Woven tarps in rows, alternatives to weeding
Context
- Farmer's name: Franck CORGIAT
- Farm name: EARL MAS CAGNARD Department: Bouches du Rhône
- Total UAA: 12.5 ha
Main workshops: Arboriculture workshop
Species of the SdC DEPHY: Peach tree: 6.40 ha
Species #2: Apricot 0.12 ha
Species #3: Apple tree 5.93 ha Species/varieties/Appellations: Peaches and yellow and white nectarines (early, season and late) - Marketing channel: Wholesalers, retailers and farm sales
- Other workshops: None
- Workforce: One permanent and seasonal workers as needed
- Certification/Label: Apple workshop in OF
- Yield objective: Between 20 and 40 tons/ha Other context elements: Orchard trained in palmette 4.5 m x 2 m, irrigation by micro-sprinkler. Practices scarification on inter-rows. Orchard in peri-urban area.
- Key system elements: Deep soil filtering and slightly compacted, alluvium of the Durance. Orchard under hail net, irrigated.
- Practice within the cropping system: Intensive IFP, unmown cover crop (beneficials), control of hydromineral nutrition, absence of herbicide linked to this practice strengthens the cropping system.
- Target Pests and diseases: Weeds
- Origin of the practice and farmer's path
- Weed control is essential for the good development of the orchard, especially in the juvenile phase. The alternatives to chemical weeding that were proposed to me did not satisfy me (soil work): machine investment, slow work… In connection with my technical service and the farm network, this solution of woven ground covers (similar to practices in gardening and green spaces) was discussed by the group and appealed to me. After some trials with several producers in the network and a cost evaluation, we launched it. Today this technique is an integral part of the technical itinerary.
The technique
Objective
- Effectively control weeds without increasing mechanized labor time and limit their competition.
- Avoid injuries to trunks and roots (verticillium wilt) by mechanical weeding.
- Reduce water inputs by less evaporation under the cover.
- Improve soil warming in spring: essential aspect in stone fruits to meet nitrogen needs.
- Anticipate the stop and/or reduction of herbicides.
Description
- Installation of a black woven ground cover of 130g/m2 on the row, after or before planting.
- Ideally, the outer edge of the cover will be buried in the soil about 20 cm deep, otherwise held with metal staples.
- Ensure a perfect soil preparation to limit possible pockets under the cover, pockets that can fill with plant debris and serve as a seedbed for weed emergence on the cover.
- Likewise, stretch the cover during installation to avoid these pockets.
- If drip irrigation is used, pipes will be laid under the cover.
Start date of implementation
Winter 2013
Farmer's expectations
Concerned about his environmental impact, aware of the impact of herbicides on water quality, Franck wanted to find an alternative to chemical weeding. It had to be compatible with OF, effective and least labor-intensive for him.
Advantages and limitations
Advantages
- Total or largely elimination of herbicide IFT reduction.
- Undeniable effectiveness and risk-free on young orchards.
- Water savings.
- Improves soil warming.
- Growth dynamics and establishment of the young orchard optimized.
- Improves water penetration into the soil compared to chemically weeded soil.
Limitations
- Particular caution if presence of vole. To be avoided in apple tree.
- In too stony situations, very delicate implementation.
- Vigilance on risk of over-irrigation.
- Requires fertigation, delicate in OF (cost: 20 euro per unit of nitrogen).
- Maintenance of the cover necessary to ensure its longevity.
- Delicate management of the cover edge/start of cover crop.
Implementation and success conditions
- Carry out planting and prune the scions, being as careful as possible about leveling the soil near the tree.
- Install the irrigation system (drip or micro-jet).
- Mark out with a plow two furrows about 20 cm deep in which the edges of the cover will be inserted.
- Install the cover: it requires 5 people: 2 who unroll the cover over the trees, 1 who walks on the cover and cuts it with a cutter at the tree, and 2 others who cover the cover edges with soil using shovels to block it. Then, the tractor driver covers the buried part of the cover edge with discs or shares.
- Roll over the buried part to finalize the installation.
Farmer's testimony
"At first, we used metal staples to fix the cover to the ground. On Mistral days after installation, it was often lifted and the work had to be redone. Today, we prefer to bury it to avoid this, even if it takes a little longer. Other producers in the DEPHY network share this practice and we all make the same observation. Regarding the cost of the technique, it will vary depending on your planting distances (number of rows per ha) and the width of the cover used. You should count about €2,500 for the cover, €600 for installation (50 hours/ha) at setup and plan 6 h/ha annually for maintenance."
Farmer's advice: "Be careful during installation. You can let the cover crop grow between rows without problems, which is a guarantee of biodiversity. Watch out for voles. Be careful with irrigation and take care of your cover as you would any tool."
Improvements or other uses considered
At first, green or brown covers of the same grammage per m2 (130g) were tested, but these were failures due to their too short lifespan. Some producers have equipped themselves with rotary brushes to mechanize cover maintenance: they pass once or twice a year to clean the cover and manage the edge. Currently, this practice is developing in peach, apricot tree, cherry tree, almond tree and pear tree.
Results
Result indicators
| Initial | 2017 | 2018 | 2019 | |
|---|---|---|---|---|
| Weed control | 
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| Chemical herbicide IFT | 1.5 | 0 | 0 | 0 |
| Yield | Between 20 and 40 t/ha | No impact
on yield (between 20 and 40 t/ha) |
No impact
on yield (between 20 and 40 t/ha) |
No impact
on yield (between 20 and 40 t/ha) |
| Observation time |
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| Mechanization costs |
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| Working time in the plot |
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Farmer's takeaway
"Once established, this practice is comfortable and effective. The vole issue and its management must be carefully considered."
DEPHY network engineer's opinion
Herbicides certainly do not account for much of the total IFT, but can be responsible for diffuse pollution of surface and groundwater and at the same time alter proper soil functioning (compaction at the tree base for example). Working towards and planning the elimination of herbicides are important axes and producers' concerns on the subject are clear. The practice addresses these current and future challenges. It is one solution among others, with known advantages and disadvantages. Currently, this practice is developing within the DEPHY network and beyond. It is also good that the technique is adapted to the vole issue. For clarity, the farmer's dissatisfaction regarding mechanization costs and working time in the plot in 2017 is linked to the cover installation that year.
Sources and references
Ecophyto DEPHY, 2021, Remarkable practices of the DEPHY network: Woven ground covers on the row, alternatives to weeding. Available at: https://ecophytopic.fr/sites/default/files/2021-04/PRATIQUE_70GR13AR_Arboriculture_PACA.pdf
