PLANT PROTECTION 4

COMMON AND
BOTANICAL
NAMES
Most plants
have one
to several
common
names
All plants
have a genus
and species
Variations from the
normal form of
the species of
horticultural
interest, are
known as
cultivars, also
there may
be hybrids
MARKETING
NAMES AND
OTHER
DIFFICULTIES
KEEP RECORDS
WHAT IS ITS CORRECT NAME?
Plant identification is an important part of diagnosis
Knowing your plants is an essential starting point for diagnosis. Plants may have a
range of botanical (scientific), common and marketing names. Is the plant really what
your client or label says it is?
Common names. One plant may have several common names and the same
common name may be used for different plants. This is confusing. Bindii is a
problem weed in nearly every state/territory of Australia:
– Common names: Bindii, caltrop, cat-head, catshead, common dubbeltjie, goat
head, gokhru, kanti, Malta Cross, puncture vine, yellow vine.
– Botanical name: Tribulus terrestris.
Botanical names. Plants are named according to rules and recommendations in two
books, the International Code of Botanical Nomenclature (ICBN), and the
International Nomenclature of Cultivated Plants (Cultivated Plant Code).
Nomenclature (naming of a plant) is based on the first published description. The
names of plants or groups are based on types, which are mostly dried herbarium
specimens with published descriptions. These have botanical names.
– If possible, know the botanical name, ie genus and species, so you can reliably
receive information from and give advice to the client (Fig 7 opposite).
– Is the name the current botanical name? A plant has only one correct botanical
name which is always in Latin (except for the cultivar). This is the only one that
can be clearly understood internationally and is generally the key to information
about the plant (Lumley & Spencer 1991, Spencer 2002, 2003). When diagnosing
plant problems you should aim to identify the affected plant by its botanical
name, ie genus, species, variety/cultivar, and, if needed, provenance.
– The botanical name of a plant may change when new knowledge has caused
changes in taxonomy, eg DNA studies. Misidentification may occur when
species introduced to cultivation are wrongly named and the name remains
uncorrected for some time, becoming accepted. An Advisory Panel on
Nomenclature and Taxonomy has been set up by the Royal Horticultural Society
(RHS) to help solve such problems. There is a database and associated
publications to serve this need, eg the free RHS Plant Finder.
Is it the correct cultivar or variety? It is even more difficult to keep track of
cultivars with many quickly falling out of favour. The Australian Cultivar
Registration Authority (ACRA) is the source of correct cultivar names and usage.
The cultivar, variety or provenance is often useful as some may be more or less
susceptible to particular pests or diseases. Cultivar names should be placed after the
botanical (Latin) name for the plant, but for a variety of reasons, retail nurseries may
omit the botanical name.
Many horticulturists identify plants by trying to match a plant or plant part to a
picture, but some may be able to use keys to identify plants to family, genus and
species (see also page 179).
What identification is appropriate for your client’s needs? Is the common name
sufficient for the situation? The common name of a plant may be sufficient if it is
distinctive, eg sweetcorn, however, knowledge of the cultivar is often still necessary.
When there is any likelihood of confusion, the botanical name must be included.
Advisors should aspire to using botanical names – even the family is a start.
References are listed on page 196.
The advent of Plant Breeders Rights (PBR) and branding with trade marks has resulted in
a shift in emphasis from botanical and common names to legally protected marketing
names (Fig.7 opposite). ‘Made-up’ trade names lead to all kinds of confusion. In
addition the system has to accommodate aberrations such as:
Synonyms, hybrids and genetically modified plants.
Plants derived from perpetuated juvenile foliage (some conifers), self-sustaining
prostate varieties (some wattles), virus infected plants (Abutilon), clonal selection of
aberrant growth (witches’ brooms), various seed-raised individuals, lines achieved by
repeated self-fertilisation and graft chimeras.
Details of the affected plant’s names together with any information accessed about the
plant must be permanently recorded as part of proof of diagnosis (see pages 62, 72, 105
and 121).
36 Diagnosis - Step 2. Identify affected plant