Canada's national forest inventory includes many native conifer species. All except the larches are evergreens. Most are in the pine family, except for yews (in the yew family) and junipers, Alaska cedars and thuja cedars (in the cypress family).
Softwood from North American conifers has a variety of commercial uses. The sturdier timber is milled for plywood, wood veneer and construction framing, including structural support beams and studs. Logs can be fashioned into posts, poles and railroad ties. Less sturdy timber is often ground and processed into pulpwood, principally for papermaking. Resins from sap yield wood tar, turpentine or other terpenes. Some resins and other tree products contain dangerous toxins (not generally listed below).
Key
- Provinces and territories (see the Distribution column): AB Alberta, BC British Columbia, MB Manitoba, NB New Brunswick, NL Newfoundland and Labrador, NS Nova Scotia, NT Northwest Territories, NU Nunavut, ON Ontario, PE Prince Edward Island, QC Quebec, SK Saskatchewan, YT Yukon
Conifers
Species and a common name | Notes and commercial uses | Distribution in Canada
provincial tree of: avg height; |
Limits for soil pH, annual precipitation and low temperature | Tolerance to drought (D), fire (F), liming (L) and shade (S) |
Landscapes, bark and cones with foliage |
---|---|---|---|---|---|
Abies amabilis (Pacific silver fir) | Can reach 70 m (230 ft) in height. The timber is lightweight, with low resin content. The species can easily be distinguished from non-fir conifers by the grey, blistery trunk and rigid branches.
Uses: timber; landscaping, pulpwood, veneers, winter holiday decorations. |
BC
none 50 m (165 ft); slow |
pH 3.3–6.0
97–660 cm (38–260 in) |
D: low F: none L: low S: tolerant |
|
Abies balsamea (balsam fir) | A significant source of food and shelter for wildlife. Horizontal blisters in the bark contain aromatic Canada balsam. The lightweight timber is economically important in Canada.
Uses: timber; landscaping, pulpwood, terpenes, veneers, winter holiday decorations. |
All provinces except BC
NB 18 m (60 ft); slow |
pH 4.0–6.0
33–152 cm (13–60 in) |
D: low F: low L: low S: tolerant |
|
Abies grandis (grand fir) | Can reach 70 m (230 ft) in height. The foliage has a distinct orange-like scent. The wood is soft, and not as durable as in other fir species.
Uses: timber; landscaping, pulpwood, veneers, winter holiday decorations. |
BC
none 46 m (150 ft); moderate |
pH 4.5–7.5
28–254 cm (11–100 in) |
D: medium F: high L: low S: tolerant |
|
Abies lasiocarpa (subalpine fir) | Provides habitat for wildlife and nutrition for livestock. Canada's inventory includes Abies bifolia, now considered a synonym of the variety A. lasiocarpa var. lasiocarpa.
Uses: timber; landscaping, pulpwood, winter holiday decorations. |
AB BC NT YT
YT 27 m (90 ft); slow |
pH 4.0–6.5
51–381 cm (20–150 in) |
D: low F: low L: low S: tolerant |
|
Callitropsis nootkatensis (Alaska cedar) | Formerly a significant timber tree providing durable, multi-use wood. Most of the trees have already been cleared, aside from limited numbers in protected areas. It is listed as Chamaecyparis nootkatensis in Canada's inventory.
Uses: timber; landscaping. |
BC
none 23 m (75 ft); slow |
pH 5.5–7.0
110–250 cm (45–100 in) |
D: low F: low L: none S: tolerant |
|
Juniperus scopulorum (Rocky Mountain juniper) | Usually a shrub or small tree. The wood is durable, especially when seasoned, and suitable for furniture. The resins are aromatic.
Uses: landscaping, posts, veneers. |
AB BC SK
none 15 m (50 ft); slow |
pH 5.0–8.5
23–66 cm (9–26 in) |
D: high F: low L: high S: intolerant |
|
Juniperus virginiana (eastern red cedar) | An important support species for wildlife throughout its range. Although the tree has limited commercial use, the wood is highly valued for its appearance and robustness. The resins are aromatic.
Uses: landscaping, posts, veneers, winter holiday decorations. |
ON QC
none 15 m (50 ft); slow |
pH 4.7–8.0
38–173 cm (15–68 in) |
D: high F: low L: high S: medium |
|
Larix laricina (tamarack) | Adapted to a variety of poor soil conditions, including peatland. The tree has one of the widest distributions among North American conifers.
Uses: timber; landscaping, posts, pulpwood. |
All provinces and territories
NT 24 m (80 ft); rapid |
pH 5.5–6.5
18–140 cm (7–55 in) |
D: low F: none L: low S: intolerant |
|
Larix lyallii (subalpine larch) | Distinguishable from western larch by its woolly buds and new growth. In its range, the subalpine larch is often found growing higher on cold mountain slopes than other trees.
Uses: landscaping. |
AB BC
none 12 m (40 ft); slow |
pH 3.9–5.6
66–241 cm (26–95 in) |
D: high F: low L: none S: intolerant |
|
Larix occidentalis (western larch) | The largest larch, and the most important one commercially for its timber. Also a significant source of arabinogalactan, a gum used as a thickening agent.
Uses: timber; landscaping, posts, pulpwood, veneers. |
AB BC
none 61 m (200 ft); rapid |
pH 6.0–7.0
33–127 cm (13–50 in) |
D: low F: low L: low S: intolerant |
|
Picea engelmannii (Engelmann spruce) | Typically contains many small wood knots that lower the grade of the timber. The light colour, long fibres and very low resin content contribute to the quality of its pulpwood.
Uses: timber; landscaping, posts, pulpwood, terpenes, veneers. |
AB BC
none 37 m (120 ft); slow |
pH 6.0–8.0
53–406 cm (21–160 in) |
D: low F: low L: high S: tolerant |
|
Picea glauca (white spruce) | One of the main sources of Canadian pulpwood and construction timber. It is also used to build furniture, pallets and musical instruments.
Uses: timber; pulpwood. |
All provinces and territories
MB 30 m (100 ft); slow |
pH 4.0–8.2
18–127 cm (7–50 in) |
D: high F: low L: low S: medium |
|
Picea mariana (black spruce) |
Mainly harvested for pulpwood; construction uses are limited by the small size (for a spruce). The pale yellow wood is lightweight but strong. Birds commonly seen in groves in summer months include ruby-crowned kinglets, ovenbirds and Setophaga warblers. Uses: timber; landscaping, pulpwood, terpenes, winter holiday decorations. |
All provinces and territories
NL 20 m (65 ft); slow |
pH 4.7–6.5
13–152 cm (5–60 in) |
D: low F: none L: low S: tolerant |
|
Picea rubens (red spruce) | The straight-grained wood is lightweight but strong. It is the most popular choice in many stringed instruments for its resonance.
Uses: timber; posts, pulpwood, terpenes, veneers. |
All eastern provinces
NS 34 m (110 ft); moderate |
pH 4.0–5.8
71–132 cm (28–52 in) |
D: medium F: none L: low S: tolerant |
|
Picea sitchensis (Sitka spruce) | The largest spruce, and one of the most prominent along the western Canadian coastline. The strong wood is used in light aircraft, masts and turbine blades. It is also used in many musical instruments for its resonance.
Uses: timber; pulpwood, terpenes. |
BC
none 61 m (200 ft); moderate |
pH 3.9–5.7
56–572 cm (22–225 in) |
D: low F: none L: medium S: tolerant |
|
Pinus albicaulis (whitebark pine) | A slow-growing and long-lived pioneer species that helps reduce the movement of soil and snow. The seeds are a source of nutrition for birds, small mammals, black bears and grizzly bears.
Uses: no significant economic uses. |
AB BC
none 20 m (65 ft); slow |
pH 4.8–8.0
46–183 cm (18–72 in) |
D: high F: none L: low S: medium |
|
Pinus banksiana (jack pine) | Sometimes milled for utility poles and railroad ties. It has the broadest distribution of any pine species in the country.
Uses: timber; landscaping, posts, pulpwood, terpenes. |
All except YT, NU
none 24 m (80 ft); rapid |
pH 6.0–8.2
38–89 cm (15–35 in) |
D: low F: none L: low S: intolerant |
|
Pinus contorta (lodgepole pine) | Used in paneling, and sometimes milled for utility poles and railroad ties. The trees usually grow rapidly when young and can be harvested economically. Canada's inventory includes the varieties P. contorta var. contorta and P. contorta var. latifolia.
Uses: timber; posts, pulpwood, terpenes, veneers. |
AB BC NT SK YT
AB 30 m (99 ft); rapid |
pH 6.2–7.5
46–64 cm (18–25 in) |
D: low F: low L: high S: intolerant |
|
Pinus flexilis (limber pine) | A slow-growing species not usually planted for its timber, but sometimes harvested along with other species. It is adapted to harsh climates, including windy and dry conditions, and provides the only tree cover available on some sites. The species is long-lived; one specimen was found to be 1650 years old.
Uses: timber; landscaping, edible seeds |
AB BC
none 20 m (66 ft); slow |
pH 5.7–6.5
51–178 cm (20–70 in) |
D: high F: low L: medium S: intolerant |
|
Pinus monticola (Western white pine) | Straight-grained, lightweight and low in resin, the timber is often used in framing and woodworking.
Uses: timber; landscaping, pulpwood, terpenes, veneers. |
AB BC
none 61 m (200 ft); rapid |
pH 5.5–7.0
38–76 cm (15–30 in) |
D: low F: low L: medium S: medium |
|
Pinus ponderosa (ponderosa pine) | Can reach more than 230 ft (70 m) in height. It is a widely distributed tree in western North America, and one of the main sources of timber, with a relatively fast growth rate.
Uses: timber; landscaping, posts, pulpwood, terpenes, veneers. |
BC
none 68 m (223 ft); moderate |
pH 5.0–9.0
38–64 cm (15–25 in) |
D: high F: high L: low S: intolerant |
|
Pinus resinosa (red pine) | One of the fastest-growing and most frequently planted conifer species in Canada. The wood is straight-grained and moderately hard. Some of it is milled for railroad ties and cabin logs.
Uses: timber; landscaping, posts, pulpwood, veneers, winter holiday decorations. |
All eastern provinces + MB
none 24 m (80 ft); rapid |
pH 4.5–6.0
38–152 cm (15–60 in) |
D: low F: low L: none S: intolerant |
|
Pinus rigida (pitch pine) | Rigida (rigid) refers to the needles and cone scales. The wood, resinous and rot-resistant, is suitable for shipbuilding, mine timbers, fencing and railroad ties.
Uses: landscaping, posts, pulpwood, terpenes, winter holiday decorations. |
NS ON QC
none 24 m (80 ft); rapid |
pH 3.5–5.1
94–142 cm (37–56 in) |
D: medium F: low L: low S: intolerant |
|
Pinus strobus (eastern white pine) | One of the most commercially important trees in eastern North America, in part due to its rapid growth. The timber is durable but soft enough for woodworking.
Uses: timber; landscaping, posts, pulpwood, veneers, winter holiday decorations. |
All eastern provinces + MB
ON 46 m (150 ft); rapid |
pH 4.0–6.5
51–203 cm (20–80 in) |
D: none F: none L: none S: medium |
|
Pseudotsuga menziesii (Douglas fir) | Worldwide, one of the most commercially successful timber trees. Canada's inventory includes the varieties P. menziesii var. glauca and P. menziesii var. menziesii.
Uses: timber; landscaping, posts, pulpwood, terpenes, veneers, winter holiday decorations. |
AB BC
none 61 m (200 ft); moderate |
pH 5.0–7.5
46–254 cm (18–100 in) |
D: low F: low L: low S: medium |
|
Taxus brevifolia (western yew) | A shade-tolerant tree of the Yew family. When competing with taller and faster-growing trees, it becomes part of the undergrowth. The seed cones have red arils.
Uses: landscaping, posts. |
AB BC
none 12 m (40 ft); slow |
pH 6.2–7.5
61–152 cm (24–60 in) |
D: medium F: low L: low S: tolerant |
|
Thuja occidentalis (eastern white-cedar) | The termite- and rot-resistant wood, durable in a range of outdoor conditions, is used in fencing, cabin logs and roof shingles.
Uses: timber; landscaping, posts, pulpwood, veneers. |
MB and all eastern provinces except NL
none 15 m (50 ft); slow |
pH 5.2–7.0
89–140 cm (35–55 in) |
D: low F: low L: high S: medium |
|
Thuja plicata (western redcedar) | The only native Thuja species in western North America. The lightweight, durable wood makes good insulation, and is often used in shingles and other roofing materials.
Uses: timber; landscaping, posts, pulpwood, veneers. |
AB BC
BC 46 m (150 ft); slow |
pH 5.1–7.1
76–305 cm (30–120 in) |
D: low F: low L: medium S: tolerant |
|
Tsuga canadensis (eastern hemlock) | Shade-tolerant, long-lived and slow-growing. Historically, it provided tannin for curing leather.
Uses: timber; landscaping, pulpwood. |
All eastern provinces except NL
none 32 m (105 ft); slow |
pH 4.2–5.7
81–140 cm (32–55 in) |
D: low F: medium L: none S: tolerant |
|
Tsuga heterophylla (western hemlock) | Used widely in construction. It is also a good source of wood fibre.
Uses: timber; landscaping, pulpwood, veneers. |
AB BC
none 52 m (170 ft); slow |
pH 4.5–6.0
97–381 cm (38–150 in) |
D: low F: low L: none S: tolerant |
|
Tsuga mertensiana (mountain hemlock) | Grows well in snow-covered subalpine zones.
Uses: timber; landscaping, pulpwood, veneers. |
BC
none 38 m (125 ft); slow |
pH 4.5–7.3
110–360 cm (42–140 in) |
D: low F: low L: low S: tolerant |
Genera
Genus, a common name, and family (if not the pine family) | Low-oxygen soil tolerance | Cold winters needed |
Frost-free days needed |
Moisture use | Soil salinity tolerance |
---|---|---|---|---|---|
Abies (firs) | None (low for A. grandis) | Yes | 60–120 | Medium | None |
Callitropsis (Alaska cedar, cypress family) | Low | Yes | 111 | Medium | None |
Juniperus (junipers, cypress family) | Low or none | Yes | 120–140 | Low | Low |
Larix (larches) | None (low for L. laricina) | Yes (no for L. lyallii) | 60–90 | Low (medium for L. laricina) | None (low for L. laricina) |
Picea (spruces) | Low or none | No (yes for P. glauca and P. mariana) |
30–111 | Medium (high for P. mariana) | None (medium for P. glauca) |
Pinus (pines) | Low or none | Yes | 50–150 | Medium or low | Low or none (medium for P. ponderosa) |
Pseudotsuga (Douglas firs) | Low | Yes | 130 | Medium | Low |
Taxus (yews, yew family) | None | Yes | 140 | Low | None |
Thuja (thuja cedars, cypress family) | Medium (none for T. plicata) | Yes | 100–180 | Medium | Medium (none for T. plicata) |
Tsuga (hemlocks) | None | Yes | 80–160 | Medium (high for T. mertensiana) | None |
See also
- List of gymnosperm families
- List of inventoried conifers in the United States
- List of inventoried hardwoods in the United States
Notes
- This list omits hybrids and varieties. The taxonomy (classification) comes from Plants of the World Online except as noted.
- Thuja cedars are often called just cedars, but so are many other species.
- Of these sources, only Plants of the World Online lists this as Picea laxa.
- For further explanations of the columns, see the Help Document at "Growth Requirements".
Citations
- ^ CNFI, Tree Species List.
- ^ POWO.
- National Plant Data Team 2023, Characteristics, Leaf Retention.
- ^ National Plant Data Team & Stevens 2023, Thuja occidentalis: Plant Guide; Characteristics.
- ^ Johnston 1991, pp. 580, 587.
- POWO, Taxus, Juniperus, Callitropsis, Thuja.
- National Plant Data Team 2023, Help Document.
- ^ National Plant Data Team 2023.
- Canadian Heritage 2017.
- ^ National Plant Data Team & Wilken 2023, Abies amabilis: Plant Guide; Characteristics.
- Crawford & Oliver 1991, pp. 22, 23.
- ^ National Plant Data Team & Northeast Plant Materials Program 2023, Abies balsamea: Fact Sheet; Characteristics.
- Frank 1991, pp. 26–34.
- ^ National Plant Data Team & Nesom 2023, Abies grandis: Plant Guide; Characteristics.
- Foiles, Graham & Olson 1991, pp. 52–58.
- ^ CNFI.
- POWO, Abies bifolia.
- ^ National Plant Data Team & Nesom 2023, Abies lasiocarpa: Plant Guide; Characteristics.
- Alexander, Shearer & Shepperd 1991, pp. 60–68.
- ^ National Plant Data Team 2023, Callitropsis nootkatensis: Characteristics.
- ^ Harris 1991, pp. 97–102.
- POWO, Chamaecyparis.
- ^ National Plant Data Team & Stevens 2023, Juniperus scopulorum: Plant Guide; Characteristics.
- Noble 1991, pp. 116–126.
- ^ National Plant Data Team et al. 2023, Juniperus virginiana: Plant Guide; Characteristics.
- Lawson 1991, pp. 131–140.
- ^ National Plant Data Team & Nesom 2023, Larix laricina: Plant Guide; Characteristics.
- Johnston 1991, pp. 141–151.
- ^ National Plant Data Team 2023, Larix lyallii: Characteristics.
- Arno 1991, pp. 152–159.
- ^ National Plant Data Team 2023, Larix occidentalis: Characteristics.
- Schmidt & Shearer 1991, pp. 160–172.
- ^ National Plant Data Team & Nesom 2023, Picea engelmannii: Plant Guide; Characteristics.
- Alexander & Shepperd 1991, pp. 187–203.
- ^ National Plant Data Team & Nesom 2023, Picea glauca: Plant Guide; Characteristics.
- POWO, Picea glauca.
- Nienstaedt & Zasada 1991, pp. 204–226.
- ^ National Plant Data Team & Nesom 2023, Picea mariana: Plant Guide; Characteristics.
- Viereck & Johnston 1991, pp. 227–237.
- ^ National Plant Data Team & Plant Materials Program 2023, Picea rubens: Fact Sheet; Characteristics.
- Blum 1991, pp. 250–259.
- ^ National Plant Data Team & Moore 2023, Picea sitchensis: Plant Guide; Characteristics.
- Harris 1991, pp. 260–267.
- ^ National Plant Data Team et al. 2023, Pinus albicaulis: Plant Guide; Characteristics.
- Arno & Hoff 1991, pp. 268–279.
- ^ National Plant Data Team, Moore & Wilson 2023, Pinus banksiana: Plant Guide; Characteristics.
- Rudolph & Laidly 1991, pp. 280–293.
- ^ National Plant Data Team 2023, Pinus contorta: Characteristics.
- Lotan & Critchfield 1991, pp. 302–315.
- ^ National Plant Data Team 2023, Pinus flexilis: Characteristics.
- Steele 1991, pp. 348–354.
- ^ National Plant Data Team 2023, Pinus monticola: Characteristics.
- Graham 1991, pp. 385–394.
- ^ National Plant Data Team & Wennerberg 2023, Pinus ponderosa: Plant Guide; Characteristics.
- Oliver & Ryker 1991, pp. 413–424.
- ^ National Plant Data Team & Moore 2023, Pinus resinosa: Plant Guide; Characteristics.
- Rudolf 1991, pp. 442–455.
- ^ National Plant Data Team 2023, Pinus rigida: Characteristics.
- Little & Garrett 1991, pp. 456–462.
- ^ National Plant Data Team & Dickerson 2023, Pinus strobus: Fact Sheet; Characteristics.
- Wendel & Smith 1991, pp. 476–488.
- ^ National Plant Data Team & Stevens 2023, Pseudotsuga menziesii: Characteristics.
- Hermann & Lavender 1991, pp. 527, 537.
- ^ National Plant Data Team & Stevens 2023, Taxus brevifolia: Characteristics.
- Bolsinger & Jaramillo 1991, pp. 573, 577, 578.
- ^ National Plant Data Team & Stevens 2023, Thuja plicata: Plant Guide; Characteristics.
- Minore 1991, pp. 590, 598.
- ^ National Plant Data Team & Stevens 2023, Tsuga canadensis: Plant Guide; Characteristics.
- Godman & Lancaster 1991, pp. 604, 611.
- ^ National Plant Data Team & Stevens 2023, Thuja heterophylla: Plant Guide; Characteristics.
- Packee 1991, pp. 613, 621.
- ^ National Plant Data Team & Stevens 2023, Tsuga mertensiana: Plant Guide; Characteristics.
- Means 1991, pp. 623, 630.
- National Plant Data Team 2023, Help Document.
References
All growth requirements from the USDA Plants Database were last retrieved on March 17, 2024.- Alexander, Robert R.; Shearer, Raymond C.; Shepperd, Wayne D. (1991). "Abies lasiocarpa". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 60–68. ISBN 978-0-16-029260-6.
- Alexander, Robert R.; Shepperd, Wayne D. (1991). "Picea engelmannii". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 187–203. ISBN 978-0-16-029260-6.
- Arno, Stephen F. (1991). "Larix lyallii". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 152–159. ISBN 978-0-16-029260-6.
- Arno, Stephen F.; Hoff, Raymond J. (1991). "Pinus albicaulis". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 268–279. ISBN 978-0-16-029260-6.
- Blum, Barton M. (1991). "Picea rubens". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 250–259. ISBN 978-0-16-029260-6.
- Bolsinger, Charles L.; Jaramillo, Annabelle E. (1991). "Taxus brevifolia". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 573–578. ISBN 978-0-16-029260-6.
- Canadian Heritage (2017). "Provincial and territorial symbols". Ottawa, Ontario: Government of Canada. Retrieved April 19, 2024.
- CNFI (2014). "Canada's National Forest Inventory". Ottawa, Ontario: Government of Canada. Retrieved October 15, 2023.
- Crawford, Peggy D.; Oliver, Chadwick Dearing (1991). "Abies amabilis". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 17–23. ISBN 978-0-16-029260-6.
- Foiles, Marvin W.; Graham, Russel T.; Olson, David F. Jr. (1991). "Abies grandis". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 52–58. ISBN 978-0-16-029260-6.
- Frank, Robert M. (1991). "Abies balsamea". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 26–34. ISBN 978-0-16-029260-6.
- Godman, R. M.; Lancaster, Kenneth (1991). "Tsuga canadensis". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 604–611. ISBN 978-0-16-029260-6.
- Graham, Russell T. (1991). "Pinus monticola". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 385–394. ISBN 978-0-16-029260-6.
- Harris, A. S. (1991). "Callitropsis nootkatensis; Picea sitchensis". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 97–102, 260–267. ISBN 978-0-16-029260-6.
- Hermann, Richard K.; Lavender, Denis P. (1991). "Pseudotsuga menziesii". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 527–537. ISBN 978-0-16-029260-6.
- Johnston, William F. (1991). "Larix laricina; Thuja occidentalis". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 141–151, 580–587. ISBN 978-0-16-029260-6.
- Lawson, Edwin R. (1991). "Juniperus virginiana". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 131–140. ISBN 978-0-16-029260-6.
- Little, Silas; Garrett, Peter W. (1991). "Pinus rigida". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 456–462. ISBN 978-0-16-029260-6.
- Lotan, James E.; Critchfield, William B. (1991). "Pinus contorta". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 302–315. ISBN 978-0-16-029260-6.
- Means, Joseph E. (1991). "Tsuga mertensiana". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 623–630. ISBN 978-0-16-029260-6.
- Minore, Don (1991). "Thuja plicata". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 590–598. ISBN 978-0-16-029260-6.
- National Plant Data Team (2023). "Citing the PLANTS Database". USDA Plants Database. Washington, DC, US: Natural Resources Conservation Service, US Department of Agriculture. Retrieved October 16, 2023.
- National Plant Data Team; Dickerson, John (2023). "Pinus strobus". USDA Plants Database. Washington, DC, US: Natural Resources Conservation Service, US Department of Agriculture. Retrieved October 16, 2023.
- National Plant Data Team; Moore, Lincoln M. (2023). "Picea sitchensis; Pinus resinosa". USDA Plants Database. Washington, DC, US: Natural Resources Conservation Service, US Department of Agriculture. Retrieved October 16, 2023.
- National Plant Data Team; Moore, Lincoln M.; Wilson, Jeffrey D. Walker (2023). "Pinus banksiana". USDA Plants Database. Washington, DC, US: Natural Resources Conservation Service, US Department of Agriculture. Retrieved October 16, 2023.
- National Plant Data Team; Nesom, Guy (2023). "Abies grandis, Abies lasiocarpa, Larix laricina, Picea engelmannii, Picea glauca; Picea mariana". USDA Plants Database. Washington, DC, US: Natural Resources Conservation Service, US Department of Agriculture. Retrieved October 16, 2023.
- National Plant Data Team; Northeast Plant Materials Program (2023). "Abies balsamea". USDA Plants Database. Washington, DC, US: Natural Resources Conservation Service, US Department of Agriculture. Retrieved October 16, 2023.
- National Plant Data Team; Plant Materials Program (2023). "Picea rubens". USDA Plants Database. Washington, DC, US: Natural Resources Conservation Service, US Department of Agriculture. Retrieved October 16, 2023.
- National Plant Data Team; Stevens, Michelle (2023). "Juniperus scopulorum". USDA Plants Database. Washington, DC, US: Natural Resources Conservation Service, US Department of Agriculture. Retrieved October 16, 2023.
- National Plant Data Team; Stevens, Michelle; Kaiser, Jerry; Dozier, Ivan (2023). "Juniperus virginiana". USDA Plants Database. Washington, DC, US: Natural Resources Conservation Service, US Department of Agriculture. Retrieved October 16, 2023.
- National Plant Data Team; Tilley, Derek; St. John, Loren; Ogle, Dan (2023). "Pinus albicaulis". USDA Plants Database. Washington, DC, US: Natural Resources Conservation Service, US Department of Agriculture. Retrieved October 16, 2023.
- National Plant Data Team; Wennerberg, Sarah (2023). "Pinus ponderosa". USDA Plants Database. Washington, DC, US: Natural Resources Conservation Service, US Department of Agriculture. Retrieved October 16, 2023.
- National Plant Data Team; Wilken, Dieter (2023). "Abies amabilis". USDA Plants Database. Washington, DC, US: Natural Resources Conservation Service, US Department of Agriculture. Retrieved October 16, 2023.
- Nienstaedt, Hans; Zasada, John C. (1991). "Picea glauca". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 204–226. ISBN 978-0-16-029260-6.
- Noble, Daniel L. (1991). "Juniperus scopulorum". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 116–126. ISBN 978-0-16-029260-6.
- Oliver, William W.; Ryker, Russell A. (1991). "Pinus ponderosa". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 413–424. ISBN 978-0-16-029260-6.
- Packee, E. C. (1991). "Tsuga heterophylla". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 613–621. ISBN 978-0-16-029260-6.
- POWO (2019). "Plants of the World Online". London: Royal Botanic Gardens, Kew. Retrieved January 10, 2023. See their terms-of-use license.
- Rudolf, Paul O. (1991). "Pinus resinosa". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 442–455. ISBN 978-0-16-029260-6.
- Rudolph, T. D.; Laidly, P. R. (1991). "Pinus banksiana". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 280–293. ISBN 978-0-16-029260-6.
- Schmidt, Wyman C.; Shearer, Raymond C. (1991). "Larix occidentalis". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 160–172. ISBN 978-0-16-029260-6.
- Steele, Robert (1991). "Pinus flexilis". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 348–354. ISBN 978-0-16-029260-6.
- Viereck, Leslie A.; Johnston, William F. (1991). "Picea mariana". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 227–237. ISBN 978-0-16-029260-6.
- Wendel, G. W.; Smith, H. Clay (1991). "Pinus strobus". In Burns, Russell M.; Honkala, Barbara H. (eds.). Silvics of North America, Volume 1. Conifers. Washington, DC: US Forest Service, Department of Agriculture (US Government Printing Office). pp. 476–488. ISBN 978-0-16-029260-6.