Australian National Botanic Gardens
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Australian National Botanic Gardens
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Seedlings
Self-sown seedlings are generally to be removed from the Australian National Botanic Gardens (ANBG). Seedlings are potentially hybrids and are of unknown genetic parentage and are considered weeds in this context. These seedlings can be confused with original plantings of accessioned plants leading to loss of the scientific and genetic integrity of the collection. Horticultural staff are required to remove self-sown seedlings. Exceptions to this are listed below:
Clones low in numbers
Seedlings of clones low in numbers may be retained, but are removed if the clone can be propagated vegetatively from an accessioned plant or from seed collected in the wild. If possible the clone will be re-collected from the wild rather than retaining self-sown seedlings.
Naturally occurring
Seedlings of plants that are naturally occurring on Black Mountain are sometimes retained if they are healthy and attractive specimens growing in a suitable position and location. For example, where naturally occurring Eucalyptus spp. form the canopy cover new recruits of these, especially E. mannifera, E. macrorhyncha and E. rossii, are retained where suitable.
Aesthetics
Self-sown seedlings of accessioned plants are occasionally, and usually temporarily, retained for aesthetics. Eventually these plants may be removed to make room for new plantings. For example, in sections affected by the root disease fungus Armillaria, Xerochrysum bracteatum seedlings may be retained to fill in space where other plants have died.
Naturalised
Plants that are naturalised in the ANBG are sometimes retained if they are healthy and attractive specimens growing in a suitable position and location. For example, Eustrephus latifolius is naturally distributed in the Sydney region and is allowed to self seed in sections within the Sydney Basin Area. Naturalised plants are removed and added to the ANBG weeds list if they have a high weed potential as defined by the weed risk assessment procedure tool of the Council of Heads of Australian National Botanic Gardens.
The ANBG policy of retaining some naturalised seedlings is under review as more plants are becoming naturalised.
Horticultural Research
A limited number of unusual seedlings may be retained for horticultural research. They are monitored by horticultural staff and when of a suitable size are assessed by Living Collections Management for their horticultural potential.
Registering seedlings
Self-sown seedlings that are to be retained permanently are registered, given an accession number and become part of the collection.
Accessioned plants
Accessioned plants that are not tagged and can not be tracked back to their original accession number are generally removed as they can no longer be linked with an original or wild collection. Tracking a plant back to its original accession number can be time consuming and may not be warranted if a clone is well represented in the collection.
Suckers
Root suckers outside of original plantings are generally removed. Root suckers may be retained if this suits the theme or nature of the planting.
Responsibility for plant removal
As custodians of plants within their sections, horticultural staff are required to ensure that tags of accessioned plants are not buried or pruned off as this will result in plant removal.
Generally, the Collections Officer decides whether accessioned plants and suckers are to be removed. The decision to remove plants and suckers is based on:
If more than a few accessioned plants in one area need to be removed the Collections Officer will consult Living Collections management.
Horticultural staff are required to remove self-sown seedlings as part of the management of their sections. Seedlings that have been overlooked by horticultural staff are removed or flagged for removal by Plant Records staff. Horticultural staff must consult with the Collections Officer or Plant Records staff if they want to retain any seedlings. All other seedlings should be removed. Plant Records staff liaise with the Collections Officer before removing or flagging seedlings for removal if seedlings are unusual. Plant Records staff liaise with Horticultural staff before removing or flagging for removal seedlings that are of naturally occurring plants.
Jim Croft
A/g
Director 4 Sept 2006
Date of policy revision: April 2006