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Re: Sylphium perfoliatum (cup plant)

Silphium [I believe this is the proper spelling] is a composite, and MOST 
[not all] composites germinate readily from dry seed without special 
treatment. Seed sown outdoors now is likely to germinate. If you start 
seed indoors, it will probably germinate just as well.  However, going 
naturally from cold to warm temperatures is the most inclusive method for 
temperate-zone seeds.

Loren Russell, Corvallis, Oregon
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