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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Superação de dormência e produção de mudas de Anacauíta (Schinus molle L.) / Overcome dormancy and seedlings production of anacauita (Schinus molle L.)

Leal, Cintia Müller 07 December 2015 (has links)
Submitted by Maria Beatriz Vieira (mbeatriz.vieira@gmail.com) on 2017-04-04T13:22:16Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_cintia_muller_leal.pdf: 2650724 bytes, checksum: 0735a2bb9f056999c0b6a14b82b893b4 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-04-07T18:52:23Z (GMT) No. of bitstreams: 2 dissertacao_cintia_muller_leal.pdf: 2650724 bytes, checksum: 0735a2bb9f056999c0b6a14b82b893b4 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-04-07T18:59:09Z (GMT) No. of bitstreams: 2 dissertacao_cintia_muller_leal.pdf: 2650724 bytes, checksum: 0735a2bb9f056999c0b6a14b82b893b4 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-04-07T18:59:23Z (GMT). No. of bitstreams: 2 dissertacao_cintia_muller_leal.pdf: 2650724 bytes, checksum: 0735a2bb9f056999c0b6a14b82b893b4 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015-12-07 / Sem bolsa / Anacauíta (Schinus molle L.) é uma espécie arbórea de ocorrência nativa no Rio Grande do Sul, pioneira de pequeno porte, com importância ecológica, bioquímica e farmacológica, contudo suas sementes apresentam dormência, fato que dificulta a produção de mudas em escala comercial. Este trabalho objetivou avaliar métodos de superação de dormência das sementes de S. molle de um lote com 15 meses de armazenamento em câmara fria seca e germinação inicial de 5% quando submetidas a tratamento para superação de dormência com ácido sulfúrico por 160 minutos, utilizando diferentes tempos de escarificação mecânica (150, 300, 450 e 600 segundos) em escarificador elétrico equipado com lixa grão 80. O tratamento de 150 segundos de escarificação mecânica proporcionou maior percentual de germinação (61%), menor número de sementes mortas e plântulas anormais, maior massa seca e comprimento de plântulas aos sete dias, maior embebição e maior índice de velocidade de emergência (2,28). Para a produção de mudas desta espécie foram testados dois volumes de tubetes (100 e 175 mL) e quatro níveis de adubação com fertilizante de liberação controlada (FLC) Osmocote Plus, em um experimento fatorial 2 x 4. Os níveis de adubação com FLC foram zero, quatro, oito e doze gramas por litro de substrato. Os resultados quanto aos parâmetros de crescimento e qualidade de mudas, onde foram avaliados altura, diâmetro do coleto, número de folhas, relação altura/diâmetro do coleto, massa seca da raiz, massa seca da parte aérea, massa seca total, relação massa seca da parte aérea e massa seca da raiz, volume de raiz, índice de qualidade de Dickson, índice de clorofila, teor de clorofila a, clorofila b e carotenoides ao longo de 120 dias após a emergência das plântulas, revelou que o tubete de 175 mL e a dosagem de oito gramas de FLC por litro de substrato foi superior aos demais tratamentos por produzir mudas de anacauíta de alta qualidade. / Anacauita (Schinus molle L.) is arborea, native species in a Rio Grande do Sul small pioneer with ecological, biochemical and pharmacological importance, but its seeds present dormancy , a fact that hinders the production of seedlings on a commercial scale. This study aimed at evaluating methods of overcoming seed dormancy of S. molle of a batch of 15 months of storage in dry cold chamber and 5% germination when undergoing treatment to overcome dormancy with sulfuric acid for 160 minutes, using different times mechanical scarification (150, 300, 450 and 600 seconds) in electric scarifier equipped with 80 grit sandpaper. Treatment of 150 seconds of mechanical scarification showed higher germination percentage (61%), fewer dead seeds and abnormal seedlings, imbibition largest and most emergency velocity index (2.28). For the production of seedlings of this species were tested two volumes of tubes (100 and 175 mL) and four levels of fertilizer controlled release fertilizer (CRF) Osmocote Plus in 2 x 4 factorial experiment. Nutrient levels were CRF zero, four, eight and twelve grams per liter of substrate. The results regarding the growth parameters and quality seedlings, which were assessed height, stem diameter, number of leaves, height / stem diameter, root dry mass, dry mass of shoots, total dry matter, dry weight ratio of shoot and root dry mass, root volume, Dickson quality index, chlorophyll index, chlorophyll content a, chlorophyll b and carotenoids over 120 days after seedling emergence, revealed that the plastic tube 175 ml and the dose of CRF eight grams per liter substrate was superior to the other treatments for producing seedlings of high quality anacauita.
12

Eficiência da adubação com misturas de ureia comercial e ureia recoberta com enxofre e polímero na semeadura do milho / Efficiency of fertilization at corn sowing with blends of urea and polymer sulfur coated urea

Pedro Lopes Garcia 06 February 2017 (has links)
Misturas de ureia (U) e ureia revestida com enxofre e polímero (URP) podem ser uma alternativa para melhorar a eficiência de utilização de nitrogênio (EUN) e reduzir custos quando aplicadas de uma única vez em cultivos agrícolas. Em experimentos de campo foram investigados diferentes índices de EUN (eficiência de recuperação aparente (ERA), eficiêncica fisiológica (EF), eficiência de utilização interna (EUI), eficiência agronômica (EA) e fator parcial (FPP) do N aplicado) e o acúmulo e particionamento de macronutrientes no milho (Zea mays L.) com misturas de U e URP na dose de 180 kg ha-1 aplicados totalmente na semeadura em Latossolo Vermelho Amarelo distrófico (LVAd) e Latossolo Vermelho distrófico (LVd). Foi incluído tratamento com ureia em manejo convencional (UMC). As misturas de URP+U foram incorporadas em faixa, 5 cm abaixo e 10 cm ao lado da linha de semeadura. As plantas foram amostradas em quatro estádios e divididas em quatro frações da planta (partes da planta) para a determinação de nutrientes. No LVAd, tratamentos com 100%URP, 70%URP+30%U e 60%URP+40%U apresentaram maior produtividade que o tratamento controle; 100%U e UMC tiveram menor EF e EUI que o 100%URP; todos os tratamentos com N apresentaram maior acúmulo total de N e massa seca que o controle em R6; a proporção de 70%URP+30%U apresentou maior acúmulo de S total do que o controle e UMC em R6. Não foram verificadas diferenças entre os tratamentos para produtividade, índices de EUN e acúmulo total de nutrientes no LVd. Em experimentos em casa de vegetação foram avaliados a condutividade elétrica (CE) e o pH do solo, altura, diâmetro, massa seca e acúmulo de N no desenvolvimento inicial de plantas de milho usando a mistura de 70%URP+30%U aplicada em faixa na semeadura do milho, das seguintes maneiras: 1) aplicando-se uma dose equivalente a 180 kg ha-1 de N em diferentes posições (5, 10 e 15 cm abaixo e 0, 5 e 10 cm ao lado da linha de semeadura) em um Latossolo Vermelho eutrófico (LVe) e comparando com 100%U; 2) variando as doses de N (equivalente a 0, 90, 180, 360 e 540 kg ha-1 de N) em uma posição considerada adequada (15 cm abaixo e 10 cm ao lado da linha de semeadura) no LVe e no LVAd. As aplicações feitas 15 cm abaixo da linha de semeadura apresentaram maior CE na linha do fertilizante na camada 9-18cm, pH na linha do fertilizante, massa seca total e N total que 5 e 10 cm. 70%URP+30%U apresentou maior altura, massa seca total e N total que 100%U quando aplicados abaixo da linha de semeadura. Nas aplicações 10 cm ao lado da linha de semeadura observou-se menor CE na linha do fertilizante comparado com as de 0 cm. No LVAd, massa seca total e N total apresentaram comportamento quadrático em resposta ao aumento da dose de N. Misturas de U e URP são eficientes quando aplicadas na semeadura do milho e elevadas doses interferem no desenvolvimento inicial de plantas de milho mesmo em uma posição considerada adequada no LVAd. / Blends of urea (U) and polymer sulfur coated urea (PSCU) can be an alternative to improve nitrogen (N) use efficiency (NUE) and reduce costs when applied in a single application in agricultural crops. Different indices of NUE (apparent crop recovery applied N (RE), physiological efficiency of applied N (PE), internal utilization efficiency of N (IE), agronomic efficiency of applied N (AE), partial factor productivity of applied N (PFP)) were investigated in field experiments, as well as nutrient uptake and partitioning in corn (Zea mays L.) with blends of U and PSCU applied in a single application of 180 kg N ha-1 at sowing in a Typic Haplustox and Rhodic Haplustox. It was included a treatment with urea in conventional management (UCM). The blends of U and PSCU were incorporated in a band 5 cm below and 10 cm to the side of the seed row. Plants were sampled at four growth stages and divided into four fractions for nutrient determination. In the Typic Haplustox, treatments with 100%PSCU, 70%PSCU+30%U and 60%PSCU+40%U had higher grain yield than control treatment (without N application); treatments with 100%U and UCM had lesser PE and IE than 100%PSCU; all the N treatments had higher total biomass and total N uptake than control at physiological maturity (R6); treatment with 70%PSCU+30%U had higher total S uptake than control and UCM at R6. There weren\'t differences between treatments for grain yield, indices of NUE, and total nutrient uptake at R6 in the Rhodic Haplustox. In greenhouse experiments, electrical conductivity (EC) and pH of soil, height, diameter, dry weight and nitrogen uptake in early plant growth were evaluated using a blend of 70%PSCU+30%U applied in a band at sowing maize in the following ways: 1) applying a rate equivalent to 180 kg N ha-1 in different positions (5 , 10 and 15 cm below and 0, 5 and 10 cm to the side of the seed) in a Rhodic Eutrustox and comparing with 100%U; 2) varying rates (equivalent to 0, 90, 180, 360, 540 kg N ha-1) in a position considered adequate (15 cm below and 10 cm to the side of the seed) in a Rhodic Eutrustox and Typic Haplustox. The N fertilizer application 15 cm below of the seed had higher EC in fertilizer row at 9-18cm, pH in fertilizer row, total dry weight and total N uptake than 5 and 10 cm below of the seed. The treatment with 70%PSCU+30%U had higher height, total dry weight and total N uptake than 100%U in the application 0 cm to the side of the seed. The N fertilizer application 10 cm to the side of seed had lesser EC in the fertilizer row than 0 cm. In the Typic Haplustox, total dry weight and total N uptake had quadratic behavior in response to increase N rates. Blends of U and PSCU are efficient when applied at corn sowing and can affect early plant growth at high rates even in a position considered adequate in Typic Haplustox.
13

Misturas de ureia revestida com polímeros e ureia convencional na adubação da cultura de milho / Blends of polymer coated urea and conventional urea in maize fertilization

Hugo Abelardo González Villalba 22 January 2014 (has links)
Fertilizantes de liberação controlada como a ureia revestida com polímeros podem propiciar melhor sincronia entre a disponibilidade de nitrogênio (N) no solo e as exigências do nutriente pela cultura de milho (Zea mays L.). Para avaliar o efeito de diferentes estratégias de uso da ureia revestida com polímeros na disponibilização de nitrogênio inorgânico, nitrato (NO3-) e amônio (NH4+) no solo durante o ciclo da cultura de milho, e na produtividade final de grãos, foram conduzidos experimentos na safra 2012/2013, em duas condições edafoclimáticas no município de Piracicaba, Estado de São Paulo. Os solos dos experimentos foram: Latossolo Vermelho Distrófico (LVd) e Latossolo Vermelho Amarelo Distrófico (LVAd). O delineamento experimental foi de blocos completos ao acaso com quatro repetições e os tratamentos constaram da aplicação da dose de 180 kg ha-1 de N, utilizando-se duas fontes de N, ureia revestida com polímeros e ureia convencional, aplicadas, respectivamente, nas proporções de 100:0, 90:10, 80:20, 70:30, 60:40, 50:50 e 0:100%, além de um tratamento com ureia em manejo convencional com aplicação parcelada (20% na semeadura e 80% em cobertura entre os estádios V4-V6), e o controle sem aplicação de N. Foi semeado híbrido de milho com elevado potencial de produtividade. Os fertilizantes aplicados na semeadura foram incorporados a 5 cm de profundidade e 10 cm ao lado da linha de milho. Para determinar o teor de nitrogênio inorgânico no solo, nas camadas de 0-0,1, 0,1-0,2, 0,2-0,4 e 0,4-0,6 m, foram realizadas amostragens na semeadura e em V4, V12 e R3 no LVd e na semeadura e em V6, V14 e R4 no LVAd. Produtividade de grãos, massa seca da parte aérea, acúmulo de N na parte aérea, exportação de N nos grãos, e a eficiência de utilização interna de nitrogênio foram avaliados na maturidade fisiológica da cultura. Os resultados foram submetidos à análise de variância e quando observado efeito significativo de tratamentos, foram realizadas análises de contraste de médias (p<=0,1). A produtividade máxima nos dois experimentos foi da ordem de 10 Mg ha-1 de grãos de milho. Nos dois experimentos a ureia revestida com polímeros disponibilizou nitrogênio mineral no solo ao longo de todo o ciclo da cultura de milho, o que resultou no LVAd em produtividade de grãos mais elevada em relação à utilização de ureia convencional, diferentemente do ocorrido no LVd, onde não foram observados efeitos de tratamentos. A utilização de misturas de URP e U na adubação da cultura do milho, com proporções variando de 100% a 50% da fonte de liberação controlada, mostrou-se eficiente e pode ser considerada uma estratégia que fornece N conforme a exigência da cultura, o que resulta em maior produtividade de grãos em condições edafoclimáticas favoráveis. / Controlled release fertilizers such polymer coated urea can provide better synchrony between nitrogen (N) availability in the soil and its requirements by maize (Zea mays L.). To evaluate the effect of different use strategies of polymer coated urea on the availability of inorganic nitrogen, nitrate (NO3-) and ammonium (NH4+) throughout the crop cycle, and the grain yield, field experiments were carried out in the 2012-2013 growing season, in two soil-climatic conditions, in Piracicaba, São Paulo State. The soils were a clayey and a sandy Oxisol. The experimental design was randomized blocks with four replications, and the treatments consisted of 180 kg N ha-1, using two sources of N, polymer coated urea and conventional urea, respectively, in proportions of 100:0, 90:10, 80:20, 70:30, 60:40, 50:50% and 0:100%, besides a treatment with urea in conventional management, split-applied (20% at seeding and 80% side-dressed in V4-V6 corn growth stage) and a control (without N). Maize hybrid with high productivity potential was used. The fertilizers applied at seeding were placed in bands 5 cm depth and 10 cm aside the corn row. To determine the inorganic nitrogen content in the soil at 0-0.1, 0.1-0.2, 0.2-0.4 and 0.4-0.6 m soil layers, samples were collected at seeding, V4, V12 and R3 corn growth stage in the clayey Oxisol, and at sedding, V6, V14 and R4 in the sandy Oxisol. Grain yield, aerial biomass, nitrogen uptake by the aerial biomass, grain nitrogen uptake and internal utilization efficiency of nitrogen were evaluated. Data were analyzed using analysis of variance and when differences were detected, means where separated using contrast test (p<=0.1). The maximum maize grain yield in the experiments was approximately 10 Mg ha-1. In the two experiments, polymer coated urea led to a greater inorganic nitrogen availability throughout the maize cycle, which resulted in higher yield comparing to the use of conventional urea in the sandy Oxisol, not thus in the clayey Oxisol, where no effects of treatments in grain yield were observed. The use of blends of polymer coated urea and conventional urea in maize fertilization, with ratios ranging from 100 to 50% of the controlled release source, was efficient and can be considered a strategy that supplies N as the crop demands it, and thus lead to a greater maize grain yield under agro-climatic favorable conditions.
14

Synthesis of zeolites and their application as soil amendments to increase crop yield and potentially act as controlled release fertilizers

Jakkula, Vijay S. January 2005 (has links)
Zeolites have been used in agriculture since the 1960s, due to the effectiveness of these crystalline microporous solids as soil amendments for plant growth, their cation exchange capacity (CEC) and slow-release fertilizer properties. Most work on slow-release fertilizers has focused on natural Clinoptilolite, Phillipsite and Chabazite. The aim of this study was to synthesize zeolites, study their effectiveness as soil amendments and their ability to act as controlled release fertilizers to decrease nitrate leaching. Nitrate pollution of groundwater is a major agro-environmental concern. The zeolites Phillipsite and Linde-type F were synthesized from aluminosilicate gels; ion exchanged to introduce ammonium and characterized using X-ray diffraction (XRD), X-ray fluorescence (XRF), Thermo-gravimetric analysis (TGA) and Scanning electron microscopy (SEM) techniques, both before and after ion exchange. Ammoniumexchanged Phillipsites (natural and synthetic), ammonium-exchanged synthetic Linde-type F (the zeolite having highest affinity towards ammonium) and ammonium exchanged Phillipsites (high crystalline and high aluminium) were compared with conventional NPK fertilizer.Three glasshouse experiments were performed to study the effects of zeolite-amended soils on maize growth. Ion exchanged synthetic and natural Phillipsites were first used as soil amendments (w/w 2, 4, 8% zeolite to soil). Synthetic Phillipsite, at 2% loading, resulted in the most significant improvement in both plant growth and phased ammonium release. The synthetic ammonium-exchanged zeolites Phillipsite and Linde-type F (at w/w 1, 2, 4%) were then compared; synthetic Phillipsite, at 2% loading, again resulted in the most significant plant growth response with an increase (≥15%) in shoot dry weight and a decrease (≥30%) in nitrate leaching. Experiments using unexchanged synthetic Phillipsite (at w/w 2%), but with added NPK fertilizer, showed increased plant growth and decreased nitrate leaching, compared with parallel experiments containing unexchanged synthetic Linde-type F (at w/w 2%) and a conventional fertilizer amended soil. This revealed the beneficial effect of Phillipsite for soil amendment, even without ion exchange to the ammonium form. To study the physico-chemical properties affecting the release of ammonium from the Phillipsite framework; high crystalline/low aluminium and low crystalline/high aluminium forms were synthesized and ion exchanged. Both forms were introduced as soil amendments (at w/w 1 and 2%) and experiments showed that the lower zeolite crystallinity decreased cation exchange and therefore decreased nitrate leaching. Experimental results from the glasshouse experiments and cation exchange capacity (CEC) experiments suggest that synthetic Phillipsite, at lower loadings (1 and 2% w/w zeolite to soil) have most potential as soil amendments for both plant growth and controlled-release applications. This conclusion is supported by soil leachate and shoots dry weight analysis. Furthermore, Phillipsite, synthesized in a low crystalline and low ammonium form, may be an even better soil amendment for controlled release of ammonium, which will thereby further decrease nitrate pollution.
15

Superação de dormência e produção de mudas de Anacauíta Schinus molle L. / Overcome dormancy and seedlings production of anacauita Schinus molle L.

Leal, Cintia Müller 07 December 2015 (has links)
Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2018-07-10T17:45:09Z No. of bitstreams: 1 Dissertação Versão Final.pdf: 2650724 bytes, checksum: 0735a2bb9f056999c0b6a14b82b893b4 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-07-16T17:00:11Z (GMT) No. of bitstreams: 1 Dissertação Versão Final.pdf: 2650724 bytes, checksum: 0735a2bb9f056999c0b6a14b82b893b4 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2018-07-16T17:36:03Z (GMT) No. of bitstreams: 1 Dissertação Versão Final.pdf: 2650724 bytes, checksum: 0735a2bb9f056999c0b6a14b82b893b4 (MD5) / Made available in DSpace on 2018-07-16T17:36:13Z (GMT). No. of bitstreams: 1 Dissertação Versão Final.pdf: 2650724 bytes, checksum: 0735a2bb9f056999c0b6a14b82b893b4 (MD5) Previous issue date: 2015-12-07 / Anacauíta (Schinus molle L.) é uma espécie arbórea de ocorrência nativa no Rio Grande do Sul, pioneira de pequeno porte, com importância ecológica, bioquímica e farmacológica, contudo suas sementes apresentam dormência, fato que dificulta a produção de mudas em escala comercial. Este trabalho objetivou avaliar métodos de superação de dormência das sementes de S. molle de um lote com 15 meses de armazenamento em câmara fria seca e germinação inicial de 5% quando submetidas a tratamento para superação de dormência com ácido sulfúrico por 160 minutos, utilizando diferentes tempos de escarificação mecânica (150, 300, 450 e 600 segundos) em escarificador elétrico equipado com lixa grão 80. O tratamento de 150 segundos de escarificação mecânica proporcionou maior percentual de germinação (61%), menor número de sementes mortas e plântulas anormais, maior massa seca e comprimento de plântulas aos sete dias, maior embebição e maior índice de velocidade de emergência (2,28). Para a produção de mudas desta espécie foram testados dois volumes de tubetes (100 e 175 mL) e quatro níveis de adubação com fertilizante de liberação controlada (FLC) Osmocote Plus, em um experimento fatorial 2 x 4. Os níveis de adubação com FLC foram zero, quatro, oito e doze gramas por litro de substrato. Os resultados quanto aos parâmetros de crescimento e qualidade de mudas, onde foram avaliados altura, diâmetro do coleto, número de folhas, relação altura/diâmetro do coleto, massa seca da raiz, massa seca da parte aérea, massa seca total, relação massa seca da parte aérea e massa seca da raiz, volume de raiz, índice de qualidade de Dickson, índice de clorofila, teor de clorofila a, clorofila b e carotenoides ao longo de 120 dias após a emergência das plântulas, revelou que o tubete de 175 mL e a dosagem de oito gramas de FLC por litro de substrato foi superior aos demais tratamentos por produzir mudas de anacauíta de alta qualidade. / Anacauita (Schinus molle L.) is arborea, native species in a Rio Grande do Sul small pioneer with ecological, biochemical and pharmacological importance, but its seeds present dormancy , a fact that hinders the production of seedlings on a commercial scale. This study aimed at evaluating methods of overcoming seed dormancy of S. molle of a batch of 15 months of storage in dry cold chamber and 5% germination when undergoing treatment to overcome dormancy with sulfuric acid for 160 minutes, using different times mechanical scarification (150, 300, 450 and 600 seconds) in electric scarifier equipped with 80 grit sandpaper. Treatment of 150 seconds of mechanical scarification showed higher germination percentage (61%), fewer dead seeds and abnormal seedlings, imbibition largest and most emergency velocity index (2.28). For the production of seedlings of this species were tested two volumes of tubes (100 and 175 mL) and four levels of fertilizer controlled release fertilizer (CRF) Osmocote Plus in 2 x 4 factorial experiment. Nutrient levels were CRF zero, four, eight and twelve grams per liter of substrate. The results regarding the growth parameters and quality seedlings, which were assessed height, stem diameter, number of leaves, height / stem diameter, root dry mass, dry mass of shoots, total dry matter, dry weight ratio of shoot and root dry mass, root volume, Dickson quality index, chlorophyll index, chlorophyll content a, chlorophyll b and carotenoids over 120 days after seedling emergence, revealed that the plastic tube 175 ml and the dose of CRF eight grams per liter substrate was superior to the other treatments for producing seedlings of high quality anacauita.
16

Accelerated Pot-in-Pot using Double Cropped Retractable Roof Greenhouse Grown Tree Liners

Rivera, Dania 17 December 2010 (has links)
No description available.
17

Quantifying Impacts of Deer Browsing and Mitigation Efforts on Hardwood Forest Regeneration

Caleb H Redick (8067956) 03 December 2019 (has links)
<p>Due to overpopulation and resource-poor habitat structure, deer threaten the<a> future of oak and other browse-sensitive species in hardwood forests. </a>Appropriate tools must be used to ensure desirable, diverse, and ecologically stable regeneration of future forests and the sustainability of native plant communities. We performed two experiments and a review to examine the effectiveness of available methods for managing browse of hardwood seedlings and to discover how these interact with each other and other silvicultural methods. First, we examined how fencing interacts with controlled-release fertilization, seed source (genetically select and non-select), and site type (afforested and reforested sites) to enhance the regeneration of planted northern red oak (<i>Quercus rubra </i>L.), white oak (<i>Quercus alba</i>), black cherry (<i>Prunus serotina</i>), and black walnut (<i>Juglans nigra</i>) at five sites in Indiana. Fencing proved to be the greatest determinant of seedling growth, survival, and quality. Fertilizer enhanced the early growth of white oak and black cherry, though for black cherry this occurred only inside fences. Select seed sources grew better and showed greater quality; however, the survival of select seedlings was limited by deer browse in absence of fences. Trees at afforested sites had lower survival if left non-fenced. Secondly, we also investigated how fencing and invasive shrub removal affected natural regeneration, species richness, and ground-layer plant cover under closed-canopy forests. Honeysuckle (<i>Lonicera maackii</i>) removal had a variable effect depending on species and site. Positive effects were most common for shade-intolerant species, while negative effects occurred for a few shade-tolerant species at some sites. Deer fencing had a positive effect on cherry and hackberry seedling density, and a negative effect on elm seedling density. Honeysuckle and deer fencing interacted antagonistically in some instances. Fencing without honeysuckle removal resulted in lower elm abundance and herbaceous-layer cover. In the densest invasions, leaving honeysuckle intact resulted in a complete lack of recruitment into the sapling layer. Our experiment suggests that invasive shrub removal and fencing be done together. Finally, we synthesized the existing literature on browse management options for hardwood regeneration to evaluate their relative effectiveness. Fences, tree shelters, repellents, facilitation by neighboring plants, deer population control, timber harvest, and slash all had positive effects on height growth of regenerating seedlings under deer browse pressure. Fences were more effective at reducing browse than repellents, while fertilizers increased browse and had no effects on growth. </p>

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