The Burnley Plant Guide (BPG) had its origins in 1990 when the then Victorian College of Agriculture and Horticulture (Burnley College) received a grant from TAFE to assist in the development of computer-based plant identification teaching. Our aim was to develop a teaching aid that would allow the teaching of horticultural plants, regardless of season and weather, and with high quality images that would assist with plant identification. It was not intended to replace living specimens, but to complement them and provide a learning resource to staff and students.
Our colleague, Nick Bailey, gave invaluable assistance in applying for the grant and providing information on the computer technology and software that would make our objectives reality. Other staff at Burnley rallied to the project with Professor James Hitchmough willingly contributing his plant data sheets, and Jill Kellow preparing images and data sheets. A group of teaching staff, and many students and former students contributed information and images.
By 1995 progress had been made, with 1000 rather than 600 plants the target, but we had not achieved our goal of a version that worked for students, industry and the public. Fortunately Jill Kellow, with the support of Dr Mike Looker, expanded her input to the project dedicating a commitment of time and effort that we had no right to expect but which made completion a reality. Kevin Blazé demonstrated a similar dedication to the computer and software aspects of the work. Without their outstanding contributions, the first version of the Burnley Plant Guide would never have reached completion.
The BPG proved to be a highly successful teaching tool and in 2011 we decided to make it available as an online, searchable, database for students to access at anytime and from anywhere. Initially the test version of this product will be available for students in 2012 and their feedback will be essential to help us refine it. Ultimately the database will be available as a publicly accessible website.
The development of this online version of the BPG has been a joint project between a team at the Melbourne School of Land and Environment (Jenny Bear, Jill Kellow and John Rayner) and a team at Learning Environments (David Adam, Gordon Yau, David Vasjuta and Josella Rye). We are especially indebted to Jenny Bear and David Adam for excellent leadership in its development and Jill Kellow for her unstinting diligence and dedication in continuously improving the database over more than 20 years. It is largely due to Jill that, in 2012, the BPG contains horticultural information on more than 2700 plants specific to South-eastern Australia and more than 7500 images.
All involved with the BPG have waived their rights to royalties or fees. Their commitment has been to produce a learning package useful to horticulturists, landscapers and gardeners. We thank all the staff and students who have shared the vision of the BPG and who have given generously of their time, images and information.
Dr Greg Moore, Principal of Burnley Campus (1988-2007), Head, School of Resource Management and Geography (2002-2007)
Associate Professor Stefan Arndt, Director of Burnley Campus (2011-present)
The Burnley Plant Guide (BPG) is an indexed, searchable database of plants that has been developed to support the learning of plants by students at the University of Melbourne, particularly those who undertake courses at its Burnley Campus. The database contains information on over 2,700 plant species or cultivars, and more than 7,500 images illustrating plant recognition characters, plant habitat, form, and use in the landscape. The plants included are based on those taught in undergraduate and postgraduate subjects and are for the most part, common in cultivation in south-eastern Australia. As well as landscape plants, the BPG contains a limited number of horticultural and environmental weeds while, to enrich student experience, and for general interest, a number of less common exotic and Australian plants have also been included.
In previous versions, landscape plants, wild plants and weeds were not separated in the searches. In this version, a new search category “plant group” has been included to enable users to retrieve a list of landscape and garden plants that does not include weeds or plants that are not available for purchase.
The importance of environmental tolerances
The major feature of the BPG remains its emphasis on environmental tolerances. Where many other plant databases and texts emphasise the needs of plants, e.g. “needs a moist, well-drained, fertile soil”, at Burnley we recognise that such ideal conditions are rarely to be found. This is especially true of the broader urban landscape but is also true of home gardens where gardeners who wish to minimise their environmental impact understand that modifications such as the importation of soil and/or excessive irrigation are unsustainable in the longer term (and are also expensive). Rather than ask what a plant needs, we ask “what conditions will this plant tolerate, and still perform acceptably?” The BPG helps the user to to ensure plant success by selecting plants for their environmental tolerances, while also taking an environmentally responsible approach to plant selection.
Plant tolerance ratings
Although there has been much research on horticultural and agricultural crops, for the most part, the environmental tolerances of ornamental plants have not been scientifically investigated. In the BPG, plant tolerance ratings are based on evidence such as the natural habitat of the species, or, in the case of some garden cultivars, of parent species. This has been added to by objective observations by horticulturists on the growth and performance of specific plants across a range of environmental conditions. These factors have been combined to develop a rating of specific plant tolerances.
Assessment of plant tolerances
Assessing plant environmental tolerances presents a number of challenges. For example, when rating drought tolerance, it is necessary to recognise that the drought tolerance mechanisms of plants vary: a plant that survives in the desert by tapping deep underground water is in fact avoiding drought, rather than tolerating it, and may perform poorly if grown in a shallow, compacted urban soil.
Often plant tolerance or intolerance of an environmental stress will interact with other prevailing stresses. For example, some plants that require shade in drier sites may be satisfactory in full sun, provided there is enough water in the root zone.
Plant tolerances of drought, salt spray, waterlogged soils and compaction are rated as very good, moderately good, average or poor. Only the most tolerant or intolerant plants are listed as very good or poor respectively. Plants in the BPG are not given a very good tolerance rating if they merely survive an environmental stress.
Brief definitions of the various environmental tolerances (as well as other search criteria) may be found in tool tips on the “advanced search” screen and follow the links for more detailed information.
Soil texture classes
Soil texture classes, such as clay, sand or loam, are less significant for plant growth than the properties of these soils. For example, a plant that has evolved on sand dunes may grow poorly on clay soils, but the problem is more likely to be water-logging caused by the clay’s fine pore structure rather than the clay itself. Such a plant may suffer equally in sandy soils if water is unable to drain away, yet the same plant may succeed on deep, well-drained loams.
For clay soils, plants should be selected for their tolerance to water-logging, while on cracking clays that dry in summer to a hard, impermeable pan, plants that succeed will tolerate both drought and water-logging. On deep, free-draining sands, plants should be selected for drought tolerance.
A number of horticultural and agricultural weeds were included in previous versions of the BPG, as well as a limited number of plants regarded as weeds of remnant bushland, some times called “environmental weeds”. Burnley students are required to learn to recognise and control these, as weed control and management may be a part of their professional practice.
In recent years, increasing awareness of the threat posed to remnant bushland by invasive plants that are often “garden escapes” led us to conclude that a more rigorous approach to the problem of bushland invaders was needed in the BPG. Use of the word “weed” for many of these plants proved problematic, as they are often plants that are still widely grown. In addition, their invasiveness may be a localised problem, specific to certain climatic regions or environmental niches, for example. It was decided to restrict the use of the word “weed” to those plants that are generally recognised as weeds, and are never grown as landscape or garden plants, and to develop a different approach to invasive landscape plants. As well as categorising certain plants as weeds, all the ornamental landscape plants included have been checked for their invasiveness and given an invasiveness rating which will act as a guide to users. Our invasiveness ratings are a simplified version of those given in Groves, R.H. et al 2003, Weed categories for natural and agricultural ecosystem management, Australian Government, Bureau of Rural Sciences, Canberra. For more information on the invasiveness ratings see the tool tips and the links to further information.
It is interesting to note that numerous plants that had been taught as landscape plants when the BPG was in its early years would never be grown now and are confined to the “weed” category. Other plants are still widely grown but are increasingly recognised as invasive and are probably in transition to the weed category; they too may eventually no longer belong in a list of landscape plants.
New in this version is the ability to search on plant traits and on suggested plant uses.
Use the Burnley Plant Guide to search for plants with distinguishing features that you especially value, from bird-attracting to fragrant flowers and aromatic leaves. Architectural form can be selected to find plants that can provide a focal point in a planting, while other traits, including foliage interest, attractive bark, colourful foliage and colourful fruit, can be used to extend a gardenâs, or landscape, period of interest. The category robust, low maintenance includes plants that are tough enough to succeed in hostile sites, such as along roadsides or in many commercial landscapes, where there are minimal resource inputs.
Plants can also have undesirable traits, such as spines, thorns, toxins and allergens. These can also be selected when using the BPG. If a plant is known to be poisonous, this will be indicated under traits in the Other details section of the plant information page; you will find further information under the heading Toxicity in the plant description. While we have done our best to note any plant that has harmful properties, we cannot guarantee that plants that are not indicated as toxic are completely safe.
Plants are often versatile, and obviously can be used in many ways. While some of these categories, such as turf or cut flower are self-explanatory, the following are worthy of a fuller description.
Ground cover can be used for decoration, but perhaps of more importance in many locations is the suppression of weed growth. Plants included as ground cover are those that are capable of forming a dense, weed-suppressing cover. Some plants commonly described as ground covers may be attractive low growing plants but are better regarded as ground decoration.
Shrub mass is a taller form of ground cover using a limited number of species. These plants generally sucker or have a dense massing habit. It is a planting style especially useful in public landscapes.
Plants suitable for hedging have a number of qualities, notably relatively small leaves, multiple basal shoots, the ability to respond readily to regular clipping, and some level of shade tolerance to ensure successful lower growth.
Plants for screening are typically dense, low-branching trees and shrubs that maintain growth to the ground. Climbers can be used but need to be carefully selected to ensure they have the right traits and support structure to develop a screen.
Shading plants are usually trees, or sometimes taller shrubs, that have a canopy that provides effective shade across multiple uses e.g. pedestrians, seating areas and car parks. Trees for shade usually have spreading habits, although more vertical growth can be useful in certain situations.. Shading plants may be evergreen or deciduous. Those with deciduous habits often provide useful light through the cooler months.
Under powerlines covers trees and shrubs that are suitable for planting under power lines, i.e. plants that are unlikely to exceed 6 m in height in typical growing conditions. They will also typically be tolerant of conditions in the streets and roadsides where powerlines are mostly to be found.
Street tree There is no standard recipe for a successful street tree. However the following attributes are of value:
- Tolerance of suboptimal soil conditions
- Tolerance of root disturbance and damage
- "Neat”, regular crown shape - usually globular, ovoid or columnar, although this can depend on the context
- Branching that reduces included bark, co-dominant stems, branch failure
- Straight trunks, or the ability to be trained to a straight trunk
- Low suckering and basal shoot production
- Tolerance of heavy pruning
- Absence of messy fruit and other litter
- Lack of big shallow roots in the zone of rapid taper
- Trees that don't bulge at ground level.*
Ideally, street trees would possess all of these attributes, though in reality few do. When well managed, some less than ideal trees can be successful.
* Thanks to Dr Peter May for these notes on street trees.
Perennial border (sometimes called herbaceous border) is a category that covers the plants used in this garden style. They are typically those plants called in horticulture “herbaceous perennials”, and are usually herbaceous (i.e. non-woody) plants that produce annual flowering or foliage over the spring to autumn period, and become dormant in the winter. In Australia, the term “herbaceous perennial” also includes evergreen perennial herbs such as some Agapanthus species, used widely in borders in our mild climate. Some shrubs and subshrubs can be used in perennial borders too, providing a framework or structure. Gardens that include these woody plants are sometimes referred to as “mixed borders”.
Shrub border Plants in this category typically have showy flowers, but may also be included for their foliage or fragrance. In Australia there is less emphasis on spring to autumn flowering, and many shrubs originating in southern Australia are winter to spring flowering.
Annual display refers to largely herbaceous plants that are used in seasonal bedding displays. They may be annual or biennial herb, but sometimes include short-lived, perennial herbs or subshrubs, such as geraniums, that typically flower profusely or have attractive foliage.
Plants for edging beds and borders are ideally compact, low-growing plants that do not produce vigorous horizontal growth, therefore needing minimum maintenance to keep them from overgrowing lawns, paving and the like. More vigorous plants are often used, but will require more maintenance, and should be chosen with their ultimate size and vigour in mind. Plants that spread by runners or underground rhizomes may be difficult to control.
Plant names and classifications
Taxonomy in the previous edition of the BPG was based on the plant classification system of A. Cronquist (1981). Since then there have been major changes in plant taxonomy at the family level with the work of the Angiosperm Phylogeny Group (APG), a group based at Kew Gardens, England and Missouri Botanic Gardens, USA. The APG is tracing the ancestry of plants, often through their DNA. Acceptance of the APG system is not universal although it appears that most Herbaria in Australia are adopting at least a version of it. In deciding whether or not to adopt the APG system for this version of the BPG, we sought the advice of Dr Neville Walsh of the Melbourne Herbarium. Neville advised us to follow the APG, as he believes it is inevitable that the system will ultimately be universally accepted, even if in a slightly different form from the current version. Thus some users may find this aspect of the BPG unfamiliar. Some plant families have been “lumped” together, swallowing up smaller, familiar families, while some genera have been moved to different families. The changes are too many to list fully here, and interested users are directed to the APG website for further information. Users should also be aware that the APG’s work is still continuing, and further changes can be expected.
Plants are named according to The International Code of Nomenclature for algae, fungi and plants (Melbourne Code) 2011 and the Cultivated Code (International Code of Nomenclature for Cultivated Plants 2009). For Australian plants we have used the Australian Plant Census as our authority where possible although, as it is a work in progress, not all plant names have been resolved. Where not possible, we follow the usage given in the relevant State Herbaria.
Currently accepted names of exotic plants have been a little more difficult to ascertain than those of Australian plants in the past, but the task is becoming easier. Whenever possible we have aligned genus, species and cultivar names with those used by R. Spencer (1995-2005) in The horticultural flora of south-eastern Australia, UNSW Press, Sydney, although there have been numerous changes in nomenclature since the earlier volumes of this series were published. The publicaton of on-line Floras such as the Flora of China and some others has been helpful. For exotic monocots we have relied on the Royal Botanic Gardens Kew Checklist of selected plant families.
Although we have approached contentious family, genus and species attributions conservatively, name changes are inevitable as scientific research reveals more about plant relationships. For this reason, changes in nomenclature such as the renaming of the Australian grass genus Danthonia as Austrodanthonia and, most recently moving it to the genus Rytidosperma, are accepted in the guide.
For those involved in horticulture and landscape professions, a thorough knowledge of plants is fundamental. The first step towards learning what may at first seem an overwhelming number of plants involves a two stage process of learning to recognise the plants, and learning to correctly use (and spell) their scientific (botanical) names.
Human beings, it is said, are able to recognise human faces, in all their variety, from infancy. To many people, however including new students, the world of plants is a green blur, and it is only after many weeks of exposure to a range of plants, and constant “rote learning” of their names, that patterns begin to emerge. Students must learn a certain number of plants for their regular plant recognition tests but, luckily for the lay plants-person, learning can be a more leisurely affair, sometimes occurring over many years.
While it may be possible to recognise a plant (especially true of trees) from a distance, it is also possible to make mistakes that way. To be really certain of a plant’s identity, you must look closely at its identifying characteristics.
Here are some tips* that students, and others, may find useful to aid their (plant) memories:
- Is the plant a conifer, fern, or flowering plant?
- If a fern, observe details of fronds and sori (spore cases, found on the backs of fertile fronds)
- If a conifer, are the leaves needle-like or scale like? Are the cones rounded, with scales that meet at the edges, or ovoid (egg-shaped) with overlapping scales?
- If the plant has flowers, observe their form, colour and fragrance.
- If the plant has fruit, is it a fleshy fruit, or a dry fruit? What colour and shape? Does it split open? How big is it?
You will learn to recognise plants eventually just by their leaves!
- Are the leaves simple, or compound? If you don’t know what these terms mean, check the glossary.
- How are they arranged on the stem?
- What colour are they? Are they a different colour underneath?
- Are there any hairs on the leaves, or waxy coatings?
- Are they fragrant when crushed?
- Are the margins smooth, or lobed or toothed?
* These tips are based on those in a student hand-out Tips for learning plants, compiled by Suzanne Trajstman, Jill Kellow, James Will and Scott Watson.
- For some plants, (especially eucalypts) bark is often a good clue. Observe less obvious features such as stems and buds, too. In winter, when deciduous plants are bare, buds may one of the best clues to a plant’s identification.
- For some plant groups, such as the genus Eucalyptus, or the Grass family Poaceae, the identifying features are unique to that group, and identifying their members is a specialised skill.
Learning plants is a lifelong joy for people who love them. The wonderful thing is that there are so many of them to learn!