Practicing Mechanical Weeding in Orchards
1. Presentation
Characterization of the technique
Description of the technique:
Information originally from the Guide for the design of fruit production systems economical in phytopharmaceutical products (2014) / Technical sheet n°8 - For more information See link
Principle:
This is a physical control method against weeds by mechanical weeding. The technique consists of passing on each side of the row to remove the weeds as close as possible to the trees using mechanical tools. It is a substitution technique for the use of glyphosate to weed the row.
Soil working tools such as hydraulic rotary tools, blades, discs, rotary hoes or non-soil-working tools for superficial scraping such as brushes or wires can be used.
Details on the technique:
The quality of the work depends on the tool, working speed, development stage of the weeds, soil condition (moisture, texture, absence of ruts…).
The forward speed between 2 and 7 km/h depends on the density, stage of the weeds and the device used.
This method requires significant technical skill (mastery of the tractor and the tool) to avoid damaging or even uprooting the trees, as well as observations of the regrowth of the weed flora.
The irrigation system must be compatible (suspended or buried).
Some tools are not compatible with trees on mounds.
Some tools cannot be used in young orchards due to risk of trunk or root damage…
Implementation period
Spatial scale of implementation Plot
Application of the technique to...
All crops: Easily generalizable
Easily generalizable
This technique can be applied to most fruit species.
However, in cider orchards, where harvesting is done on the ground, soil working is no longer possible once the orchard has entered its production phase (fruits harvested). Indeed, the soil must be firm and as flat as possible to facilitate mechanical harvesting.
Mechanical weeding indeed promotes the formation of ruts and increases the risk of harvesting fruits in muddy soil conditions.
All soil types: Generalization sometimes delicate
Generalization sometimes delicate
For the technique to be effective, it is important to have a soil that is not very stony and well-drained.
Mechanical weeding with soil-working tools increases the risk of erosion on sloping soils.
Regulation
The acquisition of mechanical weeding tools for perennial crops is subject to a CEPP sheet (action n°54 : Weed perennial crops using a mechanical weeding tool).
2. Services provided by the technique
3. Effects on the sustainability of the cropping system
"Environmental" criteria
Effect on air quality: Increasing
phytosanitary emissions: DECREASE
Effect on water quality: Increasing
pesticides: DECREASE
Effect on fossil resource consumption: Variable
fossil energy consumption: VARIABLE
Other: No effect (neutral)
Comments
This method allows replacing or reducing the use of chemical herbicides.
With soil-working tools, the technique allows water savings in dry climates.
"Agronomic" criteria
Productivity: Variable
Variable
Mechanical weeding avoids phytotoxicity problems induced by chemical herbicides on young orchards.
Some non-soil-working tools (wires) help limit ivy,
suckers, shoots (hazel…) or perform vine pruning.
Some soil-working tools favor plants with easy propagation (for example discs and rotary tools favoring couch grass).
Switching to mechanical weeding, with soil-working tools, in established orchards leads to destruction of superficial roots and can temporarily reduce tree nutrition and yield on adult trees.
Soil fertility: Variable
Variable
Mechanical weeding with soil-working tools leads to soil depletion in organic matter.
Mechanical weeding with soil-working tools can reduce structural problems in soils with high crusting index, but if done under poor conditions (non-drained soil), it can promote structural accidents (compaction, plow pan, crusting…).
"Economic" criteria
Mechanization costs: Increasing
Increasing
Investment cost from €7,000 to €12,000 depending on the tool (2014 price)
"Social" criteria
Working time: Variable
Variable
The technique requires significant working time (main cost factor compared to equipment investment). However, mechanical weeding with soil-working tools allows coupling with incorporation of organic amendments, mulching, grass mowing...
4. Favored or disadvantaged organisms
Favored Bioagressors
| Organism | Impact of the technique | Type | Details |
|---|---|---|---|
| Woolly apple aphid (Eriosoma lanigerum) | pest, predator or parasite | Risk of wounds on the trunk or roots can be entry points for some bioagressors (e.g., spread of verticillium wilt, canker formation, bacterial diseases, woolly aphids…) | |
| Verticillium wilt | pathogen (bioagressor) | Risk of wounds on the trunk or roots can be entry points for some bioagressors (e.g., spread of verticillium wilt, canker formation, bacterial diseases, woolly aphids…) | |
| bacterial canker | pathogen (bioagressor) | Risk of wounds on the trunk or roots can be entry points for some bioagressors (e.g., spread of verticillium wilt, canker formation, bacterial diseases, woolly aphids…) |
Disadvantaged bioagressors
| Organism | Impact of the technique | Type | Details |
|---|---|---|---|
| weeds | STRONG | weeds | This method is a main lever to control weeds. |
| vole | pest, predator or parasite | Mechanical weeding disturbs voles by destroying superficial galleries and herbaceous cover (favoring predation). However, this is not always sufficient to control voles. |
Favored Auxiliaries
| Organism | Impact of the technique | Type | Details |
|---|
Disadvantaged auxiliaries
| Organism | Impact of the technique | Type | Details |
|---|---|---|---|
| Predatory and granivorous ground beetles | Natural enemies of bioagressors | If mechanical weeding is done (with soil-working tools) often and/or under poor conditions, there may be risks of destruction of some auxiliaries (e.g., ground beetles). |
Favored climatic and physiological accidents
| Organism | Impact of the technique | Details |
|---|
Disadvantaged climatic and physiological accidents
| Organism | Impact of the technique | Details |
|---|
5. For more information
- Alternatives to chemical weeding of fruit trees. In: Guide to reasoned and organic protection in Languedoc-Roussillon
- -Regional Chamber of Agriculture Languedoc-Roussillon
Technical brochure, 2013
SudArbo collection
- CTO Olive productions in organic agriculture
- -Afidol, Aix-en-Provence
Technical brochure, 2012
Afidol guides collection, 52-58
- Choosing your inter-row tool, row maintenance in viticulture and arboriculture
- -Chamber of Agriculture of Hérault
Technical brochure
- Comparison of hoes in organic fruit crops
- -Irla E., Gut D., Weibel F.
Technical brochure, 2002
FAT Reports, 581, Ettenhausen, Switzerland, 1-8.
- Soil management dossier in OA. Alternatives to soil working on the row and soil management in arboriculture
- -Garcin A., Bussi C., Corroyer N., Dupont N., Ondey S-J., Parveaud C.-E.
Alter Agri, Technical brochure, 2012
Alter Agri, n° 116, 19-21
To access the brochure see link
- Demonstrations of soil working equipment in arboriculture
- -Chamber of Agriculture of Lot-et-Garonne, Chamber of Agriculture of Dordogne
2010
- Mechanical weeding on the row by mowing or hoeing
- -GIS Fruits, Multimedia, 2018
- Experimentation: maintenance of the row in organic arboriculture plantation
- -Chamber of Agriculture of Tarn-et-Garonne
Technical brochure, 2009
- Integrated fruit production guide 2014
- -Regional Chamber of Agriculture Paca, La Pugère Station
2014
Objectifs Info Arbo, 30-32
6. Keywords
Bioagressor control method: Physical control
Mode of action: Catch-up
Type of strategy regarding pesticide use: Substitution
Annexes
S'applique aux cultures suivantes
Favorise les bioagresseurs suivants
Défavorise les bioagresseurs suivants
Défavorise les auxiliaires
