Wow nice article (within the link you posted):
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These species which have been listed by regional
conservation nurseries as benefiting from sweating, under
certain conditions include:
• Green ash
• Bur oak
• Hackberry
• Chokecherry
• Juneberry
• Amur maple
• Ussurian (Harbin) pear
• Skunkbush sumac
• Birch
• Mountain ash
• Hawthorns
Trees and shrubs that remain dormant for most or all of the
first growing season will probably die before the next growing
season. If you have had problems in past years with getting
some of these species to leaf out, consider the technique of
sweating.
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So basicly i had to sweat my collected birch, it still survived but leaved out very late (almost too late).