Cover Crop Effects on the Activity-Density of the Weed Seed PredatorHarpalus rufipes(Coleoptera: Carabidae)

Cover crop systems were investigated in 2004 and 2005 for their effects on the activity-density (a function of movement and density) of a promising group of weed biocontrol organisms, the ground beetles collectively known as carabids, with particular emphasis on a beneficial carabid speciesHarpalus rufipesDeGeer. MarkedH. rufipesreleased into pea/oat–rye/vetch cover crop plots were more than twice as likely to be recaptured within the same plots as beetles released in nonvegetated fallow plots (18 and 8%, respectively). Marked beetles released into fallow plots were more than twice as likely to leave their plots and be recaptured in pea/oat–rye/vetch plots as vice versa (13 vs. 5%), indicating a clear preference for habitat with vegetative cover. Overall recapture rates were not different between treatments. UnmarkedH. rufipesactivity-density was also higher in pea/oat–rye/vetch compared to fallow plots. Additionally, five cover crop systems, including the fallow and pea/oat–rye/vetch treatments, and two residue management methods (conventional and zone tillage) were investigated from June to August in 2005 for their effects onH. rufipesactivity-density. Corn was planted in 2005 into residues of the five cover crop systems grown in 2004.H. rufipesactivity-density was higher in zone and conventionally tilled corn planted in pea/oat–rye/vetch residues and conventionally tilled corn planted in red clover/oat residues than in any other cover crop and residue management combination. Pea/oat–rye/vetch cover crop systems are apparently beneficial forH. rufipesduring the cover crop year as well as in subsequent crops planted into this cover crop's residues. This system was not the least disturbed system but, based on the number of tillage events, represented a medium level of disturbance among the various systems. Thus, some level of disturbance might be beneficial forH. rufipes, but how and when that soil disturbance occurs requires further research to determine the best means of conserving this species.

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Effects of Initial Seed-Bank Density on Weed Seedling Emergence during the Transition to an Organic Feed-Grain Crop Rotation

Weed Science ◽

10.1614/ws-09-031.1 ◽

2009 ◽

Vol 57 (5) ◽

pp. 533-540 ◽

Cited By ~ 10

Author(s):

Richard G. Smith ◽

Randa Jabbour ◽

Andrew G. Hulting ◽

Mary E. Barbercheck ◽

David A. Mortensen

Keyword(s):

Seed Bank ◽

Weed Management ◽

Cover Crop ◽

Management Practices ◽

Transition Period ◽

Red Clover ◽

Weed Seed ◽

Weed Species ◽

Organic Certification ◽

Weed Seeds

The transition period to certified organic production can present a significant weed management challenge for growers. Organic certification requires that prohibited fertilizers and pesticides must not have been used for 36 mo before harvest of the first organic crop. Understanding how organic management practices and initial weed seed-bank densities affect weed population dynamics during the transition period may improve weed management efficacy and adoption of organic practices. We examined how tillage systems (full or reduced) and cover crop species planted during the first transition year (rye or a mixture of timothy and red clover) affect the seedling densities of three common annual weed species, common lambsquarters, velvetleaf, and foxtail spp., during the 3-yr transition period. Weed seeds were applied in a one-time pulse at the beginning of the study at three densities, low, medium, and high (60, 460, and 2,100 seeds m−2, respectively), and cumulative seedling densities of each species were assessed annually. Treatment factors had variable and species-specific effects on weed seedling densities. In general, the full-tillage system, with an initial cover crop of timothy and red clover, resulted in the lowest density of weed seedlings following seed-bank augmentation. There was little consistent association between the initial densities of applied weed seeds in the weed seed bank at the start of the transition and weed seedling densities at the end of the transition period. This suggests that when multiple crop and weed cultural management practices are employed during the organic transition period, initial failures in weed management may not necessarily lead to persistent and intractable annual weed species management problems following organic certification.

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Pest and weed seed predation in field defects within oilseed rape crops

ARPHA Conference Abstracts ◽

10.3897/aca.2.e37075 ◽

2019 ◽

Vol 2 ◽

Author(s):

Ezequiel González ◽

Miroslav Seidl ◽

Martin Štrobl ◽

Tomáš Kadlec ◽

Marco Ferrante ◽

...

Keyword(s):

Oilseed Rape ◽

Seed Predation ◽

Weather Conditions ◽

Ground Beetles ◽

Agricultural Landscapes ◽

Feeding Guilds ◽

Weed Seed ◽

Weed Species ◽

Activity Density ◽

Field Defects

Non-crop habitats can act as refuge for insects in agricultural landscapes and increase ecosystem services (ESs) in neighboring arable fields. Among the different types of non-crop habitats, field defects are temporary patches where sown plants are poorly developed and other plant species emerge. These defects can be common and large in years with extreme weather conditions. However, their relevance as habitat for beneficial insects and ESs provision is unknown. Here, we quantified two ESs (pest and weed seed predation) in field defects within oilseed rape crops and related ESs levels with the activity-density of ground beetles and temperature. In 10 fields, we used artificial caterpillars made of plasticine and seed cards of two weed species (Taraxacum sp. and Stellaria sp.) to quantify ESs in two sampling periods (spring and summer) and in three habitat types: field defects, standardly grown crop (field interiors) and crop-defect boundaries. Ground beetles were sampled using pitfall traps and classified into feeding guilds and body size classes. Insects and mammals were the main pest predators and predation increased in summer, but did not differ among habitats. Seed predation rates for both species were significantly higher in summer. Predation of Taraxacum seeds was higher at field interiors, whereas predation of Stellaria was significantly higher at field interiors and defects, compared to crop-defect boundaries. Insect predation increased with the activity-density of medium and large carnivorous carabids, whereas seed predation for both weed species was positively related to the activity-density of medium-sized herbivorous carabids. Finally, temperature was negatively linked to predation of artificial caterpillars and seeds of Taraxacum.

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Postdispersal Weed Seed Predation and Invertebrate Activity Density in Three Tillage Regimes

Weed Science ◽

10.1614/ws-d-15-00030.1 ◽

2015 ◽

Vol 63 (4) ◽

pp. 828-838 ◽

Cited By ~ 8

Author(s):

Rocio van der Laat ◽

Micheal D. K. Owen ◽

Matt Liebman ◽

Ramon G. Leon

Keyword(s):

Seed Predation ◽

Ground Beetles ◽

Reduced Tillage ◽

Zero Tillage ◽

Weed Seed ◽

Common Waterhemp ◽

Common Lambsquarters ◽

Field Crickets ◽

Activity Density ◽

Choice Feeding

Field experiments were conducted near Boone, IA, to quantify postdispersal seed predation of common lambsquarters and common waterhemp in corn (2003) and soybean (2004) managed with conventional, reduced, and zero-tillage systems. Seed predation in each tillage regime was quantified using selective exclusion treatments during July through September 2003 and June through October 2004. In addition, the activity density of ground-dwelling invertebrates was estimated with pitfall traps. Choice and no-choice feeding trials were conducted in the laboratory using the most abundant weed seed predators found in the field to determine seed preferences of the potential predator organisms. The greatest seed loss occurred during July and August. In 2003, seed predation was lower in zero tillage than in conventional and reduced tillages, but no differences in seed predation between tillage regimes were observed in 2004. Maximum seed predation for common lambsquarters was 53% in 2003 and 64% in 2004. Common waterhemp seed predation reached 80% in 2003 and 85% in 2004. The majority of seed predation was by invertebrate organisms. The most common invertebrate species captured with pitfall traps were field crickets (Gryllus pennsylvanicusDe Geer [Gryllidae, Orthoptera]) and ground beetles (Harpalus pensylvanicusBurmeister [Coleoptera, Carabidae]). In 2003, field crickets were relatively more abundant in conventional and reduced tillage than in zero-tillage plots. In 2004, field crickets were more abundant in the reduced tillage than in the other two tillage regimes. No differences were detected for ground beetles among tillage regimes (P = 0.57). Choice and no-choice feeding experiments confirmed the preferences of field crickets and ground beetles for common lambsquarters and common waterhemp seeds over the larger seeds of giant foxtail and velvetleaf. Under field conditions, the activity density of field crickets was a significant predictor of common lambsquarters (r2= 0.47) and common waterhemp (r2= 0.53) seed predation. Positive relationships were also detected between the activity density of ground beetles and common lambsquarters (r2= 0.30) and common waterhemp (r2= 0.30) seed predation. This research demonstrated that weed seed predation is an important component affecting weed seedbanks and that crop management practices that favor the activity of predators such as field crickets or ground beetles could influence weed populations. Also, the results suggested that tillage is more important in determining the number of weed seeds available on the soil surface to predators than directly affecting predator activity density.

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The impact of reduced tillage and distance to field margin on predator functional diversity

Journal of Insect Conservation ◽

10.1007/s10841-022-00370-x ◽

2022 ◽

Author(s):

Stine K. Jacobsen ◽

Lene Sigsgaard ◽

Anna B. Johansen ◽

Kristian Thorup-Kristensen ◽

Per M. Jensen

Keyword(s):

Functional Diversity ◽

Ground Beetles ◽

Soil Disturbance ◽

Reduced Tillage ◽

Pitfall Traps ◽

Natural Habitats ◽

Activity Density ◽

Soil Disturbances ◽

Abundance And Diversity ◽

The Impact

Abstract Introduction Agricultural intensification results in biodiversity loss through land conversion and management practices which negatively impact arthropods. The abundance and diversity of ground-dwelling predators, e.g. ground beetles (Coleoptera: Carabidae) and spiders (Araneae), are negatively affected by soil disturbances such as tillage. Reducing soil disturbances can potentially conserve arthropod populations in the field and reduce the use of chemical pest controls. The present study investigated the ground-dwelling predatory community using pitfall traps in cereal fields with three different levels of soil disturbance: conventional tillage, reduced tillage and no tillage under Conservation Agriculture management, in 2018 and 2019. Pitfall traps were placed in transects from the field margins. Overall, the activity-density of ground-dwelling predators was higher in fields with minimum soil disturbance and generally declined with increased distance to semi-natural habitats. Functional diversity, expressed by the body size of ground beetles, was also affected by soil disturbances; large ground beetles more consistently occurred in CA, while few or none of the largest ground beetles were found in RT and CT. A higher sample-heterogeneity in less disturbed fields was indicated by a more variable median and higher skewness in the number of predators in those fields. In 2019 only, species diversity was higher along field edges bordering semi-natural habitats when compared to the cropped area. Our results show that reduced tillage supports predator arthropod communities at a local scale: It also bolsters agro-ecosystem resilience by promoting a higher activity-density and by increasing the heterogeneity and functional diversity of ground-dwelling predators. Implications for insect conservation The results obtained in the present study show that soil disturbances significantly influence arthropod abundance and diversity. Conservation of epigeic natural enemies in the agricultural landscape is improved by reducing soil-disturbing events such as tillage.

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Cover crop residue management for optimizing weed control

Plant and Soil ◽

10.1007/s11104-008-9827-6 ◽

2008 ◽

Vol 318 (1-2) ◽

pp. 169-184 ◽

Cited By ~ 56

Author(s):

H. Marjolein Kruidhof ◽

Lammert Bastiaans ◽

Martin J. Kropff

Keyword(s):

Weed Control ◽

Cover Crop ◽

Crop Residue ◽

Residue Management ◽

Crop Residue Management

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Temporal Change of Soil Carbon on a Long-Term Experimental Site with Variable Crop Rotations and Tillage Systems

Agronomy ◽

10.3390/agronomy10060840 ◽

2020 ◽

Vol 10 (6) ◽

pp. 840 ◽

Cited By ~ 1

Author(s):

Ahmed Laamrani ◽

Paul R. Voroney ◽

Aaron A. Berg ◽

Adam W. Gillespie ◽

Michael March ◽

...

Keyword(s):

Winter Wheat ◽

Soil Carbon ◽

Cover Crops ◽

Cover Crop ◽

Red Clover ◽

Conventional Tillage ◽

Crop Rotations ◽

Tillage Practices ◽

No Till

The impacts of tillage practices and crop rotations are fundamental factors influencing changes in the soil carbon, and thus the sustainability of agricultural systems. The objective of this study was to compare soil carbon status and temporal changes in topsoil from different 4 year rotations and tillage treatments (i.e., no-till and conventional tillage). Rotation systems were primarily corn and soy-based and included cereal and alfalfa phases along with red clover cover crops. In 2018, soil samples were collected from a silty-loam topsoil (0–15 cm) from the 36 year long-term experiment site in southern Ontario, Canada. Total carbon (TC) contents of each sample were determined in the laboratory using combustion methods and comparisons were made between treatments using current and archived samples (i.e., 20 year and 9 year change, respectively) for selected crop rotations. Overall, TC concentrations were significantly higher for no-till compared with conventional tillage practices, regardless of the crop rotations employed. With regard to crop rotation, the highest TC concentrations were recorded in corn–corn–oats–barley (CCOB) rotations with red clover cover crop in both cereal phases. TC contents were, in descending order, found in corn–corn–alfalfa–alfalfa (CCAA), corn–corn–soybean–winter wheat (CCSW) with 1 year of seeded red clover, and corn–corn–corn–corn (CCCC). The lowest TC concentrations were observed in the corn–corn–soybean–soybean (CCSS) and corn–corn–oats–barley (CCOB) rotations without use of cover crops, and corn–corn–soybean–winter wheat (CCSW). We found that (i) crop rotation varieties that include two consecutive years of soybean had consistently lower TC concentrations compared with the remaining rotations; (ii) TC for all the investigated plots (no-till and/or tilled) increased over the 9 year and 20 year period; (iii) the no-tilled CCOB rotation with 2 years of cover crop showed the highest increase of TC content over the 20 year change period time; and (iv) interestingly, the no-till continuous corn (CCCC) rotation had higher TC than the soybean–soybean–corn–corn (SSCC) and corn–corn–soybean–winter wheat (CCSW). We concluded that conservation tillage (i.e., no-till) and incorporation of a cover crop into crop rotations had a positive effect in the accumulation of TC topsoil concentrations and could be suitable management practices to promote soil fertility and sustainability in our agricultural soils.

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Long-term data reveal unimodal responses of ground beetle abundance to precipitation and land use but no changes in taxonomic and functional diversity

Scientific Reports ◽

10.1038/s41598-021-96910-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Petr Zajicek ◽

Ellen A. R. Welti ◽

Nathan J. Baker ◽

Kathrin Januschke ◽

Oliver Brauner ◽

...

Keyword(s):

Land Use ◽

Functional Diversity ◽

Spatial Scales ◽

Ground Beetle ◽

Temporal Trends ◽

Ground Beetles ◽

Community Change ◽

Ecological Communities ◽

Activity Density

AbstractWhile much of global biodiversity is undoubtedly under threat, the responses of ecological communities to changing climate, land use intensification, and long-term changes in both taxonomic and functional diversity over time, has still not been fully explored for many taxonomic groups, especially invertebrates. We compiled time series of ground beetles covering the past two decades from 40 sites located in five regions across Germany. We calculated site-based trends for 21 community metrics representing taxonomic and functional diversity of ground beetles, activity density (a proxy for abundance), and activity densities of functional groups. We assessed both overall and regional temporal trends and the influence of the global change drivers of temperature, precipitation, and land use on ground beetle communities. While we did not detect overall temporal changes in ground beetle taxonomic and functional diversity, taxonomic turnover changed within two regions, illustrating that community change at the local scale does not always correspond to patterns at broader spatial scales. Additionally, ground beetle activity density had a unimodal response to both annual precipitation and land use. Limited temporal change in ground beetle communities may indicate a shifting baseline, where community degradation was reached prior to the start of our observation in 1999. In addition, nonlinear responses of animal communities to environmental change present a challenge when quantifying temporal trends.

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Effect of Cover Crops on Yield and Leaf Nutrient Concentrations in an Organic Honeycrisp Apple (Malus domestica ‘Honeycrisp’) Orchard in Nova Scotia, Canada

HortScience ◽

10.21273/hortsci10615-16 ◽

2016 ◽

Vol 51 (11) ◽

pp. 1378-1383

Author(s):

Mehdi Sharifi ◽

Julia Reekie ◽

Andrew Hammermeister ◽

Mohammed Zahidul Alam ◽

Taylor MacKey

Keyword(s):

Nova Scotia ◽

Malus Domestica ◽

Cover Crops ◽

Cover Crop ◽

Red Clover ◽

Nutrient Concentrations ◽

Soil Productivity ◽

Total N ◽

Leaf Nutrient Concentrations ◽

K Concentration

There is an increasing interest for use of cover crops in orchards; however, the species that are most likely to be successfully implemented and their impact on yield and soil productivity have not been fully explored under Maritimes climate. This study investigated the effect of various cover crops treatments on organic apple (Malus domestica Borkh cv. Honeycrisp) yield and leaf nutrient concentrations in Nova Scotia over 3 years. Various cover crop mixtures including legumes, cereals, and grasses were planted using a modified Swiss Sandwich System (SSS). The cover crops treatments did not affect apple yield. In 2012, the input of biomass to the soil was 89% and 144% greater for alfalfa (ALF) and other cover crop treatments than unseeded (CON) treatment, respectively. The pea, oats, vetch mixture (POVM) contributed 24% higher biomass N to soil compared with average of other cover crops in 2012. Soil available K concentration in the tilled strip was increased in the 3rd year of the study compared with the initial values across cover crop treatments. The red clover oats mixture (RCOM), POVM, and Triple Mix (TM) treatments appeared to add the greatest amount of available K to the soil among treatments. The CON, TM, and ALF treatments resulted in higher leaf Mn concentration in only 2012 and CON, sweet clover and oats mixture (SCOM), and ALF resulted in higher leaf P concentration in 2014, compared with other treatments. Cover crops did not compete with apple trees and their most beneficial and consistent contribution was to total C, total N, and K input to the soil.

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