Eighteen species are included in the NL Variant model (Table 1), but only fourteen represent commercial species regularly occurring in either Newfoundland or Labrador. Species excluded were those that exist outside or on the periphery of the natural range of the species (e.g., sugar maple, oak). Three broad species (Other Softwood, Other Hardwood, and Unknown) were included to allow non-species specific and rare species in inventory data to be accepted by the model. Speckled alder was also included to represent a non-commercial shrub-like tree species.
USDA Plant Codes are the preferred way to store species information for OSM because these codes are available for nearly all species in North America and are the least likely to change. Species can also be loaded and referenced in commands by using the Variant’s short-hand species keys but note that these codes may vary by Variant.
Maximum projectable tree size constraints for DBH and height (HT), and tree annual increment constraints for DBH (DBHI) and height (HTI) are provided in Table 1. Tree size and increment constraints were originally based on the maximum DBH and HT observed in available data; however, this was found to be restrictive in practice. In this version, maximums were increased for most species, sometimes beyond the range of observations, especially for species with few observations. The NL Variant model will cap tree growth if the individual growth models attempt to predict tree growth beyond these observed limits. Fatal errors or warnings are thrown by OSM if tree size exceed these thresholds.
Actual number of species with species-level parameters may be less than 25. In many cases, very rare species were included in this list if occurrence and management importance was notable. Species with missing parameters are assigned surrogate parameters. Workable surrogates are ordered by species growth similarity (most to least) in the table below for each respective species defined. If species parameters are not defined, then the Variant will check to see if parameters can be copied from the next most suitable surrogate until a set of parameters is set; otherwise, an error is thrown. Species with no surrogates listed below are abundant in the Variant Region and will always have species-specific parameters defined by the various growth, mortality models.
Species groups declared by the NL Variant during model initialization can be used in OSM commands (Table 2) to reduce coding. Users can add their own species groups as well (see OSM Species Commands).
Table 1. Species
defined by the Newfoundland and Labrador Variant.
|
USDA Plant Code |
Acadian Variant Key |
Maximum |
Genus |
Species |
Common Name |
Surrogates |
|||
|
DBH cm |
HT m |
DBHI cm/yr |
HTI m/yr |
||||||
|
ABBA |
BF |
75 |
28 |
1.3 |
1.0 |
Abies |
balsamea |
balsam fir |
|
|
LALA |
TL |
100 |
35 |
1.3 |
1.2 |
Larix |
laricina |
tamarack (native) |
LARIX |
|
PIAB |
NS |
100 |
35 |
1.3 |
1.0 |
Picea |
abies |
Norway spruce |
PIGL, PIRU, PIMA |
|
PIGL |
WS |
100 |
35 |
1.3 |
1.0 |
Picea |
glauca |
white spruce |
PIMA, |
|
PIMA |
BS |
75 |
30 |
1.3 |
1.0 |
Picea |
mariana |
black spruce |
|
|
PIRU |
RS |
100 |
35 |
1.3 |
1.0 |
Picea |
rubens |
red spruce |
PIMA |
|
PIBA2 |
JP |
56 |
35 |
1.3 |
1.2 |
Pinus |
banksiana |
jack pine |
PIRE, PIST |
|
PIRE |
RP |
100 |
35 |
1.8 |
1.2 |
Pinus |
resinosa |
red pine |
PIBA2, PIST |
|
PIST |
WP |
150 |
40 |
1.8 |
1.2 |
Pinus |
strobus |
eastern white pine |
|
|
_TE |
OS |
101 |
30 |
1.3 |
1.0 |
Evergreen |
evergreen |
Evergreen tree |
PIMA |
|
ACRU |
RM |
94 |
30 |
1.3 |
1.0 |
Acer |
rubrum |
red maple |
|
|
BEAL2 |
YB |
150 |
30 |
1.3 |
1.0 |
Betula |
alleghaniensis |
yellow birch |
BEPA |
|
BEPA |
WB |
150 |
28 |
1.3 |
1.0 |
Betula |
papyrifera |
paper birch |
|
|
POBA2 |
BP |
150 |
35 |
1.3 |
1.2 |
Populus |
balsamifera |
balsam poplar |
POTR5 |
|
POTR5 |
TA* |
150 |
35 |
1.3 |
1.2 |
Populus |
tremuloides |
quaking aspen |
POPUL |
|
ALNUS |
AL |
25 |
15 |
0.5 |
1.0 |
Alnus |
spp. |
alder spp. |
BEPA |
|
_TB |
OH |
150 |
30 |
1.3 |
1.0 |
Broadleaf |
broadleaf |
Broadleaf tree |
BEPA |
|
_TREE |
XX |
50 |
18 |
1.3 |
1.0 |
Tree |
unknown |
Unknown tree |
ALNUS, BEPA |
*QA in Acadian Variant.
Table 2. Species groups defined by the Newfoundland and Labrador Variant.
|
GROUP |
SPECIES |
|
SpruceSpecies |
PIRU, PIMA, PIGL, PIAB |
|
LarchSpecies |
LALA |
|
PineSpecies |
PIBA2, PIRE, PIST |
|
MapleSpecies |
ACRU |
|
BirchSpecies |
BEAL2, BEPA |
|
PoplarSpecies |
POBA2, POTR5 |