Isotopic evidence indicates saprotrophy in post-fire Morchella in Oregon and Alaska
Document Type: Journal Article
Author(s): E. A. Hobbie; S. F. Rice; N. S. Weber; J. E. Smith
Publication Year: 2016

Cataloging Information

  • carbon
  • carbon sources
  • ectomycorrhizal
  • fungi
  • life history
  • Morchella
  • mycorrhiza
  • Oregon
  • post fire recovery
  • post-fire
  • Saprotrophy
  • wildfires
Record Maintained By:
Record Last Modified: June 1, 2018
FRAMES Record Number: 55168
Tall Timbers Record Number: 33104
TTRS Location Status: Not in file
TTRS Call Number: Available
TTRS Abstract Status: Okay, Fair use

This bibliographic record was either created or modified by the Tall Timbers Research Station and Land Conservancy and is provided without charge to promote research and education in Fire Ecology. The E.V. Komarek Fire Ecology Database is the intellectual property of the Tall Timbers Research Station and Land Conservancy.


We assessed the nutritional strategy of true morels (genus Morchella) collected in 2003 and 2004 in Oregon and Alaska, 1 or 2 y after forest fires. We hypothesized that the patterns of stable isotopes (d13C and d15N) in the sporocarps would match those of saprotrophic fungi and that radiocarbon (D14C) analyses would indicate that Morchella was assimilating old carbon not current-year photosynthate. We compared radiocarbon and stable isotopes in Morchella with values from concurrently collected foliage, the ectomycorrhizal Geopyxis carbonaria (Alb. & Schwein.) Sacc., the saprotrophic Plicaria endocarpoides (Berk.) Rifai, and with literature to determine isotopic values for ectomycorrhizal or saprotrophic fungi. Geopyxis, Plicaria and Morchella, respectively, were 3 parts per thousand, 5 parts per thousand and 6 parts per thousand higher in 13C than foliage and 5 parts per thousand, 7 parts per thousand and 7 parts per thousand higher in 15N. High 15N enrichment in Morchella indicated that recent litter was not the primary source for Morchella nitrogen, and similar 13C and 15N enrichments to Plicaria suggest that Morchella assimilates its carbon and nitrogen from the same source pool as this saprotrophic fungus. From radiocarbon analyses Morchella averaged 11 ± 6 y old (n = 19), Plicaria averaged 17 ±5 y old (n = 3), foliage averaged 1 ±2 y old (n = 8) and Geopyxis (n = 1) resembled foliage in D14C. We conclude that morels fruiting in post-fire environments in our study assimilated old carbon and were saprotrophic. © 2016 by the Mycological Society of America.

Online Link(s):
Hobbie, E. A., S. F. Rice, N. S. Weber, and J. E. Smith. 2016. Isotopic evidence indicates saprotrophy in post-fire Morchella in Oregon and Alaska. Mycologia, v. 108, no. 4, p. 638-645. 10.3852/15-281.