Viburnum opulus worms
My viburnum opulus is being destroyed by small greenish coloured worms. They are definitely not a beetle. How can I eradicate them and save my tree? Thanks.
Certified GKH Gardening Expert
They can be treated with products containing Bacillus thuringiensis (Bt), a natural bacteria that kill worms without harming plants. Neem oil may be helpful as well. Here is more information: https://www.gardeningknowhow.com/plant-problems/pests/pesticides/using-bacillus-thuringiensis.htm