Have you noticed white rings on the trees in Milan?
If you live in municipalities in the provinces of Milan, Varese, Monza Brianza and Como, perhaps you have noticed strange white rings hanging from the branches of some trees. They look like ribbons, or slightly sinister decorations. But what are these formations really? Let’s see why we find white rings on plants.
White rings on plants: A new pest from Japan
After the arrival of the Popillia japonicafrom the Asian bedbugof theAnoplophora chinensis (and so on and so forth), here the East gives us another parasite: the Takahashia japonica.
Takahashia japonica is an insect of oriental origin belonging to the family of Coccidia. described for the first time in 1896 on mulberry trees (Morus spp.) in Japan and also widespread in China, South Korea and India. It turns out extremely polyphagousas it is capable of attacking many plant species.
A cochineal, yes. But with style. Like a Yuri Chechi of the insect world, this one loves rings.
What are those white rings on the trees?
White rings on plants: Which plants are affected by Japanese mealybug
The white ring formations seen on trees such as:
- Acer spp. (above all Acer pseudoplatano)
- Albizia julibrissin
- You are looking for a forest (Judas Tree)
- Carpinus betulus (Hornebe)
- Black mulberry And White mulberry (Mulberries)
- Elm spp. (Elms)
- Liquidambar styraciflua
…they are not artistic decorations but ovisacchi of one Japanese cochineal: THE Takahashia japonica.
Why specifically in Milan?
It is no coincidence that many cases are recorded near Malpensa. Planes, people, suitcases, hair. Maybe your hair, if you’ve recently been to Tokyo. Coincidences? 🌚
What is Takahashia japonica?
Identikit of the insect
Originally from Japanwhere it was described for the first time in 1896, this species has subsequently spread to other Asian countries such as China, South Korea and India. Its first appearance in Europe was recorded only in 2017, in Cerro Maggiore (MI), where it was identified on a specimen of Liquidambar styraciflua. Belonging to the Coccidae family, it is a polyphagous insectcapable of attacking numerous plant species. Currently its presence is documented in several provinces of Lombardy, including Milan, Varese, Monza Brianza and Como.
Ovisacchi: how to recognize them?
These waxy structures, which can reach even i 7cm longthey are particularly resistant to atmospheric agents such as rain, cold and bad weather. Inside they contain thousands of orange-colored eggs and attach themselves firmly to the branches of plants, particularly near pruning cuts, where they find favorable conditions for development.
Does Takahashia japonica harm plants?
At the moment, according to the Phytosanitary Servicethey are not here serious damage observed. However, in case of heavy infestations, drying of the branches may occur.
Good news: it is not dangerous for humans or animals.
Life cycle of Takahashia japonica
Only one generation per year
- Spring (April-May): adult females produce ovisacks
- Egg Schlusa: they come out neanidis (small scale insects)
- The nymphs migrate on leaveswhere they grow by sucking sap
- In the summer they become nymphs
- In fall they return to the branches and there they overwinter
- The cycle starts again in spring
How to fight Japanese mealybug
Physical interventions
- In case of localized infestations: phytosanitary pruning to remove infested branches
- No effect using insecticides directly on the sheep bags
Chemicals (with caution)
Currently there are no specific insecticides officially approved. However, the literature suggests:
- Acetamiprid (no longer on free sale)
- Alternatively: Flupyradifurone (e.g. Sanio)
Sustainable (and DIY) approaches
Recommended treatments
- Mineral oils: at vegetative growth or after hatching, they suffocate the juvenile forms Examples: mineral oils or even vegetable oils (soya, sunflower, flax)
- Neem oil + orange essential oil dosage: 10 ml of neem + 8 g of orange in 1 liter of water
- Potassium soft soap to add to the above mixture (10 ml)
- Microbiological preparations (e.g. Lecanicillium lecanii) In experimental phase
- Endotherapeutic treatments At the moment, little data is available
Predatory insects
- Adalia bipunctatawas observed in the presence of T. japonica
- The real impact on a large scale is not yet known
How does it spread?
Takahashia japonica spreads by traveling exploiting the wind: in the presence of monospecific trees or through passive transport: by means, tools, infested plants, pruning.
What is the Lombardy Region doing?
Conclusion: rings yes, but without Tolkien
THE Takahashia japonica it is still little known, difficult to control, but not dangerous for humans. We need vigilance, common sense and an integrated approach, if possible sustainable.
When in doubt, let’s avoid random insecticides and rely on targeted methods and territory monitoring.