For the majority of the criteria grading standards and measures have been developed and accepted for the usual specifications of trees. However in some instances it may be necessary to specify other details. The following is a list of some of the NPS Conifers other information which might be used. They should be considered to be indicative and not comprehensive.
Origin and Provenance
These terms are of particular importance in the specification of native (indigenous) plants, or plants which are required from a known source of propagation material. Origin is defined as “the place in which indigenous plants are growing or the place from which non-indigenous plants were originally introduced.”
Provenance is defined as “the place in which any plants, whether indigenous or non-indigenous are growing.”
It is inappropriate to specify particular origin/provenance speculatively. A limited number of specialist growers are producing native species and may be listed as sources. Specifications should be developed following discussions with specialists (ecologists and growers) and then contract grown to precise requirements. It is more straightforward to specify the required provenance (indicating the exact source of the young plants or propagation material) if this is significant to the project.
Current British Standards indicate that the ‘country of origin’ is the country where the plant has been growing for the latter half of the most recent growing season. If this is not acceptable then it may be necessary to require information about the provenance of the propagation material (seed, cuttings, budwood, grafts, etc.) in the specification.
The Conifers – Habit section indicates the natural or most typical shapes in which shrubs can be bought. However, there are other shapes of trees and the following gives some examples of the more common types:
Taxus spp. particularly, are trimmed and available in a range of shapes. The following is indicative but please consult specialist nurseries for further details.