Microhabitat of Critically Endangered
Lupinus aridorum (Fabaceae)
at Wild and Introduced Locations in Florida Scrub*
Rare Plant Conservation Program
Juliet Rynear, Rare Plant Specialist
Dr. Matthew Richardson
Photo by Cindy Campbell
*Richardson, Rynear, Peterson. 2014. Microhabitat of Critically Endangered Lupinus aridorum (Fabaceae) at Wild
and Introduced Locations in Florida Scrub. Plant Ecol (2014) 215:399–410.
Research since 1986
~ Lupinus aridorum
• Propagation protocols
• Testing fungicides, insecticides, larvicides, fertilization
• Species biology
– Seed dormancy
– Population genetics
– Symbiotic interactions with soil organisms
– Root exudates
• Introduction protocols
• Monitoring protocols for introduced populations
Photo by Bill Parken
Scrub Lupine - Lupinus aridorum
McFarlin ex Beckner (Fabaceae)
Photo by Brad Kolhoff
 Florida endemic
 Scrub community
 Short-lived perennial
 Unifoliolate
 Leaves appear silver covered in fine hairs
 Long taproot
 Mycorrhizal & rhizobial
associations
 Long lived seed bank
Historical Range
Lupinus aridorum Population Losses
Year
Number of Wild
Populations
Prior to 2002
45
2002
22
2009
8
2012
10
2014
9
Habitat loss is the primary threat to Scrub Lupine,
followed by canopy closure due to fire suppression
Why a Microhabitat Study?
Population Introductions
Year of
introduction
March 2014
total # plants
Lake Blue Scrub
2008
1,145
Mackay Gardens & Lakeside
Preserve
2010
193
Bill Frederick Park
2010
63
Tibet-Butler Preserve
2008
4
Wekiwa Springs State Park
2010
0
Oakland Nature Preserve
2011
0
Introduction location
Lake Blue Scrub
Mackay Gardens
Mackay Gardens
Bill Frederick Park – introduction site
Bill Frederick – introduction site – year 3
Microhabitat Study Goals
1. Determine whether L. aridorum has multiple
cytotypes because this can influence its spatial
distribution
2. Measure how microhabitat characteristics at locations
that support L. aridorum plants vary from random
locations within the same population
3. Measure whether microhabitat characteristics differ
between locations supporting wild or introduced
populations, to provide information about the realized
and fundamental niche.
Methodology
Populations studied:
1.
Lake McLeod (wild)
2.
Shadow Bay Park (wild)
3.
Bill Frederick Park (wild)
4.
Bill Frederick Park (introduced)
5.
Lake Blue Scrub (introduced)
6.
Mackay Gardens (introduced)
Lake McLeod
Left to right: Lois Smith, Mitch Sheets, and Jerry Burns
Shadow Bay Park
Bill Frederick Park - Old Seedbank Area
Following Site Clearing in 2010
Methodology
1. To determine the cytotypic composition
• 3 wild populations were sampled
• 10 individuals chosen from 3 microhabitats
at each site (N = 30)
• Fresh leaves collected
• Cytotyped using flow cytometry at Iowa State
University
Methodology
2. Measured microhabitat characteristics at each
population
•
•
•
•
Location = 2 meter2 quadrats
20 quadrats centered on L. aridorum plants
20 quadrats at random locations
Environmental variables were measured
Environmental variables measured:
1.
Distance to the nearest overstory tree and species id;
2.
Distance to the nearest woody shrub and species id;
3.
Soil moisture;
4.
Canopy density;
5.
Number of woody stems within the 2 m2 quadrat;
6.
Species richness within the quadrat (i.e., number of plant species);
7.
Maximum height of the understory vegetation within the quadrat;
8.
Percentage of ground cover types within the quadrat
•
Detritus (6 categories, including bare ground);
•
Grasses;
•
Herbaceous plants (non-grasses);
•
Woody plants.
Data
Statistically analyzed by
Dr. Matthew Richardson
Photo of Dr. Richardson courtesy of Photobucket
1. For wild populations, we calculated the percentage of times
four categories of overstory trees were the nearest tree to L.
aridorum plants and random quadrats: 1) P. borbonia; 2)
Pinus spp. [predominately Pinus clausa (3) Quercus spp.
(predominately Q. geminata Small); or 4) other species of
trees.
2. We calculated the percentage of times five categories of
shrubs were closest to wild and random locations: 1)
Ceratiola ericoides; 2) Garberia heterophylla; 3) Quercus spp.
(predominately Q. geminata); 4) Serenoa repens; or 5) other
species of shrubs.
3. We calculated the percentage of times four categories of
herbaceous plants were the most abundant ground cover
within the 2 m2 quadrat at wild and random locations: 1)
Cladonia leporina; 2) grass spp.; 3) Polygonella polygama; and
4) other species.
4. We calculated the percentage of times each of the
six categories of detritus was the dominant type at
wild and random locations.
 For introduced populations, calculations were
similar
• However, differences in the most prevalent
species at introduction sites, which included many
non-native species, resulted in the addition of a
non-native category
Results
1. All L. aridorum samples were diploid
2. At wild populations, the data showed that
L. aridorum plants were more likely to be located
near :
 Persea borbonia
 Serenoa repens
 Additionally, the wild quadrats were more likely
to contain a mix of detritus than in the random
quadrats
The most important predictor variables between wild
and random locations, were:
 The distance to the nearest shrub
 The proportion of bare ground
 At wild populations, L. aridorum plants were
a mean distance of 195 cm from shrubs while
random quadrats were a mean distance of 401
cm from shrubs
 In wild quadrats, 62% of the ground was bare
while in random quadrats 51% of the ground
was bare.
Moderately important predictor variables were the distance to the
nearest tree and soil moisture.
L. aridorum plants at wild populations were 37% closer to trees than
were random quadrats. Soil moisture was lower near L. aridorum
than at random quadrats.
Bill Frederick Park – wild population
3. Comparing microhabitat between introduced
populations, wild populations, and random locations,
the data highlighted a number of characteristics that
differed significantly.
 The species of the nearest tree;
 The species of the nearest shrub;
 Ground cover;
 Detritus.
Persea borbonia and Pinus species more likely to
occur near L. aridorum plants at wild populations
than at introduced populations.
Sideroxylon tenax occurred more often near L.
aridorum plants at introduced populations and near
random quadrats than near plants at wild
populations.
The ground cover plant Cladonia leporina was much
more likely to occur near wild plants than either
introduced plants or random quadrats; whereas,
Paronychia chartacea spp. chartacea and
non-native plant species were more likely found
near introduced plants and random quadrats.
In summary,
 The realized niche is narrower than the fundamental
niche.
 Community of species (trees, shrubs, groundcover)
is important.
 L. aridorum appears to grow in association with
some canopy cover and detritus, in contrast to a
number of scrub community specialists (e.g., QuintanaAscencio and Morales-Hernandez 1997; Menges et al.
2006)
Bill Frederick Park – wild population
Kerina
Kerina Parkside Tract 2 ~ Scrub Community Rescue
Thank you!
Volunteers, project partners, and funding sources:
Private landowners
Florida Native Plant Society
Ridge Rangers, Sierra Club, Master Naturalists
Florida Fish & Wildlife Conservation Commission
U.S. Fish & Wildlife Service
Florida Dept. of Agriculture and Consumer Services, DPI
The Nature Conservancy
Orange County, City of Orlando, and City of Lake Alfred