New York Metropolitan Flora

Nomenclature

Salix L., Sp. Pl. 2: 1015. 1753. Gen. Pl., ed. 5, 477. 1754. TYPE: Salix alba L. designated by Britton & Brown (1913) or Salix pentandra Hitchcock & Green (1929)

Vetrix Raf., Amer. Monthly Mag. & Crit. Rev. 1: 439. 1817. TYPE: Not designated.

Vimen Raf., Amer. Monthly Mag. & Crit. Rev. 1: 439. 1817. TYPE: Not designated.

Oisodix Raf., Amer. Monthly Mag. & Crit. Rev. 1: 439. 1817. TYPE: Not designated.

Usionis Raf., Alsogr. Amer. 14. 1838. TYPE: Not designated.

Ripselaxis Raf., Alsogr. Amer. 14. 1838. TYPE: Ripselaxis herbacea (L.) Raf. (=Salix herbacea L.).

Nectolis Raf., Alsogr. Amer. 15. 1838. TYPE: Not designated.

Amerina Raf., Alsogr. Amer. 15. 1838. TYPE: Not designated.

Diplusion Raf., Alsogr. Amer. 15. 1838. TYPE: Not designated.

Knafia Opiz, Seznam 56. 1852. TYPE: Unknown.

Lusekia Opiz, Seznam 61. 1852. TYPE: Unknown.

Key to the species of Salix

1. Leaves without apparent sharp teeth...2
1. Leaves with teeth...8

2. Leaves mostly glabrous beneath (excluding few hairs along main vein)...3
2. Leaves hairy throughout beneath...4

3. Small shrub, to 4 ft.; finely reticulate venation (3rd-level veins apparent); fruit glabrous; rare...Salix pedicellaris
3. Large shrub, over 4 ft.; without finely reticulate venation (3rd-level veins not readily visible); fruit hairy; common...Salix discolor

4. Leaves with white hairs beneath...Salix candida
4. Leaves with gray or red hairs beneath...5

5. Leaves with inrolled margins...Salix humilis
5. Leaves without inrolled margins...6

6. Leaves with sparse red or gray hairs beneath...Salix discolor
6. Leaves covered with gray hairs beneath...7

7. Leaves mostly 2.5 cm wide or less; scales subtending fruit pale...Salix bebbiana
7. Leaves (many) 2.6 cm wide or more; scales subtending fruit dark...Salix caprea

8. Leaves mostly glabrous beneath (excluding few hairs along main vein)...9
8. Leaves hairy beneath...19

9. Leaves opposite or subopposite...Salix purpurea
9. Leaves alternate...10

10. Petioles with glands (especially toward top)...11
10. Petioles lacking glands...13

11. Leaves with long-acuminate apices...Salix lucida
11. Leaves with acute-acuminate apices...12

12. Scales subtending fruit long-hairy throughout; native...Salix serissima
12. Scales subtending fruit long-hairy chiefly near the base; alien...Salix pentandra

13. Leaves glaucous beneath...14
13. Leaves green beneath...18

14. Leaves with teeth widely spaced, 3 or fewer per cm...Salix discolor
14. Leaves with teeth closely spaced, 4 or more per cm...15

15. Leaves mostly 1.9 cm wide or more...16
15. Leaves mostly 1.8 cm wide or less...17

16. Stipules large, persistent; small or no glands on teeth; scales subtending fruit dark...Salix eriocephala
16. Stipules small or lacking; prominent glands on teeth; scales subtending fruit pale...Salix fragilis

17. Leaves with long-acuminate and often falcate apices; twigs/branches pendulous; fruit glabrous...Salix babylonica
17. Leaves with acute-acuminate apices; twigs not pendulous; fruit hairy...Salix petiolaris

18. Leaves with teeth widely spaced, 5 or fewer per cm; usually lacking stipules; fruit hairy...Salix exigua
18. Leaves with teeth closely spaced, 6 or more per cm; usually with prominent stipules; fruit glabrous...Salix nigra

19. Leaves mostly 1.8 cm wide or less...20
19. Leaves mostly 1.9 cm wide or more...21

20. Current year’s twigs yellow-tan; fruit glabrous...Salix alba
20. Current year’s twigs brown-gray; fruit hairy...Salix sericea

21. Leaves with sparse red or gray hairs beneath...Salix discolor
21. Leaves covered with gray hairs beneath...22

22. Leaves mostly 2.5 cm wide or less; scales subtending fruit pale...Salix bebbiana
22. Leaves (many) 2.6 cm wide or more; scales subtending fruit dark...Salix caprea

List of Salix Species

Other Links

Interactive Salix key:

http://aknhp.uaa.alaska.edu/botany/salix-salicaceae-identification-using-intkey/

References to Salix

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• Argus, G. W. 1974. An experimental study of hybridization and pollination in Salix (willow). Canad. J. Bot. 52: 1613-1619.
• Argus, G. W. 1984. Salix occidentalis Walter, the correct name for S. tristis Aiton (Salicaceae). Brittonia 36: 328-329.
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• Binns, W. W.; Blunden, G.; Woods, D. L. 1968. Distribution of leucoanthocyanidins, phenolic glycosides, and amino-acids in leaves of Salix species. Phytochemistry 7: 1577-81.
• Blackburn, K. B.; Heslop-Harrison, J. W. 1924. A preliminary account of the chromosomes and chromosome behavior in the Salicaceae. Ann. Bot. (London) 38: 361-378.
• Brunsfeld, S. J.; Soltis, D. E.; Soltis, P. S. 1991. Patterns of genetic variation in Salix section Longifoliae (Salicaceae). Amer. J. Bot. 78(6): 855-69.
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• Chmelar, J. 1981. Taxonomic importance of nectary structure in the genus Salix. Folia Dendrol. 8: 5-23. (In Chech; English summary)
• Chmelar, J. 1977. Taxonomic importance of capsule seed number in the genus Salix L. Cas. Slezsk. Muz., C, Dendrol. 26(1): 1-7. (In Chech; English summary)
• Chong, D. K. X.; Zsuffa, L.; Aravanopoulos, F. A. 1995. Genetic relationship between Salix exigua and other North American willows (Salix L.): evidence from allozyme variation. Biochem. Syst. Ecol. 23: 767-71.
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• Denneler, B; Bergeron, Y.; Begin, Y. 1999. An attempt to explain the distribution of the tree species composing the riparian forests of Lake Duparquet, southern boreal region of Quebec, Canada. Canad. J. Bot. 77: 1744-1755.
• Dionigi, C. P. 1982. The effects of soil waterlogging on the growth and distribution of Salix nigra and S. exigua (Salicaceae) plants in the Atchafalaya River basin of Louisiana. M.S. Thesis Univ. Southwestern Louisiana, Lafayette,
• Dionigi, C. P.; Mendelssohn, I. A.; Sullivan, V. I. 1985. Effects of soil waterlogging on the energy status and distribution of Salix nigra and S. exigua (Salicaceae)in the Atchafalaya River basin of Louisiana. Amer. J. Bot. 72(1): 109-19.
• Dorn, R. D. 1975. A systematic study of Salix section Cordatae in North America. Canad. J. Bot. 53(15): 1491-522.
• Dorn, R. D. 1976. A synopsis of American Salix. Canad. J. Bot. 54: 2769-2789.
• Dorn, R. D. 1995. A taxonomic study of Salix section Cordatae subsection Luteae (Salicaceae). Brittonia 47(2): 160-74.
• Dorn, R. D. 1975. Cytological and taxonomic notes on North American Salix. Madrono 23: 99. (see also Diss. Abstr. Int., B 35(7):3182. 1975.)
• Dorn, R. D. 1994. North American Salix (Salicaceae): Typification and notes. Phytologia 77(2): 89-95.
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• Falinski, J. B. 1980. Changes in the sex- and age-ration in populations of pioneer dioecious woody species (Juniperus, Populus, Salix) in connection with the course of vegetation succession in abandoned farmlands. Ekologia Polska 28: 327-65.
• Fernald, M. L. 1946. Technical studies on North American plants. II. Difficulties in North American Salix. Rhodora 48: 13-6,27-49.
• Fernald, M. L. 1904. Two northeastern allies of Salix lucida. Rhodora 6: 1-8.
• Fernald, M. L. 1909. Salix pedicellaris and its variations. Rhodora 11: 157-62.
• Fernald, M. L. 1912. Salix serissima in southern Connecticut. Rhodora 14: 80.
• Fisher, M. J. 1928. The morphology and anatomy of the flowers of the Salicaceae I. Amer. J. Bot. 15: 307-326.
• Fisher, M. J. 1928. The morphology and anatomy of the flowers of the Salicaceae II. Amer. J. Bot. 15: 372-394.
• Fisher, M. J. 1923. The anatomy of the flower of the Salicaceae. Ph.D. Dissertation Cornell Univ., Ithaca, NY165 p.
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• Fontana, A. 1962. Researches on the mycorrhizae of the genus Salix. Allionia 8: 67-85.
• Forbes, F. F. 1909. Salix subsericea a distinct species. Rhodora 11: 9-12.
• Fox, J. F. 1992. Pollen limitation of reproductive effort in willows. Oecologia 90: 283-7.
• Glenn, Steven D. 1995. Honeybees (Apis sp.) and bumblebees (Bombus sp.) visiting various willow ({Salix spp.) flowers.
• Glenn, Steven D. 1996. Bee (Andrena sp.) visiting Salix flowers.
• Graenicher, S. 1900. The fertilization and insect visitors of our earliest entomophilous flowers. Bull. Wisconsin Nat. Hist. Soc. 1: 73-84.
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• Hosner, J. F. 1958. The effects of complete inundation upon seedlings of six bottomland tree species. Ecology 39: 371-3.
• Hunter, J. C.; Mattice, J. A. 2002. The spread of woody exotics into the forests of a northeastern landscape, 1938-1999. J. Torrey Bot. Soc. 129: 220-227.
• Jarvis, C. E. 1992. Seventy-two proposals for the conservation of types of selected Linnaean generic names, the report of Subcommittee 3C on the lectotypification of Linnaean generic names. Taxon 41: 552-83.
• Julkunen-Tiitto, R. 1986. A chemotaxonomic survey of phenolics in leaves of northern Salicaceae species. Phytochemistry 25: 663-668.
• Karrenberg, S.; Suter, M. 2003. Phenotypic trade-offs in the sexual reproduction of Salicaceae from flood plains. Amer. J. Bot. 90: 749-754. (5)
• Kawase, M. 1964. Centrifugation, rhizocaline and rooting in Salix alba L. Physiol. Pl. (Copenhagen) 17: 855-65.
• Kehl, A. et.al. 2008. Genotypical and multiple phenotypical traits discriminate Salix x rubens Schrank clearly from its parent species. Pl. Syst. Evol. 275: 169-179.
• Kim, K. H.; Zsuffa, L.; Keeney, A.; Mosseler, A. 1990. Interspecific and intraspecific variation in pollen morphology in four species of Salix. Canad. J. Bot. 68: 1497-501. (French summary)
• Koncalova, M. N.; Jicinska, D. 1982. Ecological factors of flowering and pollen quality in three willow species. Folia Geobot. Phytotax. 17(2): 197-205.
• Kopp, R. F. et.al. 2002. Collection and storage of pollen from Salix. Amer. J. Bot. 89: 248-252.
• Krichfalushii, V. V.; Holyshkin, L. V. 1985. Chromosome numbers of representatives of the genus Salix. Ukrayins'k Bot. Zhurn. 42: 33-34. (In Ukranian)
• Krizo, M. 1977. Contribution to the knowledge of pollen grains of hybrids in the genus Salix L. Folia Dendrol. 3: 55-74. (In Chech; English, German, & Russian summaries)
• Kuzovkina, Y. A.; Knee, M.; Quigley, M. F. 2004. Effects of soil compaction and flooding on the growth of 12 willow (Salix L.) species. J. Environ. Hort. 22: 155-160.
• Lamb, G. N. 1915. Willows: Their growth, use and importance.
• Lautenschlager, F. D. et.al. 1993. On the distinction of Salix fragilis from its hybrid Salix x rubens. Bauhinia 11: 35-36. (In German)
• Leskinen, E.; Alstrom-Rapaport, C. 1999. Molecular phylogeny of Salicaceae and closely related Flacourtiaceae: evidence from 5.8S, ITS 1 and ITS 2 of the rDNA. Pl. Syst. Evol. 215: 209-227.
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• Malyutina, E. T.; Malyutin, K. G. 1975. Morphology and evolution of Salix L. flower. (Abstract only)
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• Mosseler, A. 1990. Hybrid performance and species crossability relationships in willows (Salix). Canad. J. Bot. 68: 2329-38. (French summary)
• Mosseler, A. 1989. Interspecific pollen-pistil incongruity in Salix. Canad. J. Forest Res. 19: 1161-8.
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• Tesky, J. L. 1993. Salix bebbiana. ()
• Tesky, J. L. 1992. Salix nigra. ()
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