Florida Landscape Research Articles

Rancher Perceptions of the Coyote in Florida

Throughout the continental United States and large portions of Canada and Central America, changes people make to the landscape such as the clearing of forested land and the extermination of larger predators like gray and red wolves have made the environment perfect for the adaptive coyote. Coyotes have rapidly taken advantage of these environmental shifts and expanded into new areas, now including all 67 counties in Florida and even Key Largo. Each year more people in Florida catch a glimpse of a coyote crossing a road or running across open fields, or notice coyote scat along a hiking trail–and farmers and ranchers are seeing signs of coyotes on their farms. As coyotes become a fixture of the Florida landscape, potential grows for conflict with humans. Coyotes are in Florida to stay, and understanding the agricultural community’s perception of their influence on livestock and wildlife is important to developing effective policies for coyote management. This revised 4-page fact sheet provides results of ongoing statewide surveys of ranchers in Florida regarding the influence of coyotes on their operations. Written by Raoul K. Boughton, Bethany Wight, and Martin B. Main, and published by the Wildlife Ecology and Conservation Department, January 2016. WEC 146/UW143: Rancher Perceptions of the Coyote in Florida (ufl.edu)

Importance of ET Controller Program Settings on Water Conservation Potential

In unincorporated Orange County, Florida, 57% to 62% of single-family residential homes were found to regularly over-irrigate, resulting in the need to find better ways to schedule automatic irrigation. The objective of this research was to evaluate the effects of programming for identical virtual landscapes to further explore the water savings potential of evapotranspiration (ET) controllers. As a virtual test, three Rain Bird ET controllers were studied: the ESP-SMT controller with two firmware options (original and an updated), and the ESP-SMTe, a replacement product for the ESP-SMT. Irrigation was scheduled for a virtual central Florida landscape by altering possible program settings of plant type, microclimate, soil type, and density that relate directly to parameters used in the soil water balance. The ESP-SMTe consistently applied similar amounts of irrigation to the ESP-SMT with updated firmware, indicating that controller updates were minor between the two models. The settings were optimized for Florida landscapes by selecting a heavier soil type, increasing the shade, and selecting a medium stand for a custom plant type, resulting in reductions in irrigation application. The ESP-SMTe and ESP-SMT with updated firmware were different from the ESP-SMT with original firmware, where newer models applied more water despite identical settings, averaging 12 to 21 mm more per month than the original firmware. Additionally, all of the controllers were unable to fully account for rainfall throughout the test resulting in a minimum of 51% in over-irrigation compared to the gross irrigation requirement (GIR). Increasing the accuracy of rainfall accounting would be extremely beneficial to overall water conservation and efficiency. In a separate, independent ET controller study, there was a large discrepancy in irrigation application among multiple brands programmed to irrigate the same virtual landscape. This further shows the importance of understanding the algorithms behind the program settings.

Host Plants and Natural Enemies of Rugose Spiraling Whitefly (Hemiptera: Aleyrodidae) in Florida

The rugose spiraling whitefly, Aleurodicus rugioperculatus Martin (Hemiptera: Aleyrodidae), is a polyphagous pest that has caused significant damage in the Florida landscape. Various plants have been identified as primary hosts in affected areas. Rugose spiraling whitefly was confirmed in 22 counties, and surveys for biological control agents have found several important natural enemies and other species that collectively provide appreciable control of this whitefly pest.

Insecticide Trial for Cycad Aulacaspis Scale on Sago Palm, 2014: Table 1

The cycad aulacaspis scale (CAS) is a significant invasive pest on cycads, especially among the genera Cycas . Damage by CAS, an armored scale insect, has resulted in the removal of millions of cycads from Florida landscapes. The objective of this study was to assess efficacy of biological and botanical insecticides for control of CAS relative to that of insecticidal standard. The trial was conducted at the University of Florida Research and Education Center in Apopka, Florida, on 3-yr-old sago palms potted in 7-gal containers. A total of 25 naturally …

Nutrient enrichment intensifies hurricane impact in scrub mangrove ecosystems in the Indian River Lagoon, Florida, USA.

Mangroves are an ecological assemblage of trees and shrubs adapted to grow in intertidal environments along tropical, subtropical, and warm temperate coasts. Despite repeated demonstrations of their ecologic and economic value, multiple stressors including nutrient over-enrichment threaten these and other coastal wetlands globally. These ecosystems will be further stressed if tropical storm intensity and frequency increase in response to global climate changes. These stressors will likely interact, but the outcome of that interaction is uncertain. Here, we examined potential interaction between nutrient over-enrichment and the September 2004 hurricanes. Hurricanes Frances and Jeanne made landfall along Florida's Indian River Lagoon and caused extensive damage to a long-term fertilization experiment in a mangrove forest, which previously revealed that productivity was nitrogen (N) limited across the forest and, in particular, that N enrichment dramatically increased growth rates and aboveground biomass of stunted Avicennia germinans trees in the interior scrub zone. During the hurricanes, these trees experienced significant defoliation with three to four times greater reduction in leaf area index (LAI) than control trees. Over the long-term, the +N scrub trees took four years to recover compared to two years for controls. In the adjacent fringe and transition zones, LAI was reduced by > 70%, but with no differences based on zone or fertilization treatment. Despite continued delayed mortality for at least five years after the storms, LAI in the fringe and transition returned to pre-hurricane conditions in two years. Thus, nutrient over-enrichment of the coastal zone will increase the productivity of scrub mangroves, which dominate much of the mangrove landscape in Florida and the Caribbean; however, that benefit is offset by a decrease in their resistance and resilience to hurricane damage that has the potential to destabilize the system.

Resource selection reflects fitness associations for an endangered bird in restored habitat

Conservation practitioners frequently have limited information on the structure and function of the ecosystems they wish to preserve, and as a result, they may use shortcuts to guide conservation actions. One such shortcut is the umbrella species approach, whereby conservation actions are geared toward one or a few key species, with the assumption that the entire community will benefit. However, fitness–habitat associations and resource use may vary across space and across management regimes, and so too may the utility of umbrella species as ecosystem surrogates. The federally endangered red-cockaded woodpecker (Picoides borealis) has been used as an umbrella species in the restoration of the longleaf pine ecosystem of the southeastern US. Restoration efforts were based on early habitat selection information in largely degraded landscapes. We examined patterns of resource selection of 97 social groups of red-cockaded woodpeckers in a restored landscape in northwest Florida. Similar to previous studies in degraded landscapes, woodpecker groups selected forest stands containing higher densities of large pines and lower densities of small pines for foraging. However, we found no evidence for another aspect of habitat selection widely documented in degraded habitat, the avoidance of areas with substantial components of hardwoods. These results align with new woodpecker fitness–habitat associations within restored landscapes and lend support to previous findings that current ecosystem restoration efforts in the study area, namely prescribed burning, may have reduced hardwood densities to below those at which they have negative impacts. The red-cockaded woodpecker has served as an effective umbrella species in degraded longleaf ecosystems by promoting management, especially prescribed burning, that benefits many other species. Whether it will continue to do so in restored habitat is not yet clear, but its tolerance of a range of hardwood conditions provides reason for optimism.

Not All Landscape Palm Fertilizers Are Created Equal

Palms are widely planted in Florida landscapes. Their bold leaf textures create a tropical or Mediterranean look that is highly desired by residents and tourists alike. But palms have very high nutritional requirements, and deficiencies of any element can result in conspicuous and unattractive symptoms on their large leaves. UF/IFAS research shows that the most effective fertilizer has 100% of the N, K, Mg, and B sources in slow-release or controlled-release form and that all of the Mn, Fe, Zn, and Cu sources should be water soluble. This 4-page fact sheet explains the reasons for this recommendation and how to ensure that you have a formulation that will be effective. Written by Timothy K. Broschat, and published by the UF Department of Environmental Horticulture, April 2015. (Photo Credit: T.K. Broschat) ENH1255/EP516: Not All Landscape Palm Fertilizers Are Created Equal (ufl.edu)

Operational Actual Wetland Evapotranspiration Estimation for South Florida Using MODIS Imagery

Evapotranspiration is a reliable indicator of wetland health. Wetlands are an important and valuable ecosystem on the South Florida landscape. Accurate wetland Actual Evapotranspiration (AET) data can be used to evaluate the performance of South Florida’s Everglades restoration programs. However, reliable AET measurements rely on scattered point measurements restricting applications over a larger area. The objective of this study was to validate the ability of the Simplified Surface Energy Balance (SSEB) approach and the Simple Method (also called the Abtew Method) to provide large area AET estimates for wetland recovery efforts. The study used Moderate Resolution Imaging Spectroradiometer (MODIS) sensor spectral data and South Florida Water Management District (SFWMD) solar radiation data to derive weekly AET values for South Florida. The SSEB-Simple Method approach provided acceptable results with good agreement with observed values during the critical dry season period, when cloud cover was low (rave (n = 59) = 0.700, pave < 0.0005), but requires further refinement to be viable for yearly estimates because of poor performance during wet season months, mainly because of cloud contamination. The approach can be useful for short-term wetland recovery assessment projects that occur during the dry season and/or long term projects that compare site AET rates from dry season to dry season.

Using Social Marketing Principles to Understand an Extension Audience’s Landscape Water Conservation Practices

A substantial amount of water is applied to Florida landscapes, and encouraging water conservation through irrigation practices has been identified as a priority programming area where there is great opportunity to positively affect the state’s water resources. Florida Extension addresses this priority area through educational programming. Social marketing has been identified as a promising approach to changing behaviors that influence environmental issues, such as water-saving irrigation technologies and practices. This approach recognizes that there are barriers that prevent individuals from engaging in positive behavior changes. This study evaluated an irrigation seminar using a retrospective pretest-posttest design that incorporated elements of a social marketing intercept survey. Thirty-four attendees participated and primarily represented green industry professional and government sectors. Study objectives were to evaluate the workshop and describe the audience using social marketing principles for future program planning based on audience research. The audience rated their descriptive norms, a strong predictor of behavioral change, lower than their injunctive norms, a less robust predictor. The majority planned to adopt at least one water-conservation best management practice as a result of the workshop. We make recommendations for applying social marketing principles to Extension programming.

The influence of disturbed habitat on the spatial ecology of Argentine black and white tegu (Tupinambis merianae), a recent invader in the Everglades ecosystem (Florida, USA)

The threat of invasive species is often intensified in disturbed habitat. To optimize control programs, it is necessary to understand how degraded habitat influences the behavior of invasive species. We conducted a radio telemetry study to characterize movement and habitat use of introduced male Argentine black and white tegus (Tupinambis merianae) in the Everglades of southern Florida from May to August 2012 at the core and periphery of the introduced range. Tegus at the periphery moved farther per day (mean 131.7 ± 11.6 m, n = 6) compared to tegus at the core (mean 50.3 ± 12.4 m, n = 6). However, activity ranges were not significantly smaller in the core (mean 19.4 ± 8.4 ha, n = 6) compared to periphery (mean 29.1 ± 5.2 ha, n = 6). Peripheral activity ranges were more linear due to activity being largely restricted to levee habitat surrounded by open water or marsh. Tegus were located in shrub or tree habitat (mean 96 %) more often than expected based on random locations (mean 58 %), and the percent cover of trees and shrubs was higher in activity ranges (mean 61 %) than the general study area (17 %). Our study highlighted the ability of tegus to spread across the Florida landscape, especially in linear disturbed habitats where increased movement occurred and in areas of altered hydrology where movement is not restricted by water.

The application of oyster and seagrass models to evaluate alternative inflow scenarios related to Everglades restoration

The South Florida landscape is highly engineered featuring ∼3380km of canals, ∼1225 water control structures, >70 pumping stations, managed wetlands, densely populated coastal watersheds, and impacted estuaries. Landscape scale agricultural and urban modifications require flood control which sometimes results in the release of excess freshwater that potentially damages estuarine ecology. The Central Everglades Planning Project (CEPP) is a partnership between the U.S. Army Corps of Engineers and the South Florida Water Management District focused on restoring natural patterns of freshwater flow to the Everglades and associated estuaries. One of the primary project goals is to reduce deleterious inflows eastward to the St. Lucie Estuary (SLE) and westward to the Caloosahatchee River Estuary (CRE) by diverting freshwater south from Lake Okeechobee. Performance evaluation of the CEPP relies upon integrated modeling which links the watershed engineering projects to estuarine salinities and biotic responses. The objective of this study was to utilize seagrass and oyster models to evaluate the effectiveness of alternative inflow scenarios. There are three different scenarios: the existing condition base (ECB), the future without proposed CEPP projects (FWO) but with other landscape features that could alter freshwater inflows, and alternative 4R (ALT4R) that incorporates a suite of restoration projects including those associated with the CEPP. Each of these inflow scenarios was used to generate daily salinity time series from 1965 to 2005 at multiple locations in the SLE and CRE which were used to run site-specific seagrass and oyster models. The hydrodynamic and ecological effects of freshwater inflow were greater in the SLE compared to the much larger CRE. Predicted densities of oysters (individualsm−2) and seagrass (shootsm−2) were greater in the wet season (May–Oct) vs. the dry season (Nov–Apr) in both estuaries. Oyster and seagrass densities increased under the ALT4R inflow scenario that mitigated high inflows to the estuaries in the wet season. This result improved environmental conditions while increasing freshwater availability for other parts of the Greater Everglades and the southern estuaries such as Florida Bay and Biscayne Bay.

Effect of Nitrogen Fertilization Rate on Aesthetic Quality of Landscape-grown Vines and Groundcovers

Research supporting recommendations for fertilizer needs of landscape-grown vines and groundcovers is lacking. The objectives of our study were to (1) evaluate the quality response of selected vine and groundcover species to nitrogen (N) fertilization at five rates and (2) validate the recommended N fertilizer rates (from the initial evaluation) by monitoring quality of additional landscape-grown vine and groundcover species. Three vine species and two groundcover species were planted in west-central Florida into raised beds containing subsoil fill material in a completely randomized design. Plants were fertilized every 6 weeks with a controlled release fertilizer (20N–0P–0K–23S) at an annual N rate of 0, 2, 4, 6, or 12 lb/1000 ft2. Plant aesthetic quality (0–5 scale) was assessed every 6 weeks for 30 weeks after planting. Although quality of some species increased significantly as N rate increased, all plants supplied with at least 4 lb/1000 ft2 per year N fertilizer had acceptable quality ratings of 3 or better. Screening of three additional vines and four additional groundcovers fertilized with controlled release fertilizer (42N–0P–0K) at an annual N rate of 3, 5, or 7 lb/1000 ft2 confirmed that fertilization with 2 to 4 lb/1000 ft2 per year should be adequate to maintain acceptable vines and groundcovers grown in the landscape in west-central Florida.

Bitten: My Unexpected Love Affair with Florida

While we environmental writers make much of our intimate relationships to our home places, we are often transplants from some other place—a fact that sometimes remains hidden beneath the ennobling rhetoric of rootedness that is characteristic of our genre. Perhaps no American state so thoroughly reflects our condition of mobility and transience as does Florida, a vast and beautiful landscape that has been radically transformed from wilderness to condos in the short half century since air conditioning became a staple of the American home. Among the many strengths of Andrew Furman's approach to his inhabitory practice in southeastern Florida is his candid admission that he himself is a non-native transplant—yet another of the invasive exotics that have profoundly transformed the ecosystems of the Sunshine State. In Bitten, Furman must reckon what to make of a diminished thing. He is painfully aware that his adoptive home state is often perceived as a wasteland of golf courses and gated communities that has replaced habitats of stunning biodiversity, and so he seeks ways to register this loss while still engaging fully with the beauty that remains. He soon finds that what endures is in fact spectacular, and so his discoveries challenge uninformed dismissals of Florida as environmentally irredeemable. Because he is a birdwatcher, fisherman, amateur botanist, and native plant gardener, Furman's interests take us into a number of Florida landscapes and introduce us to a variety of plant and animal species. Among my favorite chapters is the one in which he describes night fishing just off the Florida coast, an experience that allows him to look back at coastal development while at the same time experiencing visceral contact with ocean and night.

Natural Products for Managing Landscape and Garden Pests in Florida

This publication describes “natural” pesticides: alternatives that are usually less toxic to non-target organisms and the environment and that, when used correctly, can be effective substitutes for synthetic products. In this publication, natural substances used for pest management in landscapes and gardens are grouped into oils, plant extracts, insecticidal soaps, mineral insecticides, microbial insecticides, and products that control diseases. Certain products contain combinations of these groups (e.g., soap and oil). This revised 8-page fact sheet was written by Eileen A. Buss and Sydney G. Park Brown, and published by the UF Department of Entomology and Nematology, June 2014. ENY-350/IN197: Natural Products for Managing Landscape and Garden Pests in Florida (ufl.edu)

Nematode Management for Bedding Plants

Florida is the “land of flowers.” Surely, one of the things that Florida is known for is the beauty of its vegetation. Due to the tropical and subtropical environment, color can abound in Florida landscapes year-round. Unfortunately, plants are not the only organisms that enjoy the mild climate. Due to warm temperatures, sandy soil, and humidity, Florida has more than its fair share of pests and pathogens that attack bedding plants. Plant-parasitic nematodes can be among the most damaging and hard-to-control of these organisms. This revised 11-page fact sheet was written by William T. Crow and published by the UF Department of Entomology and Nematology, February 2014.
 ENY-052/IN470: Nematode Management for Bedding Plants (ufl.edu)

Alternatives to Invasive Plants Commonly Found in South Florida Landscapes

Based on years of UF/IFAS research producing and trialing cultivars, this 5-page fact sheet lists native and non-invasive, non-native ornamentals as alternatives to invasive plants commonly used in Florida landscapes. Only plants considered to be generally available in the nursery trade are listed. Alternative plants are similar to respective invasive plants as much as possible in terms of size, habit, texture, and flower color. Written by Gary W. Knox, Sandra B. Wilson, Zhanao Deng, and Rosanna Freyre, and published by the UF Department of Environmental Horticulture, September 2013. http://edis.ifas.ufl.edu/ep483

Spanish Moss, Ball Moss, and Lichens - Harmless Epiphytes

Epiphytes are “air” plants that survive on moisture and nutrients in the atmosphere. Several epiphytic plants, like Spanish moss, ball moss, and lichen, are common to the Florida landscape and southeast United States. People unfamiliar with epiphytes sometimes worry that they may cause injuries to the plants they perch in. Epiphytes do attach themselves to plants, but they do not harm the plants, unlike mistletoe, a plant parasite. Without soil as a source of nutrients, epiphytic plants have evolved the capacity to obtain minerals dissolved in water that flows across leaves and down branches. This 3-page fact sheet was written by Joe Sewards and Sydney Park Brown, and published by the UF Department of Environmental Horticulture, September 2013. http://edis.ifas.ufl.edu/ep485

Natural Enemies of Rugose Spiraling Whitefly, Aleurodicus rugioperculatus Martin (Insecta: Hemiptera: Aleyrodidae) in the South Florida Landscape

Rugose spiraling whitefly was first observed in south Florida in 2009. It has been found in 17 counties in south and central Florida. This whitefly has been reported on more than 60 plant species, which include gumbo limbo, coconut, black olive, avocado, Calophyllum spp., and giant white bird of paradise. This 6-page fact sheet describes the predators and parasitoids found feeding on this whitefly in the south Florida landscape. Written by Siavash Taravati, Catharine Mannion and Holly Glenn, and published by the UF Department of Entomology and Nematology, August 2013.
 http://edis.ifas.ufl.edu/in1004

How to Minimize Wind Damage in the South Florida Landscape

When an area has been free of hurricane-strength winds for a number of years, there is a possibility of severe damage to trees and to the structures near them when a storm finally hits. Trees and shrubs, even those native to an area, can grow too massive or unbalanced to be able to stand windstorms. This document explains how to prune and shape trees in order to minimize the risks of damage. First published in Sept. 1985.

Phylogeography of Aedes aegypti (Yellow Fever Mosquito) in South Florida: mtDNA Evidence for Human-Aided Dispersal

The invasive dengue vector Aedes aegypti has persisted for > 200 years in South Florida in the United States. We tested the hypotheses that Florida's landscape creates dispersal barriers and corridors and that long-distance human-aided dispersal structures populations of Ae. aegypti. We evaluated the phylogeography of 362 individuals from Florida's East and West Coasts with a 760-bp (418- and 342-bp fragments of ND5 and ND4, respectively) mitochondrial sequence. Populations from these two coasts were not significantly differentiated, suggesting that limited urbanization in central Florida is not a strong barrier to gene flow. Evidence for long-distance dispersal between Ft. Lauderdale and the West and Ft. Myers and the East indicates the importance of human-aided dispersal. West Coast populations showed no genetic differentiation, indicating that West Coast rivers and bays did not significantly impede gene flow. Phylogeographic analysis of haplotypes showed two distinct matrilines with no geographic patterns, suggesting multiple introductions or balancing selection.