
Tsuga canadensis
Tsuga canadensis
Safety & Hazards
None known
Cultivation Details
Tsuga canadensis grows in the cool, humid temperate zone of eastern N. America where the mean annual precipitation is around 700 - 1,500mm[1]. An easily grown plant, it thrives best when growing in a deep well-drained soil in the more humid regions of the temperate zone, where it appreciates the higher rainfall[2]. However, it succeeds in most soils and positions, being especially good on acidic sandy soils[3] but also tolerating some lime[2] so long as there is plenty of humus in the soil[4]. In the wild plants are often found on highly acidic soils with a pH in the range 3 - 4[1]. Plants are very shade tolerant when young, but need more sunlight as they grow older[3, 5]. Plants are thin and poor when grown in dry or exposed places[5]. Seedlings grow slowly and cannot tolerate full sunlight until fully established, usually when they are 90 - 150cm tall[6]. Tsuga canadensis is the most shade tolerant of all tree species and saplings may remain in the understory in natural stands for 25 - 400 years waiting for a gap to appear in the canopy and can then grow relatively quickly to exploit that gap[7]. A slow-growing but long-lived species in the wild, with specimens nearly 1,000 years old recorded[8]. It is very slow growing in cultivation for the first few years, it then grows more rapidly with annual shoots up to 60cm long. This rate of growth soon slows as the tree loses apical dominance and it becomes slow growing again[9]. The tree has shallow, wide-spreading roots and casts a dense shade. Especially when growing in stands, it allows very little other plant life to flourish beneath it[1]. The shallow root system makes trees highly susceptible to wind-throw when exposed through timber cutting or planted in open sites. Plants should be staked for the first two or three years following transplant in order to prevent wind-throw[7]. Saplings and small trees are highly susceptible to damage from fire because of the thin bark, and root injury often also occurs from high intensity fires because of heavy litter concentration[7]. Seed production commences around the age of 20 - 40 years, with good crops produced every 3 - 4 years[8]. The crushed foliage has a sweet lemony scent[9]. Another report says that it emits the unpleasant smell of hemlock[10]. An insect pest introduced to N. America, the Hemlock Woolly Adelgid (Adelges tsugae) is causing substantial dieback in many areas, expanding from Virginia where it was apparently introduced in 1951 to the north and east. It has not yet reached the main area of occupancy around the Great Lakes. Moderating temperatures associated with climate change could allow the spread of this pest into areas where it has so far been prevented from infesting due to low winter temperatures[1]. Many named forms have been selected for their ornamental value[9]. Almost all of them are dwarf forms[5]. Tsuga canadensis is the state tree of Pennsylvania[11]. Plants in this genus are notably resistant to honey fungus[5].
Propagation
Seed - it germinates better if given a short cold stratification[12, 13] and so is best sown in a cold frame in autumn to late winter. It can also be sown in early spring, though it might not germinate until after the next winter. If there is sufficient seed, an outdoor sowing can be made in spring[14]. Pot-grown seedlings are best potted up into individual pots once they are large enough to handle - grow them on in a cold frame and plant them out in early summer of the following year. Trees transplant well when they are up to 80cm tall, but they are best put in their final positions when they are about 30 - 45 cm or less tall, this is usually when they are about 5 - 8 years old[5]. Larger trees will check badly and hardly put on any growth for several years. This also badly affects root development and wind resistance[5]. Cite as: Temperate Plants Database, Ken Fern. temperate.theferns.info. 2026-02-21. <temperate.theferns.info/plant/Tsuga+canadensis>
Pollinators
Wind
References
- [1]IUCN Red List of Threatened Species — http://www.iucnredlist.org/ ↩︎A list of plants under threat and facing possible extinction, usually with brief details of the threats and information on habitat.
- [2]Trees and Shrubs Hardy in Great Britain. Vol 1 - 4 and Supplement. — Bean. W. · Murray · 1981 · ISBN - ↩︎A classic with a wealth of information on the plants, but poor on pictures.
- [3]Conifers. — Rushforth. K. · Christopher Helm · 1987 · ISBN 0-7470-2801-X ↩︎Deals with conifers that can be grown outdoors in Britain. Good notes on cultivation and a few bits about plant uses.
- [4]Plants for Ground Cover — Thomas. G. S. · J. M. Dent & Sons · 1990 · ISBN 0-460-12609-1 ↩︎An excellent detailled book on the subject, very comprehensive.
- [5]The New RHS Dictionary of Gardening. 1992. — Huxley. A. · MacMillan Press · 1992 · ISBN 0-333-47494-5 ↩︎Excellent and very comprehensive, though it contains a number of silly mistakes. Readable yet also very detailed.
- [6]Fire Effects Information System — http://www.feis-crs.org/feis/ ↩︎An on-line information site with comprehensive information on over 1,100 species of plant. Mainly developed to supply information on the effects of fire on plants and animals, it also contains a wealth of other information on the plants
- [7]Plants Database — United States Department of Agriculture · http://plants.usda.gov/java/factSheet ↩︎An online database with an excellent collection of fact sheets about native N. American plants.
- [8]The Complete Trees of N. America. Field Guide and Natural History. — Elias. T. · Van Nostrand Reinhold Co. · 1980 · ISBN 0442238622 ↩︎A very good concise guide. Gives habitats, good descriptions, maps showing distribution and a few of the uses. It also includes the many shrubs that occasionally reach tree proportions.
- [9]Conifers in the British Isles. — Mitchell. A. F. · HMSO · 1975 · ISBN 0-11-710012-9 ↩︎A bit out of date (first published in 1972), but an excellent guide to how well the various species of conifers grow in Britain giving locations of trees.
- [10]Scented Flora of the World. — Genders. R. · Robert Hale. London. · 1994 · ISBN 0-7090-5440-8 ↩︎An excellent, comprehensive book on scented plants giving a few other plant uses and brief cultivation details. There are no illustrations.
- [11]Flora of N. America — http://flora.huh.harvard.edu/fna/ ↩︎An on-line version of the flora with an excellent description of the plant including a brief mention of plant uses.
- [12]Hardy Woody Plants from Seed. — McMillan-Browse. P. · Grower Books · 1985 · ISBN 0-901361-21-6 ↩︎Does not deal with many species but it is very comprehensive on those that it does cover. Not for casual reading.
- [13]The Reference Manual of Woody Plant Propagation. — Dirr. M. A. and Heuser. M. W. · Athens Ga. Varsity Press · 1987 · ISBN 0942375009 ↩︎A very detailed book on propagating trees. Not for the casual reader.
- [14]Propagation of Trees, Shrubs and Conifers. — Sheat. W. G. · MacMillan and Co · 1948 · ISBN - ↩︎A bit dated but a good book on propagation techniques with specific details for a wide range of plants.
- [15]Flora Europaea — ? · Cambridge University Press · 1964 · ISBN - ↩︎An immense work in 6 volumes (including the index). The standard reference flora for Europe, it is very terse though and with very little extra information. Not for the casual reader.
- [16]The Herb Book. — Lust. J. · Bantam books · 1983 · ISBN 0-553-23827-2 ↩︎Lots of information tightly crammed into a fairly small book.
- [17]Manual of the Trees of N. America. — Sargent. C. S. · Dover Publications Inc. New York. · 1965 · http://www.biodiversitylibrary.org/ · ISBN 0-486-20278-X ↩︎Two volumes, a comprehensive listing of N. American trees though a bit out of date now. Good details on habitats, some details on plant uses. Not really for the casual reader. It can be downloaded from the internet.
- [18]Earth Medicine, Earth Food. — Weiner. M. A. · Ballantine Books · 1980 · ISBN 0-449-90589-6 ↩︎A nice book to read though it is difficult to look up individual plants since the book is divided into separate sections dealing with the different medicinal uses plus a section on edible plants. Common names are used instead of botanical.
- [19]Sturtevant's Edible Plants of the World. — Hedrick. U. P. · Dover Publications · 1972 · ISBN 0-486-20459-6 ↩︎Lots of entries, quite a lot of information in most entries and references.
- [20]Dictionary of Economic Plants. — Uphof. J. C. Th. · Weinheim · 1959 · ISBN - ↩︎An excellent and very comprehensive guide but it only gives very short descriptions of the uses without any details of how to utilize the plants. Not for the casual reader.
- [21]Food Plants of the N. American Indians. — Yanovsky. E. · U.S. Depf of Agriculture. · ISBN - ↩︎A comprehensive but very terse guide. Not for the casual reader.
- [22]Cornucopia - A Source Book of Edible Plants. — Facciola. S. · Kampong Publications · 1990 · ISBN 0-9628087-0-9 ↩︎Excellent. Contains a very wide range of conventional and unconventional food plants (including tropical) and where they can be obtained (mainly N. American nurseries but also research institutes and a lot of other nurseries from around the world.
- [23]A Field Guide to N. American Edible Wild Plants. — Elias. T. and Dykeman. P. · Van Nostrand Reinhold · 1982 · ISBN 0442222009 ↩︎Very readable.
- [24]Edible and Useful Wild Plants of the United States and Canada. — Saunders. C. F. · Dover Publications · 1976 · ISBN 0-486-23310-3 ↩︎Useful wild plants of America. A pocket guide.
- [25]Wild Food Plants of Indiana. — McPherson. A. and S. · Indiana University Press · 1977 · ISBN 0-253-28925-4 ↩︎A nice pocket guide to this region of America.
- [26]Native American Ethnobotany — Moerman. D. · Timber Press. Oregon. · 1998 · ISBN 0-88192-453-9 ↩︎Very comprehensive but terse guide to the native uses of plants. Excellent bibliography, fully referenced to each plant, giving a pathway to further information. Not for the casual reader.
- [27]A Field Guide to Medicinal Plants. Eastern and Central N. America. — Foster. S. & Duke. J. A. · Houghton Mifflin Co. · 1990 · ISBN 0395467225 ↩︎A concise book dealing with almost 500 species. A line drawing of each plant is included plus colour photographs of about 100 species. Very good as a field guide, it only gives brief details about the plants medicinal properties.
- [28]The Encyclopedia of Medicinal Plants — Chevallier. A. · Dorling Kindersley. London · 1996 · ISBN 9-780751-303148 ↩︎An excellent guide to over 500 of the more well known medicinal herbs from around the world.
- [29]A Dictionary of Plants Used by Man. — Usher. G. · Constable · 1974 · ISBN 0094579202 ↩︎Forget the sexist title, this is one of the best books on the subject. Lists a very extensive range of useful plants from around the world with very brief details of the uses. Not for the casual reader.
- [30]Vegetable Gums and Resins. — Howes. F. N. · Faber · ISBN 81-88818-17-8 ↩︎A very good book dealing with the subject in a readable way.
- [31]Economic Botany. — Hill. A. F. · The Maple Press · 1952 · ISBN - ↩︎Not very comprehensive, but it is quite readable and goes into some detail about the plants it does cover.
- [32]Vegetable Tannins — Rottsieper. E.H.W. · The Forestal Land, Timber and Railways Co. Ltd. · 1946 · ISBN - ↩︎A fairly detailed treatise on the major sources of vegetable tannins.
- [33]Identification Guide to the Trees of Canada — Lauriault. J. · Fitzhenry and Whiteside, Ontario. · 1989 · ISBN 0889025649 ↩︎Very good on identification for non-experts, the book also has a lot of information on plant uses.
- [34]An Illustrated Flora of the Northern United States and Canada — Britton. N. L. Brown. A. · Dover Publications. New York. · 1970 · ISBN 0-486-22642-5 ↩︎Reprint of a 1913 Flora, but still a very useful book.