Willow water is a traditional method to extract the rooting hormone
indolebutyric acid from
willow
Willows, also called sallows and osiers, from the genus ''Salix'', comprise around 400 speciesMabberley, D.J. 1997. The Plant Book, Cambridge University Press #2: Cambridge. of typically deciduous trees and shrubs, found primarily on moist so ...
(''Salix'') trees, which are believed to be present in sufficient quantities to stimulate root growth.
[Ohio State University Extension, ]Willow Water for Bonsai
Bonsai4me
References
Horticulture
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