Controlling Voles by Installing an Exclusion or Protective Mesh
1. Presentation
Characterization of the technique
Description of the technique:
Information originally from the Guide for the design of fruit production systems sparing phytosanitary products (2014) / Technical sheet no. 20. For more information See link
Principle:
Physical control method against voles by installing a barrier (at the edges of plots or around trees) to prevent voles from attacking the root system. This technique is also valid for other bioagressors: cervids, rabbits, beavers…
This control method is based on two principles:
- The exclusion mesh: this involves placing a metal mesh with a surface part and a buried part, preferably before planting, around the plots to prevent voles and other pests from entering the plot. These barriers lead pests to follow the obstacle and direct them towards traps positioned along the fence. For this, it is recommended to place release traps for predators outside the mesh and traps (guillotine or clamp type) inside the plot to anticipate entry.
- The protective mesh: This is either a mesh installed before planting that surrounds the root system of trees to prevent voles from attacking it; or a mesh/sleeve protecting the trunk against rabbits, hares, and beavers.
Example of implementation:
Practical application of the technique:
– Exclusion mesh against the vole: about 50 cm high, buried at least 40-50 cm deep, especially for the field vole which can dig down several tens of centimeters depending on the arable soil (if this species of vole is not present, about twenty centimeters depth may suffice), with a 10 cm flap turned outward.
– Non-lethal traps every 20-25 m outside (and ideally also inside) the plot along the mesh (10 cm from the mesh) of the release trap type (opening roof) for predators (e.g., Standby® trap).
– Fixing on iron stakes (type for reinforced concrete) every 10 m (if necessary, provide reinforcement with slats every 3 to 5 m) to prevent mesh sagging
– Exclusion mesh against cervids: 2 m high and surrounding the plot
– Protective mesh/sleeve: mesh size adapted to the target bio-aggressor (vole, rabbit, deer…)
Protections can be implemented at planting time:
– Meshes around roots for voles (galvanized iron mesh, 13 mm mesh size, 50 cm high). Make a cylinder 25-30 cm in diameter around the trunk, fold the mesh at the bottom and place the mesh in the planting hole, then place the tree with soil and finally fold the mesh above.
– Others: metal grids or rods around the trunk against cervids, plastic sleeves at the base of the trunk against rabbits and hares.
Details on the technique:
For the technique to be effective, it is important to "empty" the population present in the orchard, preferably before installing the mesh.
It is also necessary to maintain monitoring and possibly implement complementary control with other techniques inside the protected area (mechanical traps). At the same time, it is strongly advised to maintain a well-weeded ground surface between the trap and the mesh (or place bases under the traps) to increase the effectiveness of trapping.
It is also important to engage in a collective control approach (organized under the aegis of a sanitary organization (OVS) for the plant domain such as the Regional Federation of groups for defense against harmful organisms - Fredon) and in combination with other control methods to limit pressure around the plot.
This technique also requires monitoring which will be ensured by:
– Training on recognition of target and non-target species, precautions to take
– Regular inspection and maintenance of the mesh and traps to avoid trapping non-target species or predators that may enter traps (e.g., weasel, ermine)
– Observations of mounds in the orchard and mechanical trapping (guillotine or clamp traps) inside the mesh to eliminate remaining individuals and prevent recolonization
– Regular maintenance (mowing or weeding) along the mesh (for trap effectiveness)
Implementation period On established crops
Spatial scale of implementation Plot
Farm
Territory
Application of the technique to...
All crops: Easily generalizable
Easily generalizable
The technique can be applied to all fruit species
All soil types: Easily generalizable
All climatic contexts: Easily generalizable
Regulation
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
Other: No effect (neutral)
This technique is an environmentally and human-safe lever for protecting crops. Chemical control, on the other hand, presents significant risks for the food chain and domestic animals by ingestion of poisoned animals and to a lesser extent by consumption of poisoned baits. It is prohibited in case of high populations.
"Agronomic" criteria
Productivity: No effect (neutral)
No effect
But beware of the risk of root strangulation with the protective mesh against voles
Production quality: No effect (neutral)
No effect (neutral)
Functional Biodiversity: Increasing
Release traps favor the presence of predators on the plot (fox, cat,
ermine, etc.) that consume voles in the release traps (Standby type) or
along the barrier.
Do not place traps too close to the meshes to avoid trapping frogs and
toads.
NB: chemical control presents significant risks for the food chain and domestic animals by ingestion of poisoned animals and to a lesser extent by consumption of poisoned baits. It is prohibited in case of high populations.
"Economic" criteria
Operational costs: Increasing
Increasing
Exclusion mesh (voles):
High cost for large plots: €2 - 4 per linear meter excluding labor (€10 - 12 per linear square meter including installation) but minimum mesh lifespan of 5 years.
Standby trap cost: about €60 (unit)
Maintenance cost of the barrier and weeding several times a year
Protective mesh/sleeve:
Voles: about €2/tree (about €2,000/ha for 1,000 trees)
"Social" criteria
Observation time: Increasing
Increasing
Autonomous trapping system but very important and very constraining weeding around the mesh (brushcutter, herbicide…), maintenance of the trapping area necessary and need to open the mesh at each intervention with a machine or to provide a door
4. Favored or disadvantaged organisms
Favored bioagressors
| Organism | Impact of the technique | Type | Details |
|---|
Disadvantaged bioagressors
| Organism | Impact of the technique | Type | Details |
|---|---|---|---|
| vole | pest, predator or parasite | ||
| beaver | pest, predator or parasite | ||
| cervids | pest, predator or parasite | ||
| European rabbit | pest, predator or parasite | ||
| hare | pest, predator or parasite |
Favored Auxiliaries
| Organism | Impact of the technique | Type | Details |
|---|---|---|---|
| Weasels, martens, ermines | Natural enemies of bioagressors | ||
| Foxes | Natural enemies of bioagressors |
Disadvantaged auxiliaries
| Organism | Impact of the technique | Type | Details |
|---|---|---|---|
| Frogs and toads | Natural enemies of bioagressors | If traps are too close to the meshes, frogs can be trapped |
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
- Alternative control methods against the Provence vole
- -Tronel C., Bouniol M.
CTIFL, Technical brochure, 2013
Infos-Ctifl, 295, 32-35
6. Keywords
Bioagressor control method: Physical control
Mode of action: Barrier
Type of strategy regarding pesticide use: Substitution
Annexes
S'applique aux cultures suivantes
Favorise les auxiliaires
Défavorise les bioagresseurs suivants
Défavorise les auxiliaires
