scholarly journals White clover living mulch enhances soil health versus annual cover crops

2021 ◽  
Author(s):  
Nicholas S. Hill ◽  
Matthew Levi ◽  
Nicholas Basinger ◽  
Aaron Thompson ◽  
Miguel Cabrera ◽  
...  
2021 ◽  
pp. 1-28
Author(s):  
Nicholas T. Basinger ◽  
Nicholas S. Hill

Abstract With the increasing focus on herbicide-resistant weeds and the lack of introduction of new modes of action, many producers have turned to annual cover crops as a tool for reducing weed populations. Recent studies have suggested that perennial cover crops such as white clover could be used as living mulch. However, white clover is slow to establish and is susceptible to competition from winter weeds. Therefore, the objective of this study was to determine clover tolerance and weed control in established stands of white clover to several herbicides. Studies were conducted in the fall and winter of 2018 to 2019 and 2019 to 2020 at the J. Phil Campbell Research and Education Center in Watkinsville, GA, and the Southeast Georgia Research and Education Center in Midville, GA. POST applications of imazethapyr, bentazon, or flumetsulam at low and high rates, or in combination with 2,4-D and 2,4-DB, were applied when clover reached 2 to 3 trifoliate stage. Six weeks after the initial POST application, a sequential application of bentazon and flumetsulam individually, and combinations of 2,4-D, 2,4-DB, and flumetsulam were applied over designated plots. Clover biomass was similar across all treatments except where it was reduced by sequential applications of 2,4-D + 2,4-DB + flumetsulam in the 2019 to 2020 season indicating that most treatments were safe for use on establishing living mulch clover. A single application of flumetsulam at the low rate or a single application of 2,4-D + 2,4-DB provided the greatest control of all weed species while minimizing clover injury when compared to the non-treated check. These herbicide options allow for control of problematic winter weeds during clover establishment, maximizing clover biomass and limiting canopy gaps that would allow for summer weed emergence.


1993 ◽  
Vol 73 (4) ◽  
pp. 481-488 ◽  
Author(s):  
B. J. Zebarth ◽  
S. Freyman ◽  
C. G. Kowalenko

The use of inter-row ground covers has been suggested to reduce soil degradation in raspberry (Rubus idaeus L.) production. The effect after 6 yr of consistent inter-row management of ground covers or roto-tillage in raspberry on soil wet aggregate stability (WAS), bulk density, organic C and total N, and mineralizable nitrogen in the Fraser Valley of British Columbia was studied. Management treatments included no cover crop or cover crops of barley (Hordeum vulgare L.), sheep's fescue (Festuca ovina L.), perennial ryegrass (Lolium perenne L.), and white clover (Trifolium repens L.). A general pattern of perennial grasses > legume and barley > control was observed for soil WAS. Some quantitative and qualitative differences in the organic component of the soil profile to 30 cm were detected among management treatments. The differences were not statistically strong because the changes were small relative to the large pool present, but were relatively consistent overall. The white clover treatment tended to have more organic carbon, particularly in the subsurface, than the other treatments. The four treatments that included inter-row vegetation tended to have a greater amount of total and mineralizable N than the clean-tilled control. Crop vigour, as indicated by cane diameter, was reduced by the perennial grasses, but the inter-row management had only limited effects on berry yield. White clover appears to provide the best compromise between improving soil quality and minimizing competition with the berry crop. Key words: Wet aggregate stability, barley, sheep's fescue, perennial ryegrass, white clover


2018 ◽  
Vol 34 (5) ◽  
pp. 439-446 ◽  
Author(s):  
David Robb ◽  
Geoff Zehnder ◽  
Robin Kloot ◽  
William Bridges ◽  
Dara Park

AbstractOrganic vegetable growers rely heavily on mechanical methods such as tillage and other forms of labor-intensive soil cultivation for weed management despite the negative effects to soil health associated with intensive soil disturbance. The use of cover crops and no-till (NT) vegetable production represents an alternative approach to weed control that can enhance rather than degrade soil health; however, there are challenges inherent with this practice and previous results in vegetable production have been mixed. Field experiments were conducted over 2 yr at the Clemson Student Organic Farm to examine the effects of tillage [NT versus conventional tillage (CT)] on weed development and management in organic tomato and summer squash production under different nitrogen (N) fertility regimes, and to assess soil N dynamics in both systems. Squash yields were similar between tillage treatments in both years. NT tomato yields were 43% greater than CT yields in 2014, whereas CT tomato yields were 46% greater than NT yields in 2015. Squash and tomato yields per unit of management labor (time) were significantly greater in NT compared with CT treatments for both years. There were no statistical differences in squash and tomato yields between N fertilization treatments in either year. Pre- and post-season soil N results were mixed. Pre-season soil N levels were significantly higher in NT tomato plots in 2014 but similar between tillage treatments in tomato plots in 2015 and in squash plots both years. Post-season soil N levels in tomato plots were similar between tillage treatments both years. Post-season soil N levels were significantly higher in NT squash plots in 2014 and in CT squash plots in 2015. Roller-crimped NT mulches provided adequate early-season weed suppression in both years and saved considerable weed management and seedbed preparation labor. Overall, the results demonstrated that organic NT is a viable method for reduced tillage summer vegetable production in the southeastern Piedmont region.


Agronomy ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 70
Author(s):  
Terry J. Rose ◽  
Lee J. Kearney

Nitrogen (N) fertiliser is applied to perennial horticultural crops to increase yields, but subsequent N losses in subtropical plantations may be high due to intense rainfall and warmer temperatures. While legume cover crops could potentially contribute N to the tree crops and reduce fertiliser-N requirements, few studies have quantified potential fixed-N inputs from cover crops legumes in tropical or subtropical tree crop systems. To address this, we investigated growth and N fixation of summer-growing Pinto peanut (Arachis pintoi Krapov. & W. C. Greg cv. Amarillo) and winter/spring dominant white clover (Trifolium repens L. cv. Haifa) grown as a mixed species cover crop in two commercial subtropical avocado (Persea americana Mill. cv. Hass) plantations. Legume biomass was assessed prior to mowing of the inter-row (fortnightly in summer and every 6–8 weeks over winter) and N fixation was estimated using the 15N natural abundance technique. Biomass production was 7377 kg ha−1 (930 kg ha−1 for white clover and 6447 kg ha−1 for Pinto peanut) at the first site over the 14-month period from December 2014 to January 2016, and 4467 kg ha−1 (1114 kg ha−1 for white clover and 3353 kg ha−1 for Pinto peanut) at the second site over the same period. Estimation of N fixation was not possible at the first site, due to a lack of difference in isotopic discrimination between the legume shoots and the reference plant (kikuyu (Pennisetum clandestinum Chiov.)) material. While legume shoots accumulated 157 kg N ha−1 (38 kg ha−1 for white clover and 119 kg ha−1 for Pinto peanut) across the season at site 1, the % N derived from atmosphere (%Ndfa) in legumes was relatively low (50–60% in Pinto peanut during the warmer months and around 30% in autumn and early spring, and from 13 % in April to 69% in September for white clover). The low %Ndfa in the legumes may have been due to low rainfall or molybdenum (Mo) deficiency. Ultimately the legume cover crops contributed an estimated 50 kg fixed N ha−1, which could partially offset fertiliser N requirements of the tree crop. Our results demonstrate the need to quantify N fixation in legume cover crops to assess potential N benefits as opposed to relying on typical measurements of legume biomass and N accumulation.


Agriculture ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 372
Author(s):  
Lucas Clay ◽  
Katharine Perkins ◽  
Marzieh Motallebi ◽  
Alejandro Plastina ◽  
Bhupinder Singh Farmaha

Cover crops are becoming more accepted as a viable best management practice because of their ability to provide important environmental and soil health benefits. Because of these benefits, many land managers are strongly encouraging the use of cover crops. Additionally, there is limited information on farmers′ perceptions of the benefits and challenges of implementing cover crops. Many farmers state that they do not have enough money or time to implement cover crops. In an attempt to gather more data about the adoption rate and perceptions of cover crops in South Carolina, a survey was sent to 3000 row crop farmers across the state. Farmers were asked whether they implement cover crops and their perceptions of the benefits and challenges associated with implementation. Furthermore, questions were asked regarding the impact of row cropping on their environment to gauge farmer′s education level on environmental impacts. Responses showed many people are implementing cover crops; however, there are still differences in perceptions about benefits and challenges between those who are adopting cover crops and those who are not. This research assesses these differences and aims to provide a baseline for focusing cover crop programs to tackle these certain challenges and promote the benefits.


2016 ◽  
Author(s):  
Georgina Key ◽  
Mike G. Whitfield ◽  
Julia Cooper ◽  
Franciska T. De Vries ◽  
Martin Collison ◽  
...  

Abstract. The goal of this study is to clarify research needs and identify effective actions for enhancing soil health. This was done by a synopsis of soil literature that specifically tests actions designed to maintain or enhance elements of soil health. Using an expert panel of soil scientists and practitioners, we then assessed the evidence in the soil synopsis to highlight actions beneficial to soil health, actions considered detrimental, and actions that need further investigation. Only seven of the 27 reviewed actions were considered to be beneficial, or likely to be beneficial in enhancing soil health. These included the use of a mixture of organic and inorganic soil amendments, cover crops, crop rotations, and growth of crops between crop rows or underneath the main crop, and the use of formulated chemical compounds (such as nitrification inhibitors), the control of traffic and traffic timing, and reducing grazing intensity. Using a partial Spearman's correlation to analyse the panel's responses, we found that increased certainty in scientific evidence led to actions being considered to be more effective due to them being empirically justified. This suggests that for actions to be considered effective and put into practice, a substantial body of research is needed to support the effectiveness of the action. This is further supported by the high proportion of actions (33 %), such as changing the timing of ploughing or amending the soil with crops grown as green manures, that experts felt had unknown effectiveness, usually due to insufficient robust evidence. Our assessment, which uses the Delphi technique, increasingly used to improve decision-making in conservation and agricultural policy, identified actions that can be put into practice to benefit soil health. Moreover, it has enabled us to identify actions that need further research, and a need for increased communication between researchers, policy-makers and practitioners, in order to find effective means of enhancing soil health.


1993 ◽  
Vol 8 (2) ◽  
pp. 51-56 ◽  
Author(s):  
Albert Fischer ◽  
Larry Burrill

AbstractLiving mulches are vegetative covers that can be grown in association with row crops to reduce soil erosion, improve trafficability and suppress weeds. Interference by the living mulch can reduce yields of an associated crop. The interference between a white clover (Trifolium repens L. ‘New Zealand’) living mulch and sweet corn (Zea mays L. ‘Golden Jubilee’) was studied using an established clover sward that was mowed and then sprayed with 1 to 1.5 kg ai/ha of atrazine. Corn was planted at different densities and planting arrangements into a narrow band tilled in the clover. Interference by clover reduced corn yields by 12 to 39%. However, when corn row width was reduced from 0.76 to 0.38 m, competition among corn plants declined; they became more vigorous and clover- suppress ive and reached even higher yields than conventional (no mulch) corn in 0.76 m rows. Similarly, sweet corn planted at a range of densities into a clover mulch killed by atrazine yielded more in equidistant planting than in wide (0.76 m) rows. A near equidistant corn planting arrangement can be a low-input alternative to achieve season-long clover suppression and thus minimize clover's competition with the intercropped corn.


Sign in / Sign up

Export Citation Format

Share Document