About

Cheryl Mackowiak is an Associate Professor in the Department of Soil, Water, and Ecosystem Sciences at the University of Florida, within the Institute of Food and Agricultural Sciences. Her research focuses on studying elemental cycling, specifically nitrogen, phosphorus, and carbon, in soils under perennial pasture-hay cropping systems. She emphasizes soil fertility requirements for advancing nutrient best management practices (BMPs) and develops soil nutrient management strategies aimed at improving soil and water quality. Her work also concentrates on enhancing soil's capacity to assimilate municipal and agronomic wastes. In addition to her research, Dr. Mackowiak promotes good soil stewardship through extension programs that aim to increase understanding and appreciation of soil fertility and its interaction with environmental factors affecting plant mineral nutrition. Her extension efforts are designed to support sustainable soil management practices and environmental quality.

Research topics

• Agronomy
• Biology
• Soil science
• Environmental chemistry
• Environmental science
• Chemistry

Selected publications

• Preliminary Update of Rust Disease in Florida Warm-Season Grasses

  EDIS · 2026-03-05

  articleOpen accessSenior author

  Rust is a common disease on warm-season grasses that can affect pasture health and potentially serve as an allergen for animals grazing on it. Despite its significance, rust disease in warm-season grass is often overlooked. This publication reports on rust disease observed in Florida pastures and offers practical, non-technical knowledge and general management suggestions to mitigate the threat of rust disease. It is aimed at producers, landowners, and the public.

  PublisherOA PDFDOI

• Rhizoma peanut root‐rhizome mass, growth, and decomposition under grazing or clipping management

  Crop Science · 2025-05-01 · 1 citations

  articleOpen access

  Abstract Belowground plant structures are integral to nutrient cycling in grassland ecosystems. However, relative to herbage responses, few studies have examined the belowground dynamics of warm‐season perennial forages under different management practices. This study evaluated root‐rhizome responses and decomposition dynamics of a perennial legume (rhizoma peanut [RP; Arachis glabrata Benth. ‘Ecoturf’]) under continuous stocking (Grazing) and 56‐day clipping (Haying) intervals across three 56‐day periods in 2018 and 2019. In 2019, root‐rhizome mass was greater under Haying than Grazing in two out of three periods, peaking at 14,980 kg organic matter (OM) ha −1 . Conversely, root‐rhizome N concentration was lower with Haying than Grazing (12 vs. 14 g kg −1 ). Root‐rhizome growth rate was greater in 2018 than in 2019 (18.0 vs. 10.5 kg OM ha −1 day −1 ). In 2019, Grazing exhibited greater biomass (0.0013 vs. 0.0010 g g −1 day −1 ) and N (0.0016 vs. 0.0011 g g −1 day −1 ) decay rates than Haying. Root‐rhizome N pools for 2018 and 2019 averaged 159 and 192 kg N ha −1 , with 86% and 93% N remaining post‐incubation, respectively. During a 56‐day period, N disappearance was 22.3 kg N ha −1 in 2018 and 13.4 kg N ha −1 in 2019, equating to 70 and 40 kg N ha −1 , respectively, over the 168‐day growing season. With RP covering 30% of the pasture, root‐rhizomes contribute an estimated 12–21 kg N ha −1 per season. Root‐rhizome dynamics in RP were influenced by defoliation management, though responses varied between years.

  PublisherOA PDFDOI

• Survey of Mycotoxins Present in Florida Pastures Across Time, Locations, and Grass Species

  EDIS · 2025-03-17

  articleOpen access

  The toxicity of grasses caused by mycotoxins has led to economic losses in the United States due to the health impact on livestock feeding on it. Florida's warm and humid weather is favorable for the growth of mycotoxin-producing fungi on grasses. The JECFA has provided evaluations and risk management for some high-risk mycotoxins; however, more research is needed in Florida to determine the maximum levels of these mycotoxins, how different environmental conditions affect these levels, and the specialized risk management to prevent animals from getting sick. Our Extension agents were able to collect and examine 195 grass samples from 13 ranchers across dry and wet seasons in Florida. In this publication, we summarized the results for our ranchers to learn more about (1) what (dominant) mycotoxins are generally present in Florida’s pastures, (2) what grass species could harbor more of these mycotoxins, and (3) what seasons or locations may favor these dominant mycotoxins.Accessibility Summary:In accordance with Title II regulations this content meets all points of exemption as Archived web content and/or Preexisting conventional electronic documents.

  PublisherOA PDFDOI

• Optimizing nitrogen fertilizer recommendations for field corn grown in Florida sandy soils

  Agronomy Journal · 2025-09-01 · 1 citations

  articleOpen access

  Abstract Nitrogen (N) is essential to maximize corn ( Zea mays L.) yield; however, over‐ and underapplication can cause environmental concerns or yield losses. Optimizing N management is critical to balance productivity and sustainability. This study was conducted during 2022–2024 in Florida to determine corn N response. The experiment included six N rates (0–392 kg N ha −1 by 78.5 increments) over 3 years, with an additional rate (471 kg N ha −1 ) in the third year, using a randomized complete block design with four replications. Results showed that 314–471 kg N ha −1 produced the highest and statistically similar aboveground biomass (21,598–23,166 kg ha −1 ), grain yield (12,479–13,588 kg ha −1 ), and N uptake (227–250 kg ha −1 ). For grain N removal, (144–162 kg ha −1 ), 392 and 471 kg N ha −1 were statistically similar, while 314 kg N ha −1 was significantly lower than 392 kg N ha −1 , indicating a threshold response beyond 314 kg N ha −1 . Agronomic N use efficiency and partial factor productivity were highest at 157 (58.8 kg kg −1 ) and 78.5 (57.9 kg kg −1 ) kg N ha −1 , respectively. Results suggest no agronomic advantage above the 314 kg N ha −1 rate, and yield decreased at 471 kg N ha −1 . Response analysis indicated that 23.2 g N was required per kg of corn grain under irrigation system. The nitrogen nutrition index confirmed that moderate applications (235–314 kg N ha −1 ) sustained crop N status, while higher rates (>392 kg N ha −1 ) offered little to no benefit. Collectively, these results support refining N recommendations to optimize agronomic production in Florida.

  PublisherDOI

• Nutrient Management in Low-Chill Peach Orchards: Guidelines for Deficiency Symptoms and Leaf and Soil Sampling

  EDIS · 2025-09-17

  articleOpen access

  Timely and informed fertilization practices in peach production are essential to obtain high yields, optimal fruit quality, and secure long-term orchard health and productivity. Recognizing nutrient deficiency symptoms can help identify which nutrients a plant may be lacking, but a solid nutrient management program should regularly test soil and foliar samples to detect issues before symptoms appear. This publication provides suggested nutrient sufficiency ranges for peach trees, along with practical guidelines for identifying nutrient deficiency symptoms and conducting soil and foliar sampling in the orchard. Its goal is to support county Extension agents and faculty, growers, and homeowners with general and practical guidelines for optimizing nutrient management in peach orchards.

  PublisherOA PDFDOI

• Life cycle assessment of contrasting grazing systems within a yearling stocker stage of beef cattle production

  Journal of Agriculture and Food Research · 2025-09-23 · 1 citations

  articleOpen access

  Life cycle assessment (LCA) was used to compare the environmental impacts of three grazing systems for beef cattle backgrounding in North Florida. The systems were grass + clover (GL), grass + clover + rhizoma peanut (GLRP), and grass + nitrogen fertilizer (GN). Our hypothesis was that incorporating legumes into grazing systems decreases reliance on fossil fuels and inorganic fertilizers and reduces the environmental impact of beef production systems. The LCA assessed five environmental impact categories: global warming potential, freshwater eutrophication, marine eutrophication, fossil fuel scarcity, and acidification potential. A cradle-to-farm gate system boundary encompassed the processes within the backgrounding stage. The functional unit adopted was 1 kg of liveweight gain. Results indicated that the GN system had the greatest environmental impacts, driven primarily by elevated nitrous oxide (N 2 O) emissions from synthetic N fertilizer use and methane (CH 4 ) emissions from enteric fermentation, along with greater fossil fuel consumption associated with fertilizer production and application. In contrast, GLRP impacted the environment less across all categories. This was attributed to legume biological N fixation, which reduced the need for synthetic fertilizers and, consequently, decreased greenhouse gas emissions, eutrophication potential, and acidification. This study highlights the potential of legume integration into grazing systems, particularly GLRP, as an alternative to N-fertilized grass systems. By reducing reliance on synthetic fertilizers and mitigating environmental impacts, GLRP enhanced the sustainability of beef production in North Florida. These findings document the value of legumes for improving the environmental performance of livestock systems, particularly as global demand for sustainable food production intensifies. • Life cycle assessment compared legume-integrated and nitrogen-fertilized grazing systems for beef cattle. • Legume-based systems reduced environmental impacts across all categories, especially greenhouse gas emissions and nutrient runoff. • Conventional grass-nitrogen systems had higher emissions and fossil fuel use due to synthetic fertilizer dependence. • Results support legume integration as a strategy for sustainable beef production in the southeastern U.S.

  PublisherDOI

• Sward responses of rhizoma peanut–bahiagrass mixtures and bahiagrass monocultures in contrasting on‐farm environments

  Crop Science · 2025-03-01 · 1 citations

  articleOpen access

  Abstract Incorporating forage legumes into grass swards has the potential to enhance the sustainability of pasture systems and reduce reliance on nitrogen fertilizers. The aim of this study was to assess the on‐farm performance of bahiagrass (BG; Paspalum notatum Flüggé)–rhizoma peanut (RP; Arachis glabrata Benth.) mixtures compared to BG monocultures in three diverse environments across Florida. Three forage treatments were employed at all locations: BG in monoculture (Bh), BG + Ecoturf RP (Eco), and BG + Florigraze RP (Flo). Significantly greater herbage accumulation rates were observed for BG + Ecoturf RP (37 kg DM ha −1 day −1 , where DM is the dry matter) and BG with Florigraze RP (35 kg DM ha −1 day −1 ) in comparison with BG in monoculture (30 kg DM ha −1 day −1 ). Crude protein and in vitro digestible organic matter concentrations were greater for RP binary mixtures compared with monoculture BG across all locations. In North and South Florida, BG + Ecoturf RP exhibited greater RP belowground biomass than BG + Florigraze RP. Additionally, biological N 2 fixation increased linearly as the proportion of RP increased. Integration of RP germplasm Ecoturf and the Florigraze cultivar into BG pastures in North, Central, and South Florida led to increased rates of herbage accumulation and improved herbage nutritive value compared to BG monoculture. Overall, North and South Florida exhibited more favorable responses to the inclusion of RP compared to Central Florida.

  PublisherOA PDFDOI

• A novel technique utilizing enriched 15N2 to trace nitrogen transfer in grass and legume mixtures

  Scientific Reports · 2025-07-08

  articleOpen access

  Legumes are a potentially important N source in pasture systems, but quantifying the transfer of biologically fixed N from the legume to the grass component is difficult. A greenhouse H-pot system was developed to directly estimate belowground N transfer from biological N2 fixation (BNF) using 15N2. The system was tested with ‘Prine’ annual ryegrass (Lolium multiflorum L.) and ‘Dixie’ crimson clover (Trifolium incarnatum L.). Legume and grass root systems growing in either individual or H pots were exposed to 15N2. Control H pots were separated by mesh to prevent contact between roots from each side of the pot. To reduce enriched gas volume demand and avoid cross-contamination in the greenhouse, the gas was supplied through underground tubes in the root zone. Ryegrass and clover exhibited an enrichment of 15N2 when their respective root systems were supplied with 15N2. Additionally, ryegrass also showed enrichment when clover roots received the gas, provided there was direct contact between the root systems on both sides of the H pot; however, this enrichment did not occur when such contact was prevented. Plants cultivated in monoculture without the application of 15N2 did not present enrichment. The H-pot facilitates the evaluation of belowground transmission, an essential mechanism for N transfer. The technique of gradually supplying 15N2 directly to the root system may serve as a valuable labeling method for tracking nitrogen transfer. The absence of enrichment when plants were not directly supplied indicates negligible atmospheric enrichment. However, the enrichment observed in ryegrass when supplied with the gas suggests BNF through alternative pathways.

  PublisherOA PDFDOI

• Nutrient Management in Low-Chill Peach Orchards: Guidelines for Fertilizer Rate Application in Florida Subtropical Climate

  EDIS · 2025-09-17

  articleOpen access

  Appropriate fertilization of perennial fruit tree species is critical to ensure vegetative and reproductive growth, as these processes demand considerable amounts of resources. Adequate fertilization management practices at all stages of peach development are essential to obtain high yields and optimal fruit quality, as well as to ensure healthy vegetative growth that supports the crop for the following year. Fertilization practices are also important economically since they represent an important portion of the costs associated with peach production. Improper fertilization can have negative agronomic and environmental consequences. This publication discusses and suggests general fertilization management practices for peach trees growing under the subtropical climate of Florida to provide information to county and state Extension faculty, growers, and homeowners interested in peach production in Florida.

  PublisherOA PDFDOI

• Note on the nesting biology of <i>Epimelissodes aegis</i> LaBerge (Hymenoptera: Apidae)

  Florida Entomologist · 2025-01-01

  articleOpen access

  Abstract A nesting site of Epimelissodes aegis (LaBerge) (Hymenoptera: Apidae: Eucerini) was discovered in late September 2023 at the University of Florida North Florida Research and Extension Center in Quincy, Florida. At least 20 nests were active in a single eight-row cotton plot of a managed nitrogen rate and fungicide trial. Other than floral host records, the nesting behavior of this species is relatively understudied, considering its broad range across the Gulf and Atlantic coasts in the Southeastern United States. The nesting behavior of E. aegis appears to be similar to that of other published accounts within the genus. Although from our findings we cannot conclude whether E. aegis nests communally or solitarily. Additionally, the parasite Triepeolus concavus (Cresson) (Hymenoptera: Apidae: Epeolini) was observed resting nearby nest entrances, walking around entrances, occasionally peeking in, entering briefly before exiting, and sometimes disappearing into the nest entrance for longer periods of time. T. concavus also has been reported from nests of Epimelissodes obliqua (Say), but a collection from nests of E. aegis is a novel host association. This note provides new information on the nesting behavior of E. aegis, which is relatively understudied.

  PublisherOA PDFDOI

Frequent coauthors

• Ann R. Blount

  Southwest Florida Research

  84 shared

• Raymond M. Wheeler

  Kennedy Space Center

  73 shared

• José Carlos Batista Dubeux

  University of Florida

  64 shared

• John C. Sager

  62 shared

• N.C. Yorio

  Kennedy Space Center

  50 shared

• W. M. Knott

  Kennedy Space Center

  39 shared

• Gary W. Stutte

  35 shared

• Erick R. S. Santos

  University of Alberta

  31 shared

Education

• PhD, Plants, Soils, and Climate

  Utah State University

  2001