Demography of scrub plum (Prunus geniculata) at Carter Creek, Lake Wales Ridge National Wildlife Refuge, 2001-2013, in relation to fire and felling

At the Carter Creek unit of the Lake Wales Ridge National Wildlife
Refuge, we collected demographic data annually on scrub plum (Prunus
geniculata), a federally endangered shrub. We initially selected 903
plants (tagged and GPS'd) distributed among 12 management units in
February 2001, a minimum of 65 plants per management unit. We worked
with United States Fish and Wildlife Service (USFWS) staff and a crew
from The Nature Conservancy (TNC) to impose three management
treatments on a unit basis (4 replicate units) in 2001 (finishing in
August): control, chain-saw felling of large oaks, and chain-saw
felling followed by prescribed burns. The treatments also served as
the basis for vegetation sampling and demographic research on other
species (Rickey et al. 2013). Beginning in 2001 and continuing through
2008, we collected annual data (in February) on each marked plant,
including survival status, life history stage, height, maximum crown
diameter, and reproductive structures. We also scoured areas near
plants for new seedlings. We subsampled plants from 2009-2012, and
then re-censused all plants in 2013. We also noted fire severity in
2001, 2007, and 2009 in four categories for each plant. Analyses
through 2007 (Menges and Weekley 2013) showed that scrub plum had
extremely high annual survival (98%) but minimal seedling recruitment.
Scrub plum had high survival in all four burn treatments, although
severely burned plants were more likely to die. Fire benefited scrub
plum as plants resprouted vigorously, increased stem numbers
post-fire, and had higher flower production 2-3 years after fires.
Between fires, plants increased in height and diameter but retained
fewer stems. We concluded that chainsaw felling of oaks did not have
strong effects on scrub plum and could be a useful management tool,
but we also emphasized the primacy of fire as an ecological
disturbance and management treatment in this sandhill ecosystem.