Crop Practices Research Articles

Agricultural practices in onion crops and their impact on water quality in Risaralda, Colombia

ABSTRACT The Otún River watershed, located in the Colombian coffee region, provides water to over 700,000 inhabitants of the Risaralda department. Onion (Allium fistulosum) has been cultivated in this area since 1960, and it currently represents an important economic contribution for local farmers who have assimilated the models of intensive agricultural production with the common use of chemical inputs. The aim of this research paper is to identify management practices, and their potential impact on water quality for human supply in the Otún River. Using surveys conducted among local producers, a general farmers group with primary education was identified, who were not members of any producer association (≤9.1). Improper agricultural practices were identified in farms, where up to 1449 L ha−1 of diluted agrochemical supplies are used. Up to 70 different products with a large variety of toxicological categories (from a slightly toxic products class (III) to extremely toxic products (Ia)), for the management of pests and diseases of onion crops. With the Pesticide Impact Rating Index (PIRI) tool, a high impact of pesticide mobility toward water sources and risk to the ecosystem and humans was identified. In the water sources sampled, ten organochlorine pesticides and 16 organophosphate pesticides were detected.

Crop diversification practice faces a tradeoff between increasing productivity and reducing carbon footprints

Increasing crop biodiversity often increases agro-ecosystem services, however, the effects of crop biodiversity on crop yield and environmental benefits are still unclear. Thus, we conducted a 4-yr field experiment in northeastern China including continuous maize (CM), continuous soybean (CS), maize and soybean rotation (M-S), and maize and soybean intercropping (M/S) to evaluate the crop productivity, economic returns, carbon footprint (CF) and carbon sustainability index (CSI) among the cropping system regimes. Compared with CM treatment, M-S and M/S achieved lower energy yield (EY) and maize equivalent economic yield (MEEY), but higher economic returns. The mean annual net revenue of M-S treatment was 7.2% higher, and the mean annual benefit: cost ratio of M-S and M/S treatments were 12.0% and 8.8% higher than those of CM treatment. Based on the life cycle assessment (LCA), lower CFs were observed in the M-S and M/S systems. The CF per unit of area (CFA) of M-S and M/S treatments was 21.4% and 51.3% lower than that of the CM treatment, respectively. The CF per kg of energy yield (CFEY) of M/S treatment was 35.4% lower, compared with that of the CM treatment. The CF per kg of maize equivalent economic yield (CFMEEY) under M/S treatment was 44.0% lower, than that of the CM treatment. Moreover, CF per unit of economic output (CFE) of M/S treatment was 45.0% lower than that of the CM treatment. The highest CSI was observed in M-S treatment, and it was 61.4% higher than that of CM treatment. Our findings indicate that diversified crop practice (e.g. maize-soybean intercropping and rotation systems) could achieve lesser carbon footprint and higher profitability, however, might compromise grain or energy yield.

Initial production of ora-pro-nóbis under influence of weeds

The ora-pro-nobis crop has agricultural potential but little information regarding cropping practices are available. More information about the interference of weeds on ora-pro-nobis is needed. The objective of this work was to study the initial growth and development of ora-pro-nobis under the interference of common weeds. The experiment was conducted in a completely randomized design, with five treatments, composed of ora-pro-nobis in competition with four weed species: slender amaranth ( Amaranthus viridis ), hairy beggarticks ( Bidens pilosa L.), tropical spiderwort ( Commelina benghalensis ), purple nutsedge ( Cyperus rotundus L.), and a weed-free control, with six replicates. Number of leaves, number and length of secondary branches, chlorophyll a , b and total chlorophyll, dry weight of leaves, branches and roots, total nitrogen, crude protein, crude fiber, and total ash were evaluated. Weed competition led to a decrease in growth and development of ora-pro-nobis , reflected in reduction of up to 40% in yield and 23% in protein content

Willingness to Adopt the Recommended Practices of Organic Turmeric among Kandhamal Farmers of Odisha

Turmeric Cultivation is one of livelihood for the Kondh tribes of Kandhamal District of Odisha. These farmers were cultivating this crop with their traditional knowledge of crop practices without any intervention of chemical inputs. From the studies, it is found that farmers of the district were economically and educationally backward. Turmeric of Kandhamal is well known for its healing property, color, aroma etc. and received GI tag for its unique features. From the secondary data it was found that there were few public and private extension actors trying to promote organic recommended package of practices for Turmeric. And, to boost willingness among farmers towards recommended organic Turmeric various socio-economic variables might be responsible. In this view the present study was carried out (2020-21) in Kandhamal district of Odisha to understand attitude towards recommended organic Turmeric and socio-economic variables effecting willingness to adopt organic package of practices of Turmeric. It was found that turmeric growers had medium to high level of willingness to adopt the recommended agricultural practice. And among selected socio-economic variables respondent’s total family member, Members help in family farming and adult male had negative and significantly relationship with willingness to adopt the recommended agricultural practices of organic turmeric. Private extension actors and State Horticulture Department training were continually motivating them to adopt recommended agricultural practices of organic turmeric.

ASSESSMENT AND MAPPING OF RAINFALL EROSIVITY INDEX (R) FOR MAJHA REGION, PUNJAB IS A STATE IN NORTHERN, INDIA

Purpose: This study gives a critical assessment of the rainfall erosivity factor (R) for selected sites in the Majha region, representing different locations use of mean monthly rainfall data. 
 Methodology: By applying empirical methods, the rainfall intensity for all the locations were obtained and was further determined at three different intervals of 30-minutes, 45-minutes and 60-minutes, respectively. The rainfall erosivity factor (R) was calculated by the revised universal soil loss equation (RUSLE).
 Main Findings: Using RUSLE, the rainfall erosivity factor (R) for each of the locations was measured as follows; EI = 3878.49 (MJmmha-1hr-1), EI = 4013.71 (MJmmha-1hr-1), EI = 4302.24 (MJmmha-1hr-1) for Majha region of Amritsar, Tarntaran and Pathankot respectively. A close observation of the data obtained revealed that as rainfall intensity increased with the duration, the rainfall erosivity index reduced or decreased.
 Implications of study: Nevertheless, it is expected that if proper cover crop and management practices are applied despite the region, the study area falls within, rainfall erosivity can be cushioned, thus reducing further erosion tendencies and enhancing food production chances from productive lands within the area.
 The novelty of study: The rainfall erosivity factor (R) was calculated by the revised universal soil loss equation (RUSLE).

Potato cropping system management strategy impacts soil physical, chemical, and biological properties over time

Soil health is essential for agricultural sustainability and environmental quality yet may be degraded by intensive cropping practices. Improved cropping systems and management practices may greatly enhance soil properties associated with soil heath. Four different potato cropping systems, designed to address specific management goals of soil conservation (SC), soil improvement (SI), disease suppression (DS), and a status quo standard rotation (SQ), along with a non-rotation (PP) control, were evaluated for their effects on soil physical, chemical, and biological properties in field trials in Maine, USA. The purpose of the study was to determine how and to what extent these different cropping system approaches and practices would affect soil properties. Cropping systems were established in 2004 and actively managed through 2010, with potato crops also planted in subsequent years (2011−12) to examine residual effects. Cropping system significantly affected many parameters associated with soil health, with effects generally increasing over time as well as having lasting residual effects. All rotations increased aggregate stability, water availability, microbial biomass C, and total C and N compared to no rotation (PP), and 3-yr systems (SI, SC, DS) increased aggregate stability relative to the 2-yr system (SQ). The 3-yr systems with reduced tillage (SI and SC) also increased water availability and reduced bulk density relative to the other systems. However, the SI system, which included yearly compost amendments, resulted in greater increases in total and particulate organic matter (POM) C and N, active C, microbial biomass C, water availability, CEC, concentrations of P, K, Ca, Mg, and S, and lower bulk density than all other rotations. Cropping systems that incorporate management practices such as increased rotation length and the use of cover crops, green manures, reduced tillage, and, particularly, organic amendments, can improve soil physical, chemical, and biological properties associated with soil health.

Monitoring and Mapping Vineyard Water Status Using Non-Invasive Technologies by a Ground Robot

There is a growing need to provide support and applicable tools to farmers and the agro-industry in order to move from their traditional water status monitoring and high-water-demand cropping and irrigation practices to modern, more precise, reduced-demand systems and technologies. In precision viticulture, very few approaches with ground robots have served as moving platforms for carrying non-invasive sensors to deliver field maps that help growers in decision making. The goal of this work is to demonstrate the capability of the VineScout (developed in the context of a H2020 EU project), a ground robot designed to assess and map vineyard water status using thermal infrared radiometry in commercial vineyards. The trials were carried out in Douro Superior (Portugal) under different irrigation treatments during seasons 2019 and 2020. Grapevines of Vitis vinifera L. Touriga Nacional were monitored at different timings of the day using leaf water potential (Ψl) as reference indicators of plant water status. Grapevines’ canopy temperature (Tc) values, recorded with an infrared radiometer, as well as data acquired with an environmental sensor (Tair, RH, and AP) and NDVI measurements collected with a multispectral sensor were automatically saved in the computer of the autonomous robot to assess and map the spatial variability of a commercial vineyard water status. Calibration and prediction models were performed using Partial Least Squares (PLS) regression. The best prediction models for grapevine water status yielded a determination coefficient of cross-validation (r2cv) of 0.57 in the morning time and a r2cv of 0.42 in the midday. The root mean square error of cross-validation (RMSEcv) was 0.191 MPa and 0.139 MPa at morning and midday, respectively. Spatial–temporal variation maps were developed at two different times of the day to illustrate the capability to monitor the grapevine water status in order to reduce the consumption of water, implementing appropriate irrigation strategies and increase the efficiency in the real time vineyard management. The promising outcomes gathered with the VineScout using different sensors based on thermography, multispectral imaging and environmental data disclose the need for further studies considering new variables related with the plant water status, and more grapevine cultivars, seasons and locations to improve the accuracy, robustness and reliability of the predictive models, in the context of precision and sustainable viticulture.

The influence of fertilizer rates and the amount of irrigation on the water-physical properties of the soil under mixed crops

The article studies and analyzes the effect of fertilizer rates and the number of irrigations on the water-physical properties of the soil under mixed crops. In world practice of agricultural crops mixed crops are used, mainly cereals and legumes, to provide an increase in the productivity and quality of crops, they alsocontribute to the maintenance of soil fertility. Long-term studies have shown that alfalfa roots and stubble residues are of great importance for maintaining and restoring soil fertility. First, the soil is enriched with nutrients that can be absorbed by the roots, and thenthe root system enriches the soil with organic matter, which, in turn, improves the water-physical properties of the soil. From our studies we came to the following conclusions: optimization of the amount of fertilizer and irrigation rates in mixed crops of barley and alfalfa has a significant effect on the water-physical properties of the soil. We advise farmers to use organic and mineral fertilizers in alfalfa crops at a rate of 10 t/ha + N 15 P 60 K 30 .

Global warming potential and energy dynamics of conservation tillage practices for different rabi crops in the Indo-Gangetic Plains

A field experiment was conducted during 2007–2019 under various rabi (winter) crops (viz., wheat, maize, barley and mustard) on a Vertisol in sub-tropical Indo-Gangetic Plains (IGP) with different tillage systems to assess energy indices, greenhouse gas (GHG) emission and carbon sustainability index in assured irrigated fields. The tillage systems were: no tillage sown by a zero till drill (NT), no tillage with retention of previous crop residues at 6 t ha−1 and sowing by a happy turbo seeder (HT), and conventional tillage (CT) where sowing was performed by a multi-crop zero till drill after twice harrowing + twice tilling + once rotavator operations. Significantly higher input energy was observed in wheat followed by maize, barley and mustard. Among tillage systems, CT plots consumed higher input energy that was about 20, 21 to 22, 25 to 26 and 20–22% higher than HT and NT in wheat, maize, barley and mustard, respectively. However, output energy and energy use efficiency were highest in HT. The total GHG emission (kg CO2 equivalent ha−1) was highest in wheat (2,351) followed by maize (2,274), barley (1,859) and mustard (1,652). Among tillage systems, CT produced about 31–34%, 33–34%, 37–40% and 28–30% higher GHG emission than HT and NT under wheat, maize, barley and mustard, respectively. The CT plots had lower carbon sustainability index and carbon efficiency than ZT and HT in all crops. In short, HT recorded significantly higher energy use efficiency and lower global warming potential (GWP) than CT in all crops. Thus, HT could be a promising agro-technique for production of rabi crops in the IGP. Among rabi crops, barley production was energy efficient and had less GWP. In rabi crop production, the highest energy sources was mineral fertilizer use (25–49%) and second highest source was irrigation water (14–44%). These can be substituted with use of the organic sources of fertilizers and application of solar and wind power in irrigation, respectively.

Evaluating honey bee foraging behaviour and their impact on pollination success in a mixed almond orchard

Although Apis mellifera is the dominant managed pollinator used to enhance crop production, the variation of its foraging behaviour among crop-cultivars is not considered as a factor influencing pollination success and, thus, yield. Almond production is highly dependent on cross-pollination. Herein, we examined honey bees foraging behaviour and pollen limitation in ‘Nonpareil’ and ‘Independence’ cultivars. Nectar and pollen-foragers differed in the flower handling behaviour, regardless of the cultivar. However, most bees on ‘Independence’ flowers collected pollen in the morning and bees exhibited less floral constancy in this cultivar, potentially promoting cross-pollination. Also, supplementation of ‘Nonpareil’ flowers with ‘Independence’ pollen had a positive effect in nut-set, suggesting that higher visitation rates are needed to increase yield. Our study underlines the importance of integrating behavioural knowledge of pollinators to optimize practices in pollinator-dependent crops.

Event loading drives distribution of the organochlorine pesticide metabolite DDE in a sub-tropical river system, Brisbane River, Australia

Past catchment practices can contribute to environmental impacts for decades following their cessation. We examine the distribution of the prevalent organochlorine pesticide, dichlorodiphenyltrichloroethane (DDT) and its metabolites (DDE, DDD) in the sediments of a sub-tropical river system (Brisbane River, Australia). This study aimed to identify sources of DDT, DDE, DDD into the lower reaches of the Brisbane River. Annual sediment sampling of the lower Brisbane River over a period of 15 years (2001–2015) revealed a significant increase in sediment DDT, DDE and DDD content following major floods. A regional survey detected elevated sediment DDT, DDE and DDD content at 32 of 79 sites sampled; however, these were generally below guideline trigger values. DDE was the sole fraction at all but one site with creek systems dominated by intensive cropping practices identified as legacy sources and major flood events as a driver of elevated sediment DDE content in the lower reaches.

Post-harvest practices of horticultural crops in Nepal: Issues and management

Fruits and vegetables are highly perishable in nature and have a very short shelf-life. During different handling and marketing procedures, there is massive post-harvest loss of horticulture produce, either or both qualitative and quantitative, between harvest and consumption. Factors affecting post-harvest losses differ with topography, varieties of crops, climate, etc. and are difficult to understand. Considering the fact, the present study aims to describe the status of post-harvest losses of horticultural produce and their potential management techniques. Secondary data is used to collect the related information. The demand of high-quality horticulture produce is increasing due to its healthy nutrition. Post-harvest management of the produce includes pre- and post-harvest practices, their handling, packaging, storage, distribution, and marketing. The storage life and marketable quality of the produce can be maximized by limiting (not stopping) the respiration and transpiration through proper control of temperature and relative humidity of the produce. The right selection of packaging materials and technologies play vital role in maintaining product quality and freshness during storage and distribution. Moreover, the innovative techniques like modified active packaging, active and intelligent packaging, controlled atmospheric storage, and use of antimicrobial could extend the shelf life of produce to a significant time. This review mainly focuses on the causes of qualitative and quantitative losses of horticulture produce along with the effective measures to control the losses in Nepalese context. It emphasized on the adoption of innovative technologies to improve the storage life, marketable quality and freshness of the produce.

<b></b>Integrated Sustainability Evaluation of Field Environment for the Combinations of Tillage and Cover Crop Practices by FAO-SAFA (Sustainability Assessment of Food and Agriculture Systems) Applied with a Modified Rating Method

<b></b>Integrated Sustainability Evaluation of Field Environment for the Combinations of Tillage and Cover Crop Practices by FAO-SAFA (Sustainability Assessment of Food and Agriculture Systems) Applied with a Modified Rating Method

Relationship between personal and socio-economic characteristics of the cashewnut growers and their adoption level

India is the largest producer of raw cashew in the world which ranks first in area under cashew (8, 55, 000 ha) with an annual production of 6.20 lakh MT. Nigeria ranks second in area under the cashewnut cultivation, but ranks first in cashewnut production with annual production of 6.36 lakh MT. In the year 2007-2008, India had exported 1,34,340 metrics tonnes of raw cashew valued Rs.11.97crore. The cashew production in Maharashtra is mainly concentrated in Konkan region particularly in Ratnagiri district. In Maharashtra, the area under cashew was 1.65lakh ha. In Ratnagiri, area under cashew was 88,612ha with production of 85,822 tonnes of cashewnuts. The exploratory survey research design was used for the present study. The study was conducted in Ratnagiri district of the Konkan region of Maharashtra state. Three tahsils namely, Khed and Dapoli were selected purposively on the basis of the maximum area under cashewnut cultivation. The main objective of this study is to study the relationship between personal and socio-economic characteristics of the cashewnut growers and their adoption level. It was observed during the study that, The relationship between selected characteristics of the cashew growers and adoption of recommended critical crop management practices for the cashew crop revealed that the characteristics namely age, family size, and number of bearing cashewnut trees were non-significantly related with the adoption level of critical crop management practices for the cashew crop. On the other hand, education, land holding, annual income, age of orchard, production from cashewnut tree, experience in cashew cultivation and market orientation were significantly related with adoption level. The present study was used as a multistage sampling procedure. Collected data were classified, tabulated and analyzed by using statistical methods like frequency, percentage, mean, standard deviation and Chi-square.

The melliferous flora of Veracruz, Mexico

Objective: To contribute to the knowledge of the situation of the melliferous flora in Veracruz for pollinators and to communicate it for the benefit of beekeepers and stingless beekeepers, as well as to develop comprehensive strategies with these activities. Design/Methodology/Approach: The information was obtained through a bibliographic review in reference databases such as Scopus, Web of Science Group, Academic Google, Elsevier and Springer Link, using the following keywords: flora, bees, pollinators, honey, pollen. Results: 63 families were recorded, with 176 genera and 216 species of melliferous flora, finding that the largest number of species are found in the Fabaceae family (20%) and Asteraceae (16.55%). There were also 44 crops with 22 families. Study Limitations/Implications: There were no limitations in conducting this study. Findings/Conclusions: The greatest diversity of melliferous flora species is seen in wild plants, and strategies need to be implemented for their protection and multiplication. For these actions, various actors must be involved at different levels of government, educational and private institutions, civil society, farmers, beekeepers, and stingless beekeeping. Conservation actions include the use of melliferous plants in gardens and their protection in crops, sites surrounding crops and on edges. It is necessary to preserve natural landscapes and restore damaged ones, as well as to lead favorable practices in pollinator-dependent crops.

Influence of rainfall and seasonal crop practices on nutrient and pesticide runoff from soybean dominated agricultural areas in Pampean streams, Argentina

An increase in the spatial variability of rainfall is expected due to climate change. This implies increasing rainfall rates during spring and summer in the Pampas region, Argentina, period of maximum application of agrochemicals, which might cause an increase in pesticides and nutrients carried to surface water systems, as runoff by rainfall is one of the main pathways for diffuse pollution. The crops phenological stage can also affect pesticide and nutrient runoff since the applied agrochemicals and soil cover differ in each stage. In this study, we assessed the influence of rainfall and seasonal crop practices on water quality (nutrient and pesticide concentrations) in three streams in the Pampas region, Argentina. Five sampling campaigns were performed before and after three rainfall events during two different seasons of crop practices (SCP1, SCP2) and the physicochemical characteristics of the stream and runoff water were analyzed. The pesticide concentrations in the streams presented a general increase immediately after the rainfall event. Water quality was also affected, as an increase in ammonium, soluble reactive phosphorus (SRP), biological oxygen demand (BOD), and turbidity was observed. The crops phenological stage influenced pesticide and nutrient types and concentrations detected in the streams. During SCP1, mainly characterized by chemical fallow and sowing of soybean and vegetative growth and flowering of corn, ammonium, SRP, BOD, turbidity, and some pesticides, such as metolachlor, showed significantly higher results than those found in SCP2 (grain filling and vegetative growth of soybean and corn sowing). The pesticide concentrations detected in runoff water depended mostly on the pesticide solubility, the lateral slope of the streams, and the percentage of woody riparian vegetation cover. The results obtained show the relevance of assessing the influence of rainfall and crops phenological stages on the dynamics of surface water and on pesticide and nutrient runoff for environmental monitoring.

Air quality–related health damages of food

Agriculture is a major contributor to air pollution, the largest environmental risk factor for mortality in the United States and worldwide. It is largely unknown, however, how individual foods or entire diets affect human health via poor air quality. We show how food production negatively impacts human health by increasing atmospheric fine particulate matter (PM2.5), and we identify ways to reduce these negative impacts of agriculture. We quantify the air quality-related health damages attributable to 95 agricultural commodities and 67 final food products, which encompass >99% of agricultural production in the United States. Agricultural production in the United States results in 17,900 annual air quality-related deaths, 15,900 of which are from food production. Of those, 80% are attributable to animal-based foods, both directly from animal production and indirectly from growing animal feed. On-farm interventions can reduce PM2.5-related mortality by 50%, including improved livestock waste management and fertilizer application practices that reduce emissions of ammonia, a secondary PM2.5 precursor, and improved crop and animal production practices that reduce primary PM2.5 emissions from tillage, field burning, livestock dust, and machinery. Dietary shifts toward more plant-based foods that maintain protein intake and other nutritional needs could reduce agricultural air quality-related mortality by 68 to 83%. In sum, improved livestock and fertilization practices, and dietary shifts could greatly decrease the health impacts of agriculture caused by its contribution to reduced air quality.

Influence of Cropping Practices on the Persistence and Vertical Migration of Escherichia coli from Wastewater in Hydromorph Soil in Wet Tropical Zone

Little attention is paid to the influence of cultivation practices on the persistence and vertical migration of undesirable bacteria in hydromorphic soils as they have increased the risk of crop recontamination. Therefore the objective of this study was to determine the implication of some cultural practices on the persistence and vertical migration of E. coli in the soil. In this study, raw sewage (single application) and stream water (multiple application) were applied on lettuce, carrot and aubergine plots. The results revealed that overall, E. coli persisted longer on plots with crops and were more persisted in the rainy season on all cultivated plots that had received wastewater from the sewage treatment plant until harvest. While in the dry season, it was only detected at harvest on lettuce plots. The E. coli rate increased gradually overtime on the plots that had received water from the watercourse. Aubergine was the only plant that significantly facilitates the vertical migration of E. coli to the water table. On the whole, crops favored the persistence of E. coli on the soil surface and therefore increase the health risk related to the use of wastewater in agriculture.

Managed honeybees and South American bumblebees exhibit complementary foraging patterns in highbush blueberry

Despite Apis mellifera being the most widely managed pollinator to enhance crop production, they are not the most suitable species for highbush blueberries, which possess restrictive floral morphology and require buzz-pollination. Thus, the South American bumblebee Bombus pauloensis is increasingly managed as an alternative species in this crop alongside honeybees. Herein, we evaluated the foraging patterns of the two species, concerning the potential pollen transfer between two blueberry co-blooming cultivars grown under open high tunnels during two seasons considering different colony densities. Both managed pollinators showed different foraging patterns, influenced by the cultivar identity which varied in their floral morphology and nectar production. Our results demonstrate that both species are efficient foragers on highbush blueberry and further suggest that they contribute positively to its pollination in complementary ways: while bumblebees were more effective at the individual level (visited more flowers and carried more pollen), the greater densities of honeybee foragers overcame the difficulties imposed by the flower morphology, irrespective of the stocking rate. This study supports the addition of managed native bumblebees alongside honeybees to enhance pollination services and emphasizes the importance of examining behavioural aspects to optimize management practices in pollinator-dependent crops.

Interference of weeds on Barbados gooseberry initial development

ABSTRACT The Barbados gooseberry crop has agricultural potential, but little information is available regarding cropping practices. More information on weed interference in Barbados gooseberry will support growers to take weed management decisions. The objective of this work was to study initial growth and development of Barbados gooseberry under the interference of weeds. The experiment was conducted in a completely randomized design, with five treatments, composed of Barbados gooseberry in competition with four weed species: slender amaranth (Amaranthus viridis), hairy beggarticks (Bidens pilosa), Benghal dayflower (Commelina benghalensis), purple nutsedge (Cyperus rotundus), and a weed-free control, with six replicates. Weed competition led to a decrease in growth and development of Barbados gooseberry reflected in a reduction of up to 40% in yield and 23% in protein content. Additional work must be conducted evaluating these findings under field conditions, using different seedling production and planting techniques potentially affecting these results.