<PAGE>

                                                                      EXHIBIT 21


                         SUBSIDIARIES OF THE REGISTRANT


Sylvan Inc., a Nevada corporation, has the domestic and international
subsidiaries listed below. All are wholly owned except as noted. Certain
international subsidiaries are not named because they are not significant in the
aggregate. Sylvan Inc. has no parent.

<TABLE>
<CAPTION>
                                                                  State/Country of Incorporation
                                                                  ------------------------------
<S>                                                               <C>
Quincy Corporation                                                            Florida
Somycel S.A.                                                                  France
Sylvan Africa (Pty) Ltd.                                                      South Africa
Sylvan America, Inc.                                                          Nevada
Sylvan America, Inc.                                                          Pennsylvania
Sylvan Bioproducts, Inc.                                                      Pennsylvania
Sylvan Communications, Inc.                                                   California
Sylvan Denmark                                                                Denmark
Sylvan Export Corporation                                                     Barbados
Sylvan Foods, Inc.                                                            Pennsylvania
Sylvan Foods (France) S.A.                                                    France
Sylvan Foods (Netherlands) B.V.                                               the Netherlands
Sylvan Fungisem, S.A. (a)                                                     Spain
Sylvan Holdings Pty Ltd. (b)                                                  Australia
Sylvan Horst B.V. (c)                                                         the Netherlands
Sylvan Hungaria Kft.                                                          Hungary
Sylvan Hungary Compost Producing and Trading Ltd.                             Hungary
Sylvan Ireland                                                                Ireland
Sylvan Italia S.r.l.                                                          Italy
Sylvan Nederlands B.V.                                                        the Netherlands
Sylvan Pilz AG                                                                Switzerland
Sylvan Spawn Canada, Ltd.                                                     Canada
Sylvan Polska Sp. z.o.o.                                                      Poland
Sylvan Spawn Laboratory Hungary Ltd.                                          Hungary
Sylvan Spawn Limited                                                          England
Sylvan Tarim Urunleri Sanayi Ve Ticaret Limited Sirketi (d)                   Turkey
Tartarin S.A.                                                                 France
White Queen Ltd.                                                              England
</Table>


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(a)   50% ownership
(b)   49% ownership
(c)   75% ownership
(d)   60% ownership



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