Orchard Floor Management Research Articles

Orchard floor management practices in arid and semi-arid fruit crops for quality yield

Orchard floor management practices in arid and semi-arid fruit crops for quality yield

Organic orchard floor management in peach: effects on arthropods and associated fruit injury in the Intermountain West.

Understanding orchard floor management is critical to organic tree-fruit production systems given its impact on weeds, soil fertility, tree health, and crop yield. Several viable options are available to producers for weed management and promotion of organic fertility, including use of turf and broadleaf alleyway covers and living and nonliving tree-row mulches. While these measures can be effective, little is known about how these strategies influence arthropod pests, which cause fruit injury. Here, we assessed 6 organic orchard floor management strategies for their impact on arthropod abundance and diversity in an organic peach production system in northern Utah from 2010 to 2014, using sweep netting and pitfall collections along with observed peach fruit damage. Generally, we found that alleyway and tree-row treatments had no impact on total arthropod diversity, species richness, or community diversity. However, earwig (Forficula auricularia) abundance was significantly impacted by alleyway and tree-row treatments that resulted in increased fruit injury. Trefoil alleyway treatments consistently increased earwig abundance across life-history stages, while mulch or Alyssum (straw) tree-row treatments harbored more earwigs and, as a result, increased earwig fruit injury. Since earwigs are especially prone to damaging young, developing fruits, it is imperative that more work is done to assess earwig abundances and life-history traits. Our results demonstrate that detrimental arthropods are sensitive to orchard floor management and can further inform integrated pest management approaches that complement sustainability goals.

Mulching as alternative orchard floor management in apple orchards positively affects water availability and weed control

Mulching as alternative orchard floor management in apple orchards positively affects water availability and weed control

Diversity of Summer Weed Communities in Response to Different Plum Orchard Floor Management in-Row

The effect of five methods of in-row weed management on the species composition and diversity of summer weed communities in a plum orchard was evaluated. Different methods of orchard floor management (OFM) were implemented for seven consecutive years from 2009 to 2015. Festuca rubra L. ssp. rubra–rhizomatous perennial grass was sown as a cover crop in the alleys of the orchard, in the tree planting year. In the seventh year of OFM implementation, the treatments were ranked according to the decreasing value of the Shannon–Wiener floristic diversity index as follows: tillage, post-emergence herbicides spraying, mowing, mulch, and weedy control. The highest value of Simpson dominance index was found in the control treatment. In plots with such treatments as control, mowing, tillage, and mulch, the dominant species was F. rubra. This meant that the rhizomatous cover crop from the alleys penetrated and affected the in-row flora. Vegetation of mulched plots was characterized by low value of density and soil cover. The obtained results indicated that the flora developing in the control, sprayed with post-emergence herbicides, tilled and mowed plots had greater potential to provide ecosystem services, than the flora of mulched plots.

Performance of Sweet Cherry Cultivars and Advanced Selections on Gisela 5 Rootstock in Young Orchards.

Six sweet cherry cultivars and two advanced selections of Gisela 5 rootstock were tested in 2015-2021 at the Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry. Fruit trees were planted at distances of 4.5 × 2.5 m and trained as spindles. Orchard floor management included frequently mown grass in alleyways with herbicide strips along tree rows. Cultivars 'Mindaugė' and 'Irema BS' were the most vigorous at the end of the seventh leaf. Their trunk diameter achieved 11.6 cm. The 'Merchant' cultivar had the smallest trunk diameter-9.3 cm. The average yield in 2018-2021 ranged from 2.75 t/ha for 'Vega' to 8.73 t/ha for 'Regina'. Cultivars 'Regina', 'Sunburst', 'Irema BS' and 'Merchant' had the highest cumulative yield efficiency of 0.440-0.503 kg/cm2 with respect to the trunk cross-section area (TCSA). The least productive cultivar 'Vega' produced fruits of the highest average weight-9.9 g. Fruits of 'Regina' and 'Sunburst' were large as well-8.8-9.1 g. 'Irema BS' fruits had the highest soluble solids content (SSC)-20.2%. The lowest SSC was recorded in 'Merchant' and 'Sunburst' fruits-14.7-15.8%. The yield of advanced selection, No. 102, equaled to the yield of cv. 'Regina'. No. 102 had a high fruit weight, and fruits were distinguished by attractiveness and taste.

Weed management in kinnow mandarin (Citrus nobilis × Citrus deliciosa) orchards using various orchard floor management practices in sub-mountainous region of Punjab, India

Weed management in kinnow mandarin (Citrus nobilis × Citrus deliciosa) orchards using various orchard floor management practices in sub-mountainous region of Punjab, India

Living grass mulching improves soil enzyme activities through enhanced available nutrients in citrus orchards in subtropical China.

Living grass mulching (LGM) is an important orchard floor management that has been applied worldwide. Although LGM can effectively enhance soil nutrient availability and fertility, its effects on microbial-mediated soil nutrient cycling and main drivers are unclear. Meanwhile, the variation of enzyme activities and soil nutrient availability with LGM duration have been rarely studied. This study aims to explore the effects of mulching age and soil layer on enzyme activities and soil nutrients in citrus orchards. In this study, three LGM (Vicia villosa) treatments were applied, i.e., mulching for eight years, mulching for four years, and no mulching (clean tillage). Their effects on the enzyme activities and soil nutrients were analyzed in different soil layers of citrus orchards in subtropical China, i.e., 0-10, 10-20, and 20-40cm. Compared to clean tillage, mulching for four years had fewer effects on enzyme activities and soil nutrients. In contrast, mulching for eight years significantly increased available nitrogen (N), phosphorus (P) nutrients, β-glucosidase, and cellobiohydrolase activities in the soil layer of 0-20cm. In the soil layer of 0-40cm, microbial biomass carbon (C), N, P, N-acetylglucosaminidase, leucine aminopeptidase, and acid phosphatase activities also increased (P < 0.05). Mulching for eight years significantly promoted C, N, and P-cycling enzyme activities and total enzyme activities by 2.45-6.07, 9.29-54.42, 4.42-7.11, and 5.32-14.91 times, respectively. Redundancy analysis shows that mulching treatments for eight and four years had soil layer-dependent positive effects on soil enzyme activities. Microbial C and P showed the most significant positive correlation with enzyme activities, followed by moisture content, organic C, and available N (P < 0.05). Available nutrients contributed almost 70% to affect enzyme activities significantly and were the main drivers of the enzyme activity variation. In summary, LGM could improve soil enzyme activities by increasing available nutrients. The promotion effect was more significant under mulching for eight years. Therefore, extending mulching age and improving nutrient availability are effective development strategies for sustainable soil management in orchard systems. Our study can provide valuable guidelines for the design and implementation of more sustainable management practices in citrus orchards.

Weed community evolution under diversification managements in a new planted organic apricot orchard

Biodiversity conservation and promotion of agroecology (including organic farming) are focused as priorities by European Commission, as reported in the Biodiversity and Farm to Fork Strategies. In this context, agricultural practices can be considered for their contribution to harnessing ecosystem services to sustain agricultural production, while minimising negative environmental effects. Among these, redesigning agricultural systems through diversification practices can be very promising by exploiting the natural biodiversity in space and time, and connecting farms with natural environments. Being an interface between above and belowground, spontaneous plants (i.e., the weeds) are considered valuable agroecosystem components that, if properly managed, provide ecosystem functions and services, and holding key role for biodiversity conservation within agroecosystems. In this study, we explored the response of spontaneous flora communities in terms of abundance, diversity, and functional traits to different soil and agrobiodiversity management strategies (soil ripping vs reduced tillage at orchard planting, soil tillage vs minimum/no tillage in orchard floor management over 5 years) and cover crop introduction in a new planted organic apricot orchard. Our results showed the strong impact of the planting operation on pre-existing spontaneous flora community structure but a resilient trajectory in the following years in recovering the previous community traits distribution. Interannual variability was the main factor affecting communities. However, the reduced tillage condition showed a conservative trend of the incidence of perennials in the community, while the introduction of cover crops generally decreased species richness and abundance. Understanding the mechanisms by which soil management practices affect weed communities can guide the designing of sustainable agroecosystems, preserving their functionality and biodiversity over time.

The Decay and Fungal Succession of Apples with Bitter Rot Across a Vegetation Diversity Gradient

Bitter rot is a disease of apple caused by fungi in the genus Colletotrichum. Management begins with removal of infected twigs and fruit from tree canopies to reduce overwintering inoculum. Infected apple fruit are usually tossed to the orchard floor, which is generally managed as herbicide-treated weed-free tree rows, separated by grass drive rows. We monitored decay rates and succession of fungi of apple fruit with bitter rot in tree canopies, and on the soil surface in tree rows, grass drive rows, and nearby diverse plant communities. We hypothesized that decay would occur most rapidly within diverse plant communities, which would provide a more diverse array of potential fungal decomposers. Apple fruit in tree canopies became dry and mummified and had more Colletotrichum gene marker copies the following growing season than did fruit on the soil surface. Of the soil-surface samples, those in grass drive rows and diverse plant communities had higher moisture, faster decay rates, and sharper decreases in Colletotrichum gene marker copies than apple fruit in tree rows. Fungal composition across all decaying apple fruit was dominated by yeasts, with higher genus-level richness, diversity, and evenness in fruit from tree canopies than those on the soil surface. In soil-surface apple fruit, we observed clear successional waves of Pichia, Kregervanrija, and [Candida] yeasts, with similar but distinctly diverging fungal composition. Our results show that orchard floor management can influence fungal succession in apple fruit with bitter rot but suggests that bitter rot management should primarily focus on removing infected apple fruit from tree canopies.

Soil temperature and horticultural traits as influenced by mulching materials and orchard floor management practices in ber (Zizypus mauritiana Lamk.)

&#x0D; Different type of mulches viz. paddy straw mulch (PSM), black polythene mulch (BPM), and white polythene mulch (WPM) were spreaded under the canopies of Indian ber (Zizypus mauritiana Lamk.) trees in second fortnight of October. The treatments of inter-cultivation (IC) and chemical weed management (CWM), and control trees were also kept for comparative analysis. The daily soil temperature recorded at 0900, 1200, 1400 and 1700 hours from October to April months during 2018-19 and 2019-20 revealed significant variations under different treatments. The respective soil temperature variation during 1st and 2nd year was minimum (9.2 and 9.9 oC) under PSM as compared to 16.5 oC in control plots throughout the investigation period. The soil temperature under PSM was higher during extreme winters whereas, it was comparatively lower during pre and post-winter season as compared to other treatments.The variations in intra-day average soil temperature during the months of October-November and again in March-April was higher than in December-February; the period of extreme winters. Significant reduction in physiological fruit drop was recorded under all the treatments with minimum fruit drop under PSM followed by BPM, while it was maximum in control trees. Likewise, fruit weight and fruit yield was also recorded highest under PSM followed by BPM treatments. The microbes in the rhizopshere of mulched trees with PSM followed by BPM exhibited highest and sustained activity from from Otober to April month under North-West Indian conditions.&#x0D;

MACROELEMENTS CONCENTRATION IN PLUM TREE LEAVES AND SOIL IN RESPONSE TO ORCHARD FLOOR MANAGEMENT

The aim of the study was to determine the influence of various methods of orchard floor management on extractable mactronutrients concentration in plum leaves and orchard soil. Study carried out between 2013 and 2015. Standard mineral fertilization on experimental plots was applied. Trees of ‘Valjevka’ plum (Prunus domestica L.), grafted onto Myrobalan seedlings (Prunus cerasifera Ehrh. var. divaricata Ledeb.), were planted in the spring of 2008. From 2009 to 2015, the following methods of soil cultivation under tree canopies were introduced: control with limited weeding around tree trunks; spraying with foliar herbicides; mulching with organic waste, i.e. straw with compost; mechanical soil cultivation with the use of rotary cultivators and hoe; weed mowing. The method of soil cultivation had influence on leaf concentration of phosphorus, potassium, magnesium and calcium, as well as soil concentration content of phosphorus, potassium, and magnesium in particular years of the study or as three-year mean. Orchard floor management did not affect leaf nitrogen concentration in any way. The results showed that regular weed control in the evaluated type of orchard is not necessary for properly supplying plum trees with macronutrients.

A Review of Potassium-Rich Crop Residues Used as Organic Matter Amendments in Tree Crop Agroecosystems

Ecosystem-based approaches to nutrient management are needed to satisfy crop nutrient requirements while minimizing environmental impacts of fertilizer use. Applying crop residues as soil amendments can provide essential crop nutrient inputs from organic sources while improving nutrient retention, soil health, water conservation, and crop performance. Tree crop hulls, husks, and shells have been found to contain high concentrations of potassium across species including almond, cacao, coffee, pecan, and hazelnut. The objective of this review is to characterize organic sources of potassium focusing on lignocellulosic pericarps and discuss reported effects of surface application on potassium cycling, water dynamics, soil functionality, and crop yield. Research indicates potassium ions solubilize readily from plant material into soil solution due to potassium’s high mobility as a predominately unbound monatomic cation in plant tissues. Studies evaluating tree crop nutshells, field crop residues, and forest ecosystem litter layers indicate this process of potassium release is driven primarily by water and is not strongly limited by decomposition. Research suggests orchard floor management practices can be tailored to maximize the soil and plant benefits provided by this practice. Contextual factors influencing practice adoption and areas for future study are discussed.

Orchard floor management effect on soil free-living nematode communities

Context Although both plant cover and mulch are considered for erosion control in arid and semi-arid regions, they have divergent impacts on soil ecology. Aim We examined the effects of orchard floor management practices on the density and diversity of soil free-living nematode communities and relevant soil abiotic properties. Methods Soils were sampled in winter in a citrus orchard in the Sharon region of Israel from plots that for 6 years had been under (1) annual native species; or (2) Avena sativa and Vicia villosa, planted between tree rows; or (3) woodchip mulching along tree rows. There were two control sites: (4) bare soil between tree rows and (5) bare soil along the tree rows (both common practice). Key results Nematode communities and their trophic diversity were significantly impacted by floor management. Significant increases in soil moisture under plant cover, and higher organic matter and water-holding capacity for all covered orchard floors could be related to nematode changes. Shifts in nematode feeding group structure suggest a shift in the type and availability of soil carbon pools. Conclusions There was a strong association between orchard floor management and soil free-living nematode communities, indicating a shift in the soil food-web structure and functionality. Bare soil harboured fewer nematodes, but more complex communities dominated by persisters, while seeded plant cover had a greater nematode abundance dominated by coloniser communities, indicating increased availability of resources. Implications Results reveal the importance of integrating biological information in performance index determinations for improving soil management decisions, suggesting these relationships as sensitive bio-indicators of soil health.

Effect of Living Mulch on Soil Conditions and Morphometrical Indices of Sweet Cherry Trees

In order to maintain natural biocenosis and to create optimal conditions for reproducing soil fertility, it is necessary to keep the soil under living mulch in organic orchards. But the effect of the living mulch on soil properties and biometric indices of trees has not yet been fully investigated. This work aimed at examining the effects of living mulch (compared with standard mechanical cultivation) on soil moisture, soil temperature and biometric indices of sweet cherry trees in the arid conditions of the Southern Steppe of Ukraine. The work was conducted from 2014 to 2019 in the Southern Steppe of Ukraine in Zelene village near the city of Melitopol (46°46’N, 35°17’E). In organic sweet cherry (<i>Prunus avium L./Prunus mahaleb</i>) orchard standard mechanical cultivation (MC) was compared with living mulch - spontaneous vegetation cover (LM). The soil moisture at 20 cm depth was significantly greater under LM (an average of 3,9%), the soil temperatures under LM plots were lower (an average of 1.5°C over 6 years of research), in comparison to MC. It was established that the trunk cross sectional area of sweet cherry trees was significantly reduced under LM - by 1.2-2.1 times. However, LM contributed to an increase in the shoot growth efficiency – by 1.5-2.9 times, compared to MC. The ratio of total leaf area to the trunk cross sectional area was also significantly greater in conditions of LM, since 2015 by 1.3-2.5 times. The weather conditions of the year significantly influenced the formation of the biometric indices of the trees - Year×orchard floor management system interactions were significantly throughout all years of research. Investigated sweet cherry cultivars (Valery Chkalov and Dilemma) respondend to the floor management systems in a similar way – their biometric indices did not differ significantly.

Soil Nitrogen and Weed Biodiversity: An Assessment under Two Orchard Floor Management Practices in a Nitrogen Vulnerable Zone in Italy

Nowadays, understory vegetation along the tree row is considered a vital source of agroecosystem services and functional biodiversity improvement in the fruit orchard. Hence, current orchard floor management systems encourage practicing a more sustainable approach that supports vegetation cover rather than keeping bare soil herbicide use, or tillage. A two-year field trial was conducted using two different ground management techniques; integrated mowing (mower and brush or disc) and herbicide (glyphosate) in two commercial apple and peach orchards in a nitrogen vulnerable zone (NVZ) of the Marche region, Italy. This study aimed to evaluate the effects of these practices on soil N status, weed abundance, percent of soil cover, and dry weed biomass production. Weed management systems had no significant effect on soil organic matter and N availability; however, an improvement was noticed under integrated mowing when compared to the one treated with herbicides. Integrated mowing had a significant effect on species richness, soil coverage, and weed biomass production, which was approximately 2-times higher than in the herbicide-treated plots. The overall results showed that integrated mowing maintained a balance in the soil N status of both orchards, while supporting above-ground weed biodiversity and soil protection.

Orchard Floor Management Affects Tree Functionality, Productivity and Water Consumption of a Late Ripening Peach Orchard under Semi-Arid Conditions

Semi-arid conditions are favorable for the cultivation of late ripening peach cultivars; however, seasonal water scarcity and reduction in soil biological fertility, heightened by improper soil management, are jeopardizing this important sector. In the present two-year study, four soil managements were compared on a late ripening peach orchard: (i) completely tilled (control); (ii) mulched with reusable reflective plastic film; (iii) mulching with a Leguminosae cover-crop flattened after peach fruit set; (iv) completely tilled, supplying the water volumes of the plastic mulched treatment, supposed to be lower than the control. Comparison was performed for soil features, water use, tree functionality, fruit growth, fruit quality, yield and water productivity. Even receiving about 50% of the regular irrigation, reusable reflective mulching reduced water loss and soil carbon over mineralization, not affecting (sometimes increasing) net carbon assimilation, yield, and fruit size and increasing water productivity. The flattening technique should be refined in the last part of the season as in hot and dry areas with clay soils and low organic matter, soil cracking increased water evaporation predisposing the orchard at water stress. The development and implementation of appropriate soil management strategies could be pivotal for making peach production economically and environmentally sustainable.

Integrated Weed Management in High Density Fruit Orchards

Despite the productivity, achieving long-term sustainability and maintaining plant biodiversity have become the pivotal goals in orchard floor management, especially along tree rows. Thus, the paradigm of eradicating weeds in the tree row using chemical herbicide or repeated soil tillage needs to be substituted with more sustainable alternatives. This study was conducted in two commercial apple and peach orchards in Marche region (Italy). Two integrated mechanical approaches, integrated mowing (mower and brush or disc) and integrated tillage (blade weeder and integrated mowing), were compared with the standard herbicide system in a 2-year trial. Weed species diversity, soil coverage, and weed biomass production, including, gas exchange parameters, trunk cross-sectional area (TCSA), fruit yield and quality were measured. Overall, both integrated practices demonstrated approximately 82%, 91% and 113% more species diversity, soil coverage, and weed biomass production, respectively, than herbicide systems. No significant differences were found in terms of tree gas exchange parameters, growth and fruit yield. However, a few fruit quality parameters such as fruit firmness, soluble solids content (SSC) and dry matter content responded positively to the integrated practices. These results suggest that the integrated mechanical approaches of weed management increased orchard biodiversity, and had no adverse effects on tree growth, fruit yield, and quality. The average costs per hectare associated with chemical weed control were 66.5% and 72% lower, respectively, compared to integrated tillage and integrated mowing. However, the government subsidies provided to the orchardists to encourage sustainable management practices were able to offset such additional costs.

Soil microbial and nutrient responses over seven years of organic apple orchard maturation

Seven years of twelve treatment combinations of annual compost, wood chips, shredded paper mulch, or mow-and-blow ground cover and poultry litter, organic commercial, or no fertilizer control surface applications on soil decomposition and microbial activity were evaluated in an organic apple orchard. Because soil amendments were surface applied, microbial biomass, enzyme activities, organic matter, dissolved organic carbon (DOC) and dissolved total nitrogen (N), ammonium-N, and nitrate-N concentrations were measured in March from 2007 to 2013 at 0–0.1 and 0.1–0.3 m soil depths where biochemical activity and nutrient availability were expected to be greatest and where tree roots were expected to be located. Ground covers were applied by volume based on horticulture management and these applications rather than fertilizers were stronger drivers of soil nutrient and microbial property responses. Dehydrogenase and β-glucosaminidase activities were 1.5 times greater in 2008 and 2009, respectively, under mow-and-blow as compared to other ground covers. Enzymes may be sensitive indicators separating living and non-living mulch effects on soil during establishment of fruit tree orchards in the southeastern U.S. Organic matter (OM) and soil water content increased in all ground covers during the study. At greatest differences, soil OM and DOC were more than twice and dissolved total N and nitrate-N were more than three and five times greater in compost than other ground cover treatments. Relative differences between compost and other ground covers did not persist to the same extent during the seven years. Orchard floor management may need different strategies during different stages of orchard development.

Effect of living mulch on physiological and biochemical parameters of cherry leaves and fruits with organic growing technology

In organic sweet cherry (Prunus avium L./Prunus mahaleb) orchard standard mechanical cultivation was compared with living mulch – spontaneous vegetation cover. Since 2013 the experimental orchard has been maintained with two different orchard floor management systems: standard mechanical cultivation (MC) – one discing at a 15 cm depth + manual weeding during the growing season was compared with living mulch (LM) – spontaneous vegetation cover. The natural vegetation of grasses was mowed 4 times during the growing season and the clippings were left on the ground for decomposition. Any other management was identical in each treatment. Synthetic fertilizers and chemical plant protection products were not used. It was established that total moisture content of the leaves was significantly reduced under LM (over 2 years) or did not differ significantly from MC (1 year). The water-retaining ability of the leaves did not differ significantly between LM and MC (2 years) or was higher in the conditions of LM (1 year). The total leaf area at the beginning of the study (1 year) was larger in MC conditions. In the following year, the difference between LM and MC was insignificant. In 2019, the total leaf area was significantly larger in the conditions of LM. An increase in the total leaf area under LM conditions led to a significant decrease in the specific surface density of the leaves, the accumulation of chlorophylls in them, and a decrease in the ratio of chlorophylls (a/b) due to an increase in the content of chlorophyll b (compared to the MC conditions). The difference in fruit size parameters, average weight of the fruits, total soluble solids, total sugars, titratable acidity, sugar-acid index were insignificant between LM and MC. Ascorbic acid and total anthocyanins content of sweet cherry fruit was significantly increased under LM conditions compared to MC. The results show that cherry trees gradually adapt to coexistence with natural herbs and, during stress, accumulate more physiologically active substances in the fruit. Key words: sweet cherry, organic orchard, living mulch, total leaf area, specific leaf density, chlorophylls, fruit size, ascorbic acid, anthocyanins.

Long-term response of groundcover components to organic and conventional weed control in shaded and open-sun coffee in Nicaragua

The weed-free period is employed to evaluate the effectiveness of practices to reduce crop loss to weeds. To orient sustainable cropping system approaches in perennial crops such as coffee which are often grown with trees, orchard floor or groundcover management has been proposed to address not only crop loss, but also soil protection, plant nutrition, habitat for beneficial organisms and labor and input costs. The results of a long-term experiment in Masatepe, Nicaragua, comparing two intensities of organic and conventional coffee management under four combinations of deciduous and evergreen trees either leguminous (Inga laurina and Samanea saman) and non-leguminous (Simarouba glauca and Tabebuia rosea) and full sun concluded that with selective weed management under trees, soil is protected with both low-growing, shallow-rooted cover vegetation and tree leaf litter without yield loss, while also reducing herbicide and labor use. Over 11 years, treatments with trees compared to full sun coffee showed near absence of bare soil (P < .001) and increasing presence of leaf litter (P < .001) and cover vegetation (P < .001), especially in the first 8 years. Selective control, either herbicide or manual, resulted in minimal bare soil, a declining area covered by weeds and increased area, from 40 to 70%, under cover vegetation. Selective control with herbicides had less weedy vegetation than manual selective control. Trees compared to full sun showed increased accumulation of whole leaf and fractionated leaf layers measured in the dry season with treatments including Inga laurina greater than other tree treatments. Labor and herbicide costs declined with increasing time under trees (P < .001), while selective control reduced herbicide use with higher labor costs. A regression of groundcover components on coffee berry yields explained less than 10% of variability. Two research priorities are identified to increase the contribution of groundcover components to sustainable coffee systems – 1) cover vegetation species and management in water conservation and use and 2) the role of tree species and their litter on water, soil biology dynamics and O horizon formation.