429-1443. http://www.esajournals.org/doi/abs/10.1890/08-1704.1

Liogier HA, Martorell LF, 1982. Flora of Puerto Rico and adjacent islands: a systematic synopsis. Río Piedras, Puerto Rico: Editorial de la Universidad de Puerto Rico.

Little EL, Skolmen RG, 1989. Common forest trees of Hawaii (native and introduced). Agriculture Handbook No. 679. Washington, DC, USA: USDA Forest Service.

Mas Porras J, García Magana J, Prado Ortiz A, 1993. Trials of forest plantations in the Barranca de Cupatitzio Experimental Forest. [Ensayos de plantaciones forestales en el Campo Experimental Forestal 'Barranca de Cupatitzio'.]. Boletín Técnico - Instituto Nacional de Investigaciones Forestales y Agropecuarias, No. 108, 51 pp.

McClintock E, 1993. Shamel ash. Pacific Horticulture, 54:7-8.

McClintock E, 2001. The trees of Golden Gate Park and San Francisco. Berkeley, CA, USA: Heyday Books/Clapperstick Institute, 245 pp.

Missouri Botanical Garden, 2015. Tropicos database. St. Louis, Missouri, USA: Missouri Botanical Garden. http://www.tropicos.org/

Motooka P, Castro L, Nelson D, Nagai G, Ching L, 2003. Weeds of Hawaii's pastures and natural areas: an identification and management guide. Honolulu, HI, USA: College of Tropical Agriculture and Human Resources, University of Hawaii at Manoa, 184 pp.

Motooka P, Ching L, Nagai G, 2002. Herbicidal weed control methods for pasture and natural areas of Hawaii. Honolulu, Hawaii, USA: Cooperative Extension Service, College of Tropical Agriculture and Human Resources, University of Hawaii, 36 pp. http://www2.ctahr.hawaii.edu/oc/freepubs/pdf/wc-8.pdf

Nelson RE, Schubert TH, 1976. Adaptability of selected tree species planted in Hawaii forests. USDA Forest Service Resource Bulletin, Pacific Southwest Forest and Range Experiment Station, No. PSW-14, 22 pp.

Nesom GL, 2010. Fraxinus biltmoreana and Fraxinus smallii (Oleaceae), forest trees of the eastern United States. Phytoneuron, 51:1-30.

Obregon D, Nates-Parra G, 2014. Floral preference of Melipona eburnea Friese (Hymenoptera: Apidae) in a Colombian Andean region. Neotropical Entomology, 43(1):53-60. http://link.springer.com/article/10.1007%2Fs13744-013-0172-y

Pérez-Castorena AL, Escalona S, Núñez O, Romo de Vivar A, 1997. Constituents of fruits, leaves and bark of fresno (Fraxinus uhdei). Revista Latinoamericana de Química, 25(2):86-90.

Perilla-Henao LM, Dickinson M, Franco-Lara L, 2012. First report of 'Candidatus Phytoplasma asteris' affecting woody hosts (Fraxinus uhdei, Populus nigra, Pittosporum undulatum, and Croton spp.) in Colombia. Plant Disease, 96(9):1372. http://apsjournals.apsnet.org/loi/pdis

PIER, 2016. Pacific Island Ecosystems at Risk. Honolulu, USA: HEAR, University of Hawaii. http://www.hear.org/pier/index.html

Pimienta-Barrios E, Robles-Murguía C, Martínez-Chávez CC, 2012. Ecophysiological responses of native and exotic young trees to drought and rainfall. (Respuesta ecofisiológica de árboles jóvenes nativos y exóticos a sequía y lluvia.) Revista Fitotecnia Mexicana, 35(Numero especial 5):15-20. http://www.revistafitotecniamexicana.org/documentos/35-3_Especial_5/3a.pdf

Reséndiz Martínez JF, Guzmán Díaz L, Muñoz Viveros AL, Pascual Pola CNde, Olvera Coronel LP, 2015. Foliar diseases of the trees in the Tezozómoc Cultural and Recreational Park, Azcapotzalco, Distrito Federal. Revista Mexicana de Ciencias Forestales, 6(30):106-123. http://cienciasforestales.inifap.gob.mx/editorial/index.php/Forestales/article/view/4177/3448

Robledo-Retana T, Zenteno E, Agundis-Mata MC, Pereyra-Morales MA, Calderon-Segura ME, Calderon-Ezquerro MC, 2015. Detection of immunogens from Fraxinus spp. pollen grains. Aerobiologia, 31(3):403-410.

Rothstein DE, Vitousek PM, Simmons BL, 2004. An exotic tree alters decomposition and nutrient cycling in a Hawaiian montane forest. Ecosystems, 7(8):805-814. http://springerlink.metapress.com/app/home/contribution.asp?wasp=757ee397a8ba4588a307ad7080b53950&referrer=parent&backto=issue,3,6;journal,3,52;linkingpublicationresults,1:101552,1

Rzedowski J, 2006. Vegetation of Mexico. First digital edition (Vegetacion de Mexico. 1ra Edicion digital). Mexico City, Mexico: CONABIO, 504 pp. http://www.biodiversidad.gob.mx/publicaciones/librosDig/pdf/VegetacionMx_Cont.pdf

Shen YC, Chen CH, 1993. New secoiridoid dilactones from Fraxinus uhdei. Journal of Natural Products, 56(11):1905-1911.

Shen YC, Chen CY, Shen YC, 1995. Additional secoiridoid glucosides from Fraxinus uhdei. Planta Medica, 61:281-283.

Shukla NK, Sangal SK, 1980. A preliminary note on the physical and mechanical properties of Fraxinus uhdei grown at New Forest, Dehra Dun (U.P.). Indian Forester, 106(9):641-644.

Skolmen RG, 1974. Some woods of Hawaii - properties and uses of 16 commercial species. USDA Forest Service General Technical Report, Pacific Southwest Forest and Range Experiment Station, No. PSW-8, 30 pp.

Smith CW, 1985. Impact of alien plants on Hawaii's native biota. In: Hawaii's terrestrial ecosystems: preservation and management. Proceedings of a symposium held June 5-6, 1984, at Hawaii Volcanoes National Park. [ed. by Stone CP, Scott JM] Honolulu, HI, USA: University of Hawaii Press, 180-250.

The Plant List, 2013. The Plant List: a working list of all plant species. Version 1.1. London, UK: Royal Botanic Gardens, Kew. http://www.theplantlist.org

Tunison T, 1991. Element Stewardship Abstract for Fraxinus uhdei, tropical ash. Arlington, Virginia, USA: The Nature Conservancy, 5 pp. http://www.invasive.org/gist/esadocs/documnts/fraxuhd.pdf

US Fish and Wildlife Service, 2010. In: Silene lanceolata (no common name). 5-Year Review: Summary and Evaluation. US Fish and Wildlife Service, 15 pp.

US Fish and Wildlife Service, 2012. Endangered and threatened wildlife and plants; Listing 38 species on Molokai, Lanai, and Maui as endangered and designating critical habitat on Molokai, Lanai, Maui, and Kahoolawe for 135 Species; Proposed rule. Federal Register, 77(12, II):34464-34775. [50 CFR Part 17, RIN 1018-AX14.] https://www.gpo.gov/fdsys/pkg/FR-2012-06-11/pdf/2012-11484.pdf

USDA-ARS, 2016. Germplasm Resources Information Network (GRIN). National Plant Germplasm System. Online Database. Beltsville, Maryland, USA: National Germplasm Resources Laboratory. https://npgsweb.ars-grin.gov/gringlobal/taxon/taxonomysearch.aspx

USDA-NRCS, 2016. 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.

Wallander E, 2001. Evolution of wind-pollination in Fraxinus (Oleaceae) - an ecophylogenetic approach. PhD Thesis. Göteborg, Sweden: Göteborg University.

Wallander E, 2008. Systematics of Fraxinus (Oleaceae) and evolution of dioecy. Plant Systematics and Evolution, 273(1/2):25-49. http://www.springerlink.com/link.asp?id=104878

Walters GA, Wick HL, 1973. Coppicing to convert cull Australian Toon, Tropical Ash to acceptable trees. USDA Forest Service Research Note, Pacific Southwest Forest and Range Experiment Station, No. PSW-283, 4 pp.

Weber E, 2003. Invasive plant species of the world: A reference guide to environmental weeds. Wallingford, UK: CAB International, 548 pp.

Whitesell CD, 1976. Performance of seven introduced hardwood species on extremely stony mucks in Hawaii. USDA Forest Service Research Note, Pacific Southwest Forest and Range Experiment Station, No. PSW-309, 5 pp.

Whitesell CD, Wick HL, Honda N, 1971. Growth response of a thinned tropical ash stand in Hawaii...after 5 years. USDA Forest Service Research Note, Pacific Southwest Forest and Range Experiment Station, No. PSW-227, 3 pp.

Wick HL, Whitesell CD, 1969. Stump diameter affects sprout development of tropical ash. USDA Forest Service Research Note, Pacific Southwest Forest and Range Experiment Station, No. PSW-196, 3 pp.

Zepeda Dominguez H, 2006. Dominant forest species in an area of Contadero Forest (Especies dominantes forestales en un area del Bosque de Contadero). Undergraduate Thesis. Mexico City, Mexico: Universidad Autonoma Metropolitana, 35 pp.

Distribution References

Bricker J S, Stutz J C, 2005. Host range and distribution of the phytoplasma causing Arizona ash decline. Journal of Arboriculture. 31 (5), 257-262.

CABI, Undated. CABI Compendium: Status inferred from regional distribution. Wallingford, UK: CABI

CABI, Undated a. CABI Compendium: Status as determined by CABI editor. Wallingford, UK: CABI

Calflora, 2016. Information on California plants for education, research, and conservation., Berkeley, California, USA: Calflora Database. http://www.calflora.org

Charles Darwin Foundation, 2008. Database inventory of introduced plant species in the rural and urban zones of Galapagos., Galapagos, Ecuador: Charles Darwin Foundation.

Filgueira J J, Franco-Lara L, Salcedo J E, Gaitan S L, Boa E R, 2004. Urapan (Fraxinus udhei) dieback, a new disease associated with a phytoplasma in Colombia. Plant Pathology. 53 (4), 520. http://www.blackwellpublishing.com/ppa DOI:10.1111/j.1365-3059.2004.01030.x

Haysom K, Murphy S, 2003. The status of invasiveness of forest tree species outside their natural habitat: a global review and discussion paper. In: The status of invasiveness of forest tree species outside their natural habitat: a global review and discussion paper, Rome, Italy: FAO. http://www.fao.org/DOCREP/006/J1583E/J1583E00.htm#TopOfPage

Hrusa F, Ertter B, Sanders A, Leppig G, Dean E, 2002. Catalogue of non-native vascular plants occurring spontaneously in California beyond those addressed in The Jepson Manual - Part I. Madroño. 49 (2), 61-98.

India Biodiversity Portal, 2016. Online Portal of India Biodiversity., http://indiabiodiversity.org/species/list

Liogier H A, Martorell L F, 1982. Flora of Puerto Rico and adjacent islands: a systematic synopsis. Río Piedras, Puerto Rico: Editorial de la Universidad de Puerto Rico.

Missouri Botanical Garden, 2015. Tropicos database., St. Louis, Missouri, USA: Missouri Botanical Garden. http://www.tropicos.org/

Shen Y C, Chen C H, 1993. New secoiridoid dilactones from Fraxinus uhdei. Journal of Natural Products. 56 (11), 1905-1911. DOI:10.1021/np50101a006

Shukla N K, Sangal S K, 1980. A preliminary note on the physical and mechanical properties of Fraxinus uhdei grown at New Forest, Dehra Dun (U.P.). Indian Forester. 106 (9), 641-644.

USDA-ARS, 2016. Germplasm Resources Information Network (GRIN). Online Database. Beltsville, Maryland, USA: National Germplasm Resources Laboratory. https://npgsweb.ars-grin.gov/gringlobal/taxon/taxonomysimple.aspx

USDA-NRCS, 2016. The PLANTS Database. Greensboro, North Carolina, USA: National Plant Data Team. https://plants.sc.egov.usda.gov

Wagner W L, Herbst D R, Sohmer S H, 1999. Manual of the flowering plants of Hawai'i, Vols. 1 & 2. Honolulu, USA: University of Hawai'i Press/Bishop Museum Press. 1918 + [1] pp.

Contributors

20/01/2016 Invasive Species Compendium sections added by:

Nick Pasiecznik, Consultant, France

Distribution Maps