Comprehensive solutions for controlling vole pests in crops

Introduction to vole pest control in crops

El vole pest control in crops represents one of the greatest challenges for farmers and rural managers due to the reproductive and adaptive capacity of these small rodents. voles, particularly the peasant vole (Microtus arvalis), can cause serious damage to crops, garden areas and even infrastructure, which translates into important economic lossesIn addition to property damage, voles can transmit diseases such as tularemia, increasing the need for effective, sustainable, and responsible control.

The effectiveness of any control strategy depends on adequate knowledge of the biology, behavior y reproductive cycle of voles, in addition to the integration of different management methods that are respectful of the environment and biodiversity.

Why do voles become a pest?

El peasant vole stands out for its great reproductive capacity throughout the year, although it is in the spring season when they are most active. This allows them to go from a small population to a real pest in a short period of time, reaching densities greater than 1500 individuals per hectare under favorable conditions.

Being a species herbivorous, its diet includes stems, leaves, roots, tubers and bulbs, literally destroying whole crops, especially irrigated land and those with dense vegetation cover. They prefer soils damp but not waterlogged, where they easily excavate their galleries and burrows.

The proliferation of voles, in addition to being influenced by food availability and soil structure, is favored by:

• Simplification of the agricultural landscape (absence of vertical elements such as trees or bushes).
• Reduction of their natural predators due to the indiscriminate use of pesticides or habitat alteration.
• Agricultural practices such as direct sowing and the use of perennial forage crops, especially alfalfa.

The presence of holes in the ground, mounds of earth and traces of excrement are obvious signs of an active infestation that requires immediate intervention to prevent further damage.

Identification and damage caused by voles

The voles They are small, robust rodents with short tails and barely protruding ears. Their fur is generally yellowish-brown, with a lighter underbelly, and they lack obvious sexual dimorphism. The presence of superficial galleries and damage to roots, stems and leaves It is characteristic, affecting both herbaceous crops and young plantations of fruit or timber trees.

The most common damage caused by voles includes:

• Destruction of roots and tubers, leading to drying and death of the plants.
• Consumption of aerial parts (stems and leaves), which interferes with crop development.
• Ground instability due to the formation of galleries, affecting agricultural machinery.
• Disease transmission such as tularemia, which is relevant to both animal and human health.

Factors that favor the appearance of the plague

The increase in the vole population is directly associated with certain environmental and anthropogenic factors:

• Abundant rains, which facilitate the excavation of galleries and increase the availability of food.
• Absence of natural predators due to the simplification of the agricultural landscape and the use of poisons.
• Agricultural practices such as direct seeding or the maintenance of dense vegetation cover in tree crops.
• Abandonment or lack of cleaning of ditches, streams and boundaries, offering shelter and food.

The combination of these factors can trigger population explosions of voles that are difficult to manage with conventional methods. Hence the importance of prevention and continued surveillance as part of the control strategy.

Prevention and cultural measures for vole control

La prevention It is essential to limit the emergence and impact of vole infestations. Among the most effective cultural measures are:

1. Monitoring continuous monitoring of plots and surrounding areas, notifying the competent authorities of any signs of activity.
2. Cleaning of ditches, boundaries and streams by mechanical means (blade, brush cutter, motor grader) with the aim of removing herbaceous vegetation cover without damaging trees or valuable plant elements.
3. Maintenance of bare strips (between 5 and 10 meters) on the margins of cultivated plots at risk of pests, even considering leaving these strips unplanted if the threat is high.
4. Deep soil removal to destroy potential colonies, especially in direct seeding areas by using tillers.
5. Intensive and controlled grazing in stubble and wasteland to reduce the vegetation cover that could harbor voles.
6. Removal of stone accumulations, crop residues and pruning that can serve as a refuge.
7. Avoid accumulations of stagnant water, since voles prefer moist but well-drained soils.
8. Avoid maintaining unnecessary irrigation pipes in irrigated plots, especially in alfalfa crops.

Implementing these practices in a systematic and coordinated manner significantly reduces the voles' ability to establish successful colonies and limits their access to food and shelter.

Biological control methods: enhancing natural enemies

El biologic control Vole control is a sustainable and efficient alternative, especially in large agricultural areas where chemical treatments are costly and dangerous. Encouraging the presence of natural predators It constitutes one of the best tools for reducing vole population explosions, integrating natural regulation into agrosystems.

Among the main natural enemies that effectively control the vole population are:

• nocturnal raptors such as barn owls and common kestrels, capable of consuming hundreds of voles during the breeding season.
• diurnal raptors such as the red kite and the common buzzard.
• Carnivores such as weasels, foxes and badgers, as well as some species of snakes and storks.

Installation nest boxes or artificial nesting boxes on elevated posts, has shown remarkable results in reducing voles. This simple system facilitates the settlement and reproduction of predatory birds, increasing their numbers in critical pest-affected areas. Another interesting option is the use of repellent plants which can help keep these rodents away from small surfaces.

El biologic control presents additional advantages:

• Long-term cost reduction, since it does not require repeated applications.
• It does not generate resistance in the pest.
• It does not negatively impact biodiversity surrounding environment nor does it affect human health, as it does not introduce poisons into the ecosystem.

A pair of kestrels, for example, can consume around 700 voles during the breeding season, becoming a valuable natural ally for farmers.

Ecological management and sustainable practices for pest reduction

La sustainable agricultural practice It is essential to prevent the proliferation of voles. Some additional recommendations:

• Promote landscape diversity and the presence of hedges, small forests and semi-natural elements that allow for the refuge and reproduction of natural predators.
• Eradicate the indiscriminate use of pesticides that may negatively affect the voles' natural enemies.
• Promote minimum tillage at specific times and in specific areas, especially where burrows are observed, to disrupt established colonies.
• Encourage crop rotation and avoid the continued implementation of multi-year crops that are highly favorable to voles, such as alfalfa.

Physical and mechanical methods for vole control

In addition to prevention and biological control, there are physical and mechanical methods that can be integrated into pest management:

• Metal traps to capture voles live, subsequently releasing them in less sensitive areas (especially effective in small areas such as orchards and gardens).
• Instant bait traps, intended for the extermination of the rodent at the point of capture.
• Placing containers with water near burrows or passageways (voles fall in and cannot escape, making this method useful only in small, localized areas).
• Ultrasound: Deterrent devices that manage to keep away a significant percentage of the pest, although they are not effective in large areas or for individuals native to the area.

These methods should be used in combination, always assessing their suitability based on the magnitude of the pest, the affected area, and the immediate surroundings, taking care to avoid unnecessary damage to beneficial fauna.

Use of repellent plants and natural control

The repellent plants They are a natural alternative to scare away voles in small areas, such as gardens or urban allotments. Species such as the thorn apple, belladonna, castor oil y Brown, all of which contain roots rich in atropine, have demonstrated some deterrent effect, although their effectiveness decreases when vole concentrations are high. Jimson weed, in particular, is known as a repellent for moles and mice and can be part of an integrated control strategy.

Chemical Control: Risks, Regulations, and Best Practices

El chemical control with rodenticides should be considered only as a last resort due to the serious secondary effects on the environment and wildlifeThe indiscriminate use of anticoagulants or poisoned baits can affect other species of birds, mammals, and reptiles, and even human health in the case of indirect exposure.

It is essential to take into account:

• The application must be selective and controlled, strictly following the labeling instructions and current regulations.
• Only authorized personnel or those under the supervision of the competent authorities should handle these products.
• Regular monitoring is essential to avoid secondary poisoning.
• In some areas, aerial or surface treatment with rodenticides is prohibited, prioritizing integrated management techniques.

Massive rodenticide campaigns have demonstrated limited effectiveness and have had adverse effects, such as the emergence of resistant voles, mortality of birds of prey, and the transmission of diseases such as tularemia through the handling of infected carcasses. Therefore, Chemical control should only be used in exceptional situations and after exhausting all other alternatives.

Adaptive monitoring and management

a correct one monitoring It allows for early detection of pests, facilitating early action and the application of targeted measures. The main monitoring tools include:

• Periodic inspection of holes and galleries in plots and roadsides.
• Observation of signs of crop damage, such as loss of vigor, dry plants, gnawed roots or broken stems.
• using witness traps and capture monitoring to estimate the density of voles in the area of ​​interest.

La adaptive management It consists of adjusting control measures based on monitoring, the evolution of the pest and the results obtained, promoting maximum effectiveness and minimum environmental impact.

The importance of coordination between farmers and administration

La coordination between farmers, technicians and administration is key to the success of integrated vole control programs. Early notification, participation in surveillance campaigns, and the implementation of technical recommendations ensure an effective response and minimize the risk of economic and environmental losses.

Furthermore, raising awareness about the importance of respecting auxiliary fauna and natural enemies strengthens the agrosystem's resilience to future vole population explosions.

Based on the accumulated experience and studies carried out in different regions, some complementary actions can be implemented:

• Temporary flooding from infested plots, provided that the structure and type of crop allow it, to force the exit or death of the voles.
• Manual destruction from burrows using tools such as a hoe or with specific machinery (surface grade) to break galleries.
• Delayed planting in the areas of greatest activity, adjusting the periods to the low density of voles.
• Removal of irrigation pipes off-season on irrigated plots, to prevent them from becoming a refuge.

Tackling the vole infestation requires combining prevention, monitoring, physical, biological and cultural managementChemical control should be reserved as a last resort, always ensuring the protection of biodiversity and public health. The integration of all these methods, along with the collaboration of farmers, technicians, and administrations, leads to more sustainable production systems that are resilient to future pests.