Emerald Ash Borer - Imidacloprid

Imidacloprid

Imidicloprid (trade names Merit, Xytect, Optrol, ArmorTech, Enforce, Hawk-I, Turfthor, Malice, Premis, Criterion, Hunter, Submerge, Tuchstone, ZENITH, Bandit...) is applied to the soil within 1 foot of the tree trunk at a depth of 3 - 4 inches. It is most commonly applied using a soil injector that injects it evenly around the trunk. It can also be applied as a drench or in a small moat around the tree trunk. In university research, Imidacloprid treated trees only survived the most severe level of infestation when treated at the 2X rate. The trees treated with the standard Imidacloprid rate died. This research led to the EPA amending the Rainbow Treecare Xytect imidacloprid label to allow this higher rate for treating the emerald ash borer. This product is typically applied by a professional Arborist. However, Imidacloprid is not restricted and homeowners can protect their own trees without a needing a license. Bayer Advanced Tree and Shrub II has 1.47%-2.94% active Imidacloprid, which shows most effectiveness on small trees 8 inches in diameter (DBH) or less. 22%, 44% and 75% active ingredient of Imidacloprid is available for treating trees larger than 8 inches in (DBH) diameter.

Whether higher or lower percentage product used, all achieve same end dose. Higher percentage insecticide just calls for less powder amount. Imidacloprid "Falls" out of water quicker, the higher the percentage of active ingredient is used. Tree-injection methods use the 5%-10% active ingredient amount of Imidacloprid. Special proprietary Injectable formulations of Imidacloprid are refined to facilitate uptake of product through trees small diameter drinking straws called the xylem.

The Positive Aspects of Imidacloprid Are

• Lowest cost treatment. Cities and neighborhood can treat an average tree for between $15– $20.
• Tree is not wounded by the treatment application method.
• Proven to provide an excellent level of defense when used at the 2X rate.
• Homeowners can apply to their own trees.

Downsides of Imidacloprid

• Treatment is annual. (Required for effectiveness)
• Should not be applied to trees within 10 feet of creeks, ponds, or lakes. It can harm water insects and insect larvae if applied directly to water.
• After application it takes 30 to 60 days for imidacloprid to move up into the tree with enough strength to become effective.

Costs of Imidacloprid

• Large city bids for thousands of trees are ranging from $1.05 to $1.25 per diameter inch (DBH) for a professional application.
• Smaller communities with fewer trees can expect to pay more.
• Communities can save about 20% by treating their own trees.
• Homeowners costs are higher, and range from $4.00 - $8.00 per diameter inch (DBH) for a single tree treated by a professional.
• Do it yourself homeowners can treat their own tree 20 inch diameter (DBH) for $38 – $50.