YAHR, REBECCA. Duke University, Department of Botany, Durham, NC 27708. - Post-fire recovery of terrestrial lichens in Florida scrub, with emphasis on Cladonia perforata.
Prescribed fire is a common tool in the maintenance of natural
landscapes and high diversity in Florida scrubs, plant communities
well known for supporting many fire adapted endemic plants and
animals. However, the role of fire in these lichen communities has
not been studied. Cladonia perforata, an endangered terrestrial
lichen, co-occurs with several other congeners on bare sand of
endemic-rich rosemary scrub. A prescribed fire at Archbold Biological
Station on the southern end of the Lake Wales Ridge impacted three
separate populations of C. perforata in July 1993, leaving only
remnant unburned patches scattered among completely burned areas. I
investigated the rate and mode of post-fire recovery of C.
perforata in comparison with co-occurring common species in order
to inform management decisions consistent with maintenance of these
lichen populations. Detailed GPS maps of individual patches of this
lichen were made in January 1997 and compared with those made in
August 1999. Abundance of all lichen species was monitored yearly
during the winters of 1997-1999. Although all of the other terrestrial
species in the same habitat recovered from juvenile stages, no
juvenile forms of C. perforata were recorded. The area
occupied by C. perforata increased by more than 200% on
average, over the three sites. However, population growth (abundance
measures for all species) is so far too slow to have documented and
did not change markedly over this interval. Therefore, dispersal of
unburned C. perforata into burned areas may be the primary
method of short-term population recovery.
Key words: Cladonia perforata, Florida scrub, lichen, post-fire recovery, recolonization