An insecticide is mixed with water and injected into the ground around the tree, the tree takes up the chemical through the roots and delivers it to the leaves where the Elm beetles and larvae ingest it. One treatment usually lasts for 3 years. We have a 2 year guarantee.
Many of our clients successfully run a 4 or 5 year cycle with soil injection, this can depend on the movement of beetles in the area and takeup factors. If your tree is not bieng significnatly impacted we suggest you delay treatment.
Our preferred chemical application method is stem injection due to the significant environmental issues associated with this chemical type, see ‘Disadvantages’ below.
Advantages of soil injection
- No over-spray as with foliage sprays
- soil injection for Elm Beetle is long lasting: usually 3 years
- The level of beetle control is very good given the right conditions
- There is no damage to the tree structure or garden as with a stem injection treatment which creates permanant wounds and the spread of decay in the trunk
- Economical compared with annual treatments such as spraying
- Makes additional water available to the tree
- 2 year guarantee on treatment – if the treatment is not working adequately we re-inspect and do a follow up treatment at no extra cost
Disadvantages of soil injection
- Introduces more chemical to the environment and more broadly.
- Importantly this method makes the chemical available to all plants in the area, not just the Elm, and therefore exposes many pollinators including bees to the chemical
- Elm Leaf Beetle Treatment via the soil has a lag time of some weeks (5 approx), therefore treatment is carried out prior to the tree coming into leaf or a foliar spray can be done at the same time (when tree is in leaf) to cover any time lapse
- Root zones of some target trees are not accessible, they may be under driveways or paved areas
- Organisms in the soil, such as worms, in the immediate area of soil injection may be harmed or killed
- Cannot be used adjacent to water bodies due to toxicity
- In dry conditions the soil may require additional water however this added water is good for the general health of the Elm tree