Corrections to The Sibley Guide to Trees


Here are page-by-page corrections and changes for The Sibley Guide to Trees. This listing will be updated periodically as issues come to my attention. Please feel free to leave comments or send me an email if you notice anything that is not listed here.

inside front cover – The two-letter abbreviation for Nunavut should be NU (not NV). The USDA hardiness zones map could be replaced with an updated map by National Arbor Day Foundation to better reflect current climate. You can also see a map that includes hardiness zones for Canada as well as the US, although it is based on 1990 zones.

p vi – Myrtle Family should be listed as page 109

p 3 – California Torreya, the common and scientific names should be justified left

p 28 – Red Pine needs a new name to distinguish it from Japanese Red Pine. I propose American Red Pine.

p 41 – Hemlock intro – twig with pollen cones and seed cone caption should not refer to female flowers, instead should say “female seed cones tiny, green or purplish at twig tip”

p 43 – Scientific name of Mountain Hemlock should be Tsuga mertensiana

p 49 – Both Serbian Spruce and Oriental Spruce have maximum height lower than “typical” height. This is because the maximum heights listed in the guide are for trees growing in North America, while “typical” heights in this case come from information about the trees in their native range. The “typical” height should also refer only to North American trees, and therefore should be lower. Presumably Serbian Spruce is usually less than 40′ tall in North America, and Oriental Spruce usually less than 60′ tall.

p. 49 – Serbian Spruce, “straddlng” should be “straddling.”

p 83 – scientific name of California Fan Palm should be Washingtonia filifera

p 102 – Scientific name of London Planetree more commonly used is Platanus x hispanica

p 105 – Parrotia has only one t

p 143-149 – Hickories, terminology for describing nuts as “ribbed” or “angled” needs to be clarified and corrected (a detailed post about this is here).

p 146 – Black Hickory caption should say “husk very similar to Pignut…”; Sand Hickory, captions should read “fruit similar to Pignut…” and “twigs similar to Pignut…”

p 179 – Tanoak – caption at bottom right should specify “pale underleaf conspicuous among dense, dark foliage”

p 189 – Southern Red Oak leafy twig, the caption saying “acorn identical to Southern Red Oak” should instead say “acorn identical to Cherrybark Oak”

p 227 – Tung-Oil Tree – leaves should be larger

p 232 – Eastern Cottonwood – range map updated to add Florida and northeastern locations (new map here)

p 250 – Hollyleaf Buckthorn is often split into several species, and in that treatment the only tree-like species is known as Red-berry Buckthorn (or Island Redberry) Rhamnus pirifolia, found on the Channel Islands. See the Jepson manual for details.

p 252 – Glossy False-buckthorn includes the three leaves at the top of the column and the map at the bottom. The yellow box of text and the three leaves immediately below that are Ceanothus. The map should be moved up above the box text to make clear that it represents the range of Glossy False-buckthorn.

p255 – Rose Family Intro, near bottom of column 1 should say “Plums and Cherries (Prunus) page 256” [not page 254]

p 295 – USDA Plants database says Photinia serratifiolia is Taiwanese Photinia, while Chinese is P. davidiana

p 302 – Slippery Elm, in the third sentence “fragrant” is misspelled.

p 324 – last paragraph column 1: “One other species of Soapberry is found in North America” should read “One other species of soapberry found in North America is often tree-like”

page 332 – Intro to maples, the third paragraph begins “All maples have palmately compound leaves…” This should instead say “Nearly all maples have palmately lobed leaves…” And could go on to elaborate that a few species have the leaves so deeply lobed that they are compound, and Boxelder is unique among the maples in having pinnately compound leaves.

p 334 – Red Maple, map should include the southeastern corner of Newfoundland.

p 336 – Silver Maple, map is incorrect. The range should not extend as far north in Canada, etc. Ron Pittaway (pers. comm.) reports that Silver Maple is largely restricted to river floodplains in southern Ontario, and hybridizes commonly with Red Maple at the northern edges of its range. A map showing the approximate native range is in the Silvics Manual (note that cultivation has extended the range beyond this map in many areas).

p 338 – Sugar Maple, range should extend farther north and northeast to approximately match Red Maple (fide Ron Pittaway)

p 344 – Striped Maple, in the yellow box the word “between” is misspelled

p 345 – Mountain Maple underleaf should be rotated with stem down, (same for Vine Maple)

p 346 – Boxelder, range should extend to include all of southern Ontario north to Ottawa (fide Ron Pittaway). Note that the map of native range in the Silvics Manual shows none growing north of New York state, so the Ontario trees must be a recent range expansion, presumably escaped from cultivation.

p 392 – First line of text – capitalize Paulownia family

p 393 – Aralia Family, add a sentence saying “Castor-Aralia (p 322) is also a member of this family and should be placed here.” [and in a future edition it will be]


Entries for Chilopsis, Chionanthus, Chinese-Fir, and Chinkapin, at the bottom of column 1 page 418, are out of order and should all be moved up a few entries to fit in proper alphabetical order.

Missing entry for Maple, Silver – pg. 336

Myrtle family should be pg. 109

Pignut should say pg. 145

Rose Family should say pg. 254

And it is suggested (see comments below) that species like Northern White-Cedar and Western Redcedar should have an entry in the index under “cedar”. [and presumably there are other examples like this]

Thanks to Rex Rowan, Ron Pittaway, Larry Sansone, and others for pointing out errors.

24 thoughts on “Corrections to The Sibley Guide to Trees”

  1. p302 – Slippery Elm – "fragramt" should be "fragrant"

    A more general issue is the index. I've found three problems so far.

    The minor one is there are a few entries I've found (so there may be more) where the page entry is off by one or two. I presume the page order changed a bit after the index was created.


    Pignut p145 is on p148
    Rose Family p253 is on p354

    This also happens in some of the family intros too e.g. Rose family intro says "Plums and Cherries on p254" but they're on page p256.

    Another minor issue is names mentioned in the text but not in the index

    p146 – Sand Hickory caption text – "twigs similar to Sweet Pignut" but neither Sweet Pignut nor Pignut, Sweet is in the index.

    The second is the indexing of common names of some trees especially when the name includes a "family name". For example the Western Redcedar and Northern White-Cedar are not indexed under Cedar which for the naive user is not expected (even though they're Cypresses not Cedrus). This is fixed for Douglas-fir which is under Fir even though it isn't (common names: don't you love then!).

    A reviewer made a similar comment in a review in the Cleveland Plain Dealer where he mentions "What Sibley calls 'American Larch' I've always called 'Tamarack' or 'hatmatack.' The guide gives three alternate names for the tree – tamarack, hackmatack and black larch – but the index only includes Hackmatack. The welter of names isn't Sibley's fault, but he and his editors could have sorted them better."

    Finally on p322 The Castor-Aralia is in the Aralia family but it's split off from the main Aralia family entry on p393 and not indexed under Aralia in the index. It would be easy to miss if I hadn't noticed it.

  2. Hi Kevin. Thanks for these comments. I've updated the list above. And I just have two points in response to continue the discussion about common names: Most species have many different common names, and I had limited space, so I had to choose two or (rarely) three or four alternate names to highlight. In most cases I tried to choose the most frequently-used, but I would tend to leave out minor variations of the primary name, and I suspect that's why I didn't include "Sweet Pignut Hickory" since the species is named "Pignut Hickory". It would be great to have a complete listing of alternate names, but it simply wouldn't fit in this book. If anyone knows of a good comprehensive source please let me know.
    The index includes Douglas Fir under "Fir" because the alternate name listed is "Douglas Fir" without a hyphen. Species like Western Redcedar (compound word) and Northern White-Cedar (hyphenated) would not be picked up for the index. This is just an explanation, not a defense, and I agree that those species should appear under Cedar.

  3. Wow, if this is it, I'm happy. And happy NYT Bestseller List, Dave! We're behind "What to Expect…" and "Skinny Bitch," but we'll keep climbing!

  4. I am very disappointed in the Guide to Trees.
    Nothing in the reviews that I read prior to purchase indicated a lack of information regarding trees of southern Florida. After buying the book I did note the disclaimer in the Introduction. But that disclaimer was mild compared to the actual situation.
    Many trees that are found regularly in central and northern Florida and even southern Alabama are not included in the Guide. Palms are almost totally ignored. Banyan trees are absent as are the common ficus. No mention of Bottlebrush. And these are observations made in only a couple of days.
    I do hope that the author will research and publish a supplement that will contain more complete information about North American trees.

    1. Thanks for these comments, Phil. I’m sorry that you are disappointed. I think the book does include all of the native species of trees found in the US south to and including northern Florida. All of the species you mention are cultivated, not native, and I considered those less of a priority for my research and for inclusion in the guide. The situation in coastal California is the same, with a lot of commonly cultivated species that are not included in the guide.
      I am currently working on a list of additional species and info and I hope to post that in the not-too-distant future.

  5. Thomas W Thomas

    I would request that you review the entire presentation on the Saw-Palmetto found on page 83.

    What is shown is not what lives around me on Fripp Island, SC. The Saw-Palmetto rarely gets more than two to three feet off the ground and most usually its trunk is almost parallel to the ground. Also, its stalk, holding its leaflets, are lined with a saw edge that will surely cut to the bone if one is not careful.

    I suspose what we have may be a variation, but your notes fail to mention the very part of the tree that gives it its name, the saw like edges on its stalk.

    Thanks for looking into this.

    I continue to enjoy your books and am the proud owner of Guide to Birds and Guide to Birds Life & Behaivor.

    Very Truly yours,

    Thomas W Thomas

    1. Thanks for these comments Thomas. There is at least one place in Florida where Saw-Palmetto grows into a tree-like form as shown in my illustration. Normally it has a prostrate trunk and rises just a few feet off the ground, and would not qualify for inclusion in a guide to trees, and I should probably put more emphasis on the fact that it is rarely tree-like. And I will also make a note to mention the origin of the “saw” in the name whenever I do a revision.

  6. I love the Sibley Guide to Trees! I am a teacher/naturalist with a background in forestry and botany, and I find this book to be a tremendous resource. Its fresh approach to field identification has been long overdue. Are there any plans in the works for “eastern” and “western” editions? A smaller, more portable format would be a boon in thr field.

  7. Page 336, (Silver Maple) You have already noted that the map is incorrect. Add to that the map’s notation references Red Maple rather than Silver.

    1. Thanks for the comment, Roy. Actually the reference to Red Maple there was intended to compare and contrast the preferred habitat of the two species – Silver Maple along riverbanks (with moving water), Red Maple in swamps (meaning low-lying areas with damp soil or very slow-moving or stagnant water) – but I can see how the terse wording could cause confusion.

  8. I have recently purchased and begun using the Sibley Guide to Trees. So far I’ve found it useful, and it has enabled me to identify a non-native tree in my neighborhood that several other field guides didn’t help with. Thank you for the detailed and careful illustrations. However, I would urge you to revise your pages on Populus deltoides and Populus fremontii (sometimes fremonti)(pp. 232 and 233). I know you have already corrected the range map for P. deltoides, but even that correction definitely does not fix the problem. For a long time, P. deltoides and its several Southwestern varieties or subspecies, depending on whom you consult, has been confused with P. fremontii. Your new range map for P. deltoides unfortunately completely ignores the fact that most botanists now recognize that a subspecies or variety of P. deltoides, P. deltoides ssp wislizeni, is found all along the Rio Grande River. The Rio Grande or Valley cottonwood, as it is commonly called, is the primary cottonwood of New Mexico and other neighboring areas of the Southwest, but your range map doesn’t even show P. deltoides west of east Texas, much less its true extent in the Southwest. Old and incorrect range maps show P. fremontii (or fremonti) as the primary cottonwood of New Mexico, but that is not the case. P. deltoides ssp. wislizeni is generally agreed to be the cottonwood of western Colorado, most of New Mexico, far west Texas, northern Arizona, and most of the Four Corners area. True, these two Southwestern poplars are very similar, but they are distinct, and it is important, I think, in a future revision of your admirable book, to correct the range maps for P. deltoides and for P. fremontii. The best source for the taxonomy of Populus is James Eckenwalder, who laid out the taxonomy of North American cottonwoods in the Journal of the Arnold Arboretum in l977. However, for some reason long-standing errors of misidentification of P. deltoides subspecies in the Southwest have remained in the literature and get repeated.

    1. Sandra,
      Thanks for your comment. I haven’t read the Eckenwalder paper and will try to do that soon, but my initial response is that all of these taxa are so closely-related it really becomes a matter of personal preference for weighing the evidence and splitting and grouping them. I followed the USGS treatment of considering wislizeni part of fremontii in the west, and deltoides a separate species in the east. To me that treatment makes more sense biogeographically, and matches the distribution of a lot of bird species. The other approach that I see used in recent publications (e.g. BONAP) is to consider fremontii just a form of deltoides and lump them all as one species. From the amateur tree-watcher’s point of view I think the differences are so small that identification of these trees beyond the general “Cottonwood group” is best left to specialists.

  9. Mr. Sibley,

    Thank you for your reply. I really appreciate your consideration of my comment. I understand your reluctance to delve into the small differences between the subspecies of Populus deltoides. These would be of little interest to most people seeking to identify trees. However, let me explain to you why I think it’s important for a book like yours to do justice to the very broad range of Populus deltoides in the U. S. (and Canada). Your current range map on p. 232 omits half of the U. S., the half I live in (my home is in New Mexico). We are very interested here in teaching people, especially young people, about our native riparian woodlands because they are threatened in many respects. We teach folks that the familiar and beloved trees they see around them in our river bosque (woods) are Populus deltoides (we also provide the subspecies name, but that isn’t essential. But then if they buy and use your book, they get conflicting information, as it shows no P. deltoides in New Mexico or the entire West. So they wonder whom to believe. Therefore, I recommend that you go with what BONAP does. A query to their database for P. deltoides will get you a map of the entire U.S. except for Washington State (where the cottonwoods are a different species). It seems to me that a revised version of your excellent book would provide just such a range map. You wouldn’t have to do more than perhaps list the subspecies (as BONAP will do if requested), but at least you would have a more comprehensive and accurate range map for an important native tree.


  10. One oversight: Among the common names of Alaska-cedar (Callitropsis nootkatensis, p. 73)you do not include “Yellow Cedar”. This is the ONLY common name I’ve ever heard apply to it in the Pacific Northwest (all along the Pacific coast, Oregan to Alaska), where it is be found reliably — and is considered to have high commercial value. So I think this name should at least be included in the list of common names for this specias. From my own experience, I would take it to be the primary common name.

    One error: You describe Common Juniper (Juniperus communis, p. 68) as an exotic. I was amazed, since here in my neighborhood (NW Montana) it grows everywhere, and certainly hasn’t be planted by humans in all these places. And from what I read, it is not simply naturalized from cultivated individuals either. E. C. Pielou in her Northern Evergreens treats it as a native, and says it is the most common juniper — grows from coast to coast and up into the artic circle. Also, I’ve looked at two books that talk about plants that were used by native Americans, and they both say Common Juniper was used for medicinal purposes by native peoples — mainly by inland peoples but also to some extent by coastal natives, and was considered to have some sort of spiritual value by the Haida (who lived and still to live in Haida Gawaii (Queen Charlotte Islands) off the BC coast)).
    Common Juniper occurs, of course, as a bush rather than a tree. So maybe it doesnt’ even belong in your Guide to Trees. Or maybe in its cultivated form it can become a tree — though I’ve never heard of this. If the latter is the case, then it should be at least noted that in its bush form it is a widespread native juniper.

  11. David, I entered the errata in my book, including the deletion of “Sweet” before “Pignut” in 2 locations on p. 146. Then I noticed that the same error appears in the discussion of Scrub Hickory on p. 145. Not being picky,just trying to help.

  12. Some more fixes:

    pg. 86: Saguaro has been moved from the genus Cereus to its own, now being Carnegiea giantea.

    pg. 120: Jerusalem Thorn – Parkinsoniana should be Parkinsonia.

    pg. 149: The header says “Hickories: Nutmeg Hickory and Chinese Wingnut” but this should probably be something like “Walnut Family: Hickories and Chinese Wingnut”, given that Chinese Wingnut isn’t a hickory.

    pg. 149: It also says “Hickory Family: Wingnut”. This should be changed to “Walnut Family: Wingnut” as it’s called that in the rest of the book.

    pg. 149. Platycarya should be Pterocarya.

    pg. 179. Some sources now list Tanoak as being part of its own genus, Notholithocarpus.

    pg. 244: Russian-olive: Eleagnus should be Elaeagnus.

    pg. 311: Silver Linden: Tilia petiolaris should be Tilia tomentosa or Tilia tomentosa ‘Petiolaris’.

  13. attractive book. However, I noticed that the range map for Sitka Spruce is incorrect ( page 46 ). The map in my addition show the range extending only to the southern border of Oregon. Other references indicate that Sitka Spruce extends much further south into California.

    From personal and professional experience, I have found this species as far south as the forest lands of Georgia Pacific in Fort Bragg. This tree is also found around Humboldt County spreading north to Oregon.

    Needles from this tree are particularly vexing when they fall down the back of your shirt; the name ‘needle’ is quite appropriate.

  14. Your Book is Outstanding. The maximum height of both Sweetgum and Scarlet Oak could be revised. Basket Oak too. Thank You for your wonderful book

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