Taste repellent (fish meal and phosphoric acid)

This group of agents belongs to repellent substances. Their mechanism is based on creating a persistent unpleasant odor and a specific gustatory barrier that alerts animals of danger or unpalatability.

Fish meal serves as the primary source of a strong protein-based odor, mimicking decomposition products, which triggers an instinctive avoidance reaction in wild animals.

Phosphoric acid in the mixture acts as a stabilizer and an active irritant. It stabilizes the organic component and causes temporary irritation to mucous membranes if the animal attempts to taste the treated plant.

The combination of these components provides a dual effect: distance (through smell) and contact (through taste buds), forcing pests to abandon the treated area.

These products are biodegradable and environmentally safe, as they do not accumulate in plant tissues and act solely as a deterrent to restrict access.

The primary targets for these applications are wild ungulates: roe deer, deer, moose, and wild boars, which cause significant damage to young forest plantations and grain crops.

The preparations effectively protect fruit tree seedlings from bark gnawing during winter and early spring when natural food sources are scarce.

Repellents are used on corn and sunflower fields to prevent browsing during the seedling stage when plants are most vulnerable to wildlife damage.

The group is effective against hares and other small rodents that cause mechanical damage to trunks and stems of agricultural crops.

Using these compounds helps avoid crop losses caused by wildlife visits without the need for lethal control methods.

The application rate depends on the population density of the animals in the region and the level of attractiveness of the crop to the pests.

Products are most often applied by spot spraying the perimeter of the field or direct application to tree trunks and the vegetative mass of plants.

The timing of treatment is linked to animal migration periods or the phases of maximum crop vulnerability, such as the emergence of first sprouts.

Repeated treatment is recommended after heavy rainfall, as moisture can reduce the concentration of active components on the plant surface.

• Preventive treatment of the plot perimeter.
• Localized application on vulnerable plant parts.
• Reapplication every 14–21 days depending on weather conditions.

Despite high effectiveness, products containing fish meal may attract predators due to the specific odor, which should be considered when planning treatments.

When working with phosphoric acid, safety measures must be followed, as the concentrated composition can cause irritation to the skin and mucous membranes of the operator.

A limitation is the high dependency of effectiveness on rainfall: the product is washed off by water, necessitating regular renewal of the protective layer.

It is not recommended to use repellents immediately before harvesting to prevent the specific smell of the components from tainting the final product.

Before large-scale application, it is advisable to conduct a phytotoxicity test on small areas to rule out the risk of damaging the leaves of sensitive crops.