Takahashia Japonica, a parasite of Japanese origin belonging to the cochineal family, continues to represent a growing threat to the trees in different Lombard provinces. Also known as “Cocciniglia with cotton filaments”, this insect appeared for the first time in Europe in 2017 in Cerro Maggiore, in the province of Milan. Since then, it has spread progressively in other Lombard areas, including the provinces of Milan, Varese, Como, Monza and Brianza.
The problem worsened
The latest reports of 2025 show a significant worsening of the situation. The first reports of the new infestation wave date back to Monza a few days ago, in particular in the Triante district and along Viale Elvezia, where the ring -shaped bags containing thousands of eggs have been noticed on various trees, including maples, white carpini, mulberry and liquidambar.
The problem seems to grow every year, with increasingly numerous reports of infestations in different areas. In Vimercate, the residents noticed a worsening of the situation compared to previous years. Also in the areas of Saronno and Uboldo, the Eco ’90 association received numerous requests for information regarding the white rings on the trees, confirming that it is Takahashia Japonica.
Features and damage
This mealybug feeds on the lymph of plants, initially causing yellowing and loss of the leaves, up to the drying of the younger branches and, in the most serious cases, of the entire plant. Takahashia Japonica is easily recognizable for its cotton -looking white ovizas, which remind the sight of the cotton rings and can also reach 7 cm in length. These ovisacchi contain thousands of orange eggs and are extremely resistant to weather and insecticides thanks to their cerful protective coverage.
How to stop this invasion
To counteract the invasion of Takahashia Japonica, the most effective method remains the physical removal of the infested branches, but this operation must be performed with extreme caution to avoid the spread of the parasite. It is essential to prune the branches before hatching eggs, which generally takes place between the end of May and the first weeks of June, paying particular attention to the disposal of the infested branches and the disinfection of the tools used.
Treatments currently in use
The Lombardy Region, through its phytosanitary service, confirmed that insecticides on ovisacchi interventions are not effective due to the cerful protective shield. Recommended treatments include:
Experimental biological struggle
In some locations, such as Vimercate, integrated struggle methods are being experienced using antagonist insects such as the bipunctated adalia ladybird, which can help reduce cochineal populations. However, this approach is assessed with caution for possible repercussions on local biodiversity.
Interventions of local authorities
In Bovisio Masciago, the local authorities have already started phytosanitary treatments on some trees to combat infestation. Although natural products are used, the residents have been warned to keep the windows closed and cover the crops during the precautionary treatments.
Monitoring and reports
The Lombardy Region has started systematic monitoring of reports to create a useful database for large -scale future interventions. It is important that citizens continue to report the presence of Takahashia Japonica using the phytodetective app or by contacting the regional phytosanitary service directly.
Although Takahashia Japonica is not dangerous for humans or animals, its growing diffusion in northern Italy requires a coordinated approach that combines preventive interventions, targeted treatments and constant monitoring. The key to success lies in intervening promptly before the infestations reach critical levels, when the removal of the entire plant can become the only available option.
