Premium
Importance of woody debris in seed germination of Tipularia discolor (Orchidaceae)
Author(s) -
Rasmussen Hanne N.,
Whigham Dennis F.
Publication year - 1998
Publication title -
american journal of botany
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.218
H-Index - 151
eISSN - 1537-2197
pISSN - 0002-9122
DOI - 10.2307/2446418
Subject(s) - germination , biology , orchidaceae , seedling , deciduous , botany , woody plant , cunninghamia , coarse woody debris , habitat , agronomy , ecology
Concerns about declining populations of terrestrial orchids make it important to identify the environmental factors crucial to seedling recruitment. This study shows that seedlings of Tipularia discolor (cranefly orchid) primarily occur on decomposing wood. Extensive searches of decomposing logs and stumps in mature and successional forests revealed seedlings at 24 sites, of which 15 could be identified as originating from seven different deciduous trees and one conifer. Seeds were planted in natural habitats to test the hypothesis that germination requires decomposing wood. In one experiment, seeds were placed into soil at sites where adult plants were abundant; no germination resulted. In a second experiment, germination of seeds sown in ambient soil was compared with sowings in plots amended with decomposing wood collected from a stump where spontaneous seedlings grew. Germination was much more frequent in plots amended with decomposing wood. We conclude that germination of T. discolor is stimulated in substrates that contain decomposing wood; judging from the occurrence of spontaneous seedlings, wood from at variety of tree species offer a suitable substrate.