Answering the question of how to protect ash trees from the Emerald Ash Borer, this guide highlights effective systemic treatments and implants designed to defend trees for up to a year or longer. The top picks below are best for homeowners seeking long-term protection, professional-looking results, and easy, low-maintenance application. The buyers here range from those treating a single tree to those managing multiple landscape specimens.
Summary of selected products:
- Fertilome Tree & Shrub Drench Systemic Insecticide (1 gal) — Imidacloprid, up to 12 months protection.
- Acecap 25-Pack Systemic Tree Implants — Season-long control, up to two seasons in evergreens.
- BioAdvanced 12 Month Tree & Shrub Protect & Feed Concentrate (32 oz) — Kills Emerald Ash Borer and provides year-long protection plus plant nutrition.
- Medicap Acecap AC12X5 Systemic Insecticide Tree Implant — 5-pack for season-long control in ornamentals.
- Acecap AC4X75 Tree Implant — Brown implant, season-long control for trunk-diameter protection.
Fertilome Tree & Shrub Drench: Imidacloprid Systemic
Best for homeowners with a single or a small number of trees seeking long-lasting protection. The systemic formula provides up to 12 months of protection against a broad range of insects, including aphids and beetles. The product is designed for outdoor residential use on trees and shrubs, delivering root uptake for lasting defense.
Best for: Homeowners with a few trees and shrubs needing year-long protection without frequent reapplication.
Caution: Ensure proper dilution and application according to the label to avoid over- or under-application. Suitable for outdoor use only.
Acecap 25-Pack Tree Implants
Best for larger trees or multiple specimens where implants offer a controlled, target-delivery method. These implants provide season-long control and can extend to two seasons in evergreen trees. Ten implants typically treat up to a 14-inch trunk diameter, reducing repeated applications.
Best for: Landscapes with several susceptible trees or where a slow-release method is preferred over liquids.
Caution: Implants require proper placement and maintenance; improper insertion can limit effectiveness. Avoid if you have evergreen trees smaller than the diameter threshold.
BioAdvanced 12 Month Protect & Feed Concentrate
Best for trees requiring both pest protection and feeding. This concentrate delivers a 12-month shield against pests like Japanese beetles, emerald ash borers, and aphids while providing slow-release plant nutrition to improve overall tree health. Suitable for large trees and container plants alike.
Best for: Those who want combined protection and fertilization in one product to maintain tree vigor.
Caution: Follow mixing ratios precisely to ensure effective pest control and plant nutrition; avoid over-fertilizing young or stressed trees.
Medicap Acecap AC12X5 Tree Implants
Best for ornamentals and larger landscapes needing robust, season-long pest control. This 5-pack provides easy spring application and dissolves in the sap to distribute the chemical systemically within the tree within 4–5 days. Ten implants adequately cover up to a 14-inch trunk diameter.
Best for: You manage multiple ornamentals or want a compact, long-lasting implant solution for a defined trunk size.
Caution: Ensure proper spring timing for optimal distribution; implants should be placed as directed to avoid ineffective coverage.
Acecap AC4X75 Tree Implant
Best for medium-sized landscapes where a brown implant is preferred and season-long protection is required. Ten implants are designed to treat up to a 14-inch trunk diameter, offering a straightforward, low-maintenance solution for sustained pest control.
Best for: Medium-diameter trees in mixed landscapes that benefit from a discrete, long-lasting implant approach.
Caution: As with other implants, follow exact placement guidelines for maximum effectiveness and monitor trunk diameter growth over time.
Buying Guide: Emerald Ash Borer Treatment Essentials
- Application method: Liquid drenches vs. tree implants each have pros and cons. Drenches are easy for single trees, while implants reduce field application time for multiple trees.
- Protection duration: Look for products offering up to 12 months of protection. Some implants provide season-long to multi-season coverage depending on tree type.
- Tree type and size: Match product to trunk diameter and tree species. Implants commonly specify coverage up to a 14-inch trunk.
- Health and nutrition: Some products combine pest control with fertilization, helping overall vigor and resilience against infestations.
- Environmental impact and safety: Choose products designed to minimize chemical exposure to applicators and non-target organisms. Follow label directions closely.
- Number of trees: For larger landscapes, consider multi-pack deals or implants to reduce labor and ensure even coverage across specimens.
Frequently Asked Questions
- What is the best overall treatment for Emerald Ash Borer? A systemic product with year-long protection is typically effective for a single-tree approach; for larger landscapes, implants may reduce maintenance time.
- How long does protection last? Many products offer up to 12 months of protection after a single application, depending on the product and tree type.
- Can I treat multiple trees with one product? Yes, particularly with tree implants or multiple bottles of systemic drenches designed for outdoor residential use.
- Are tree implants safe for evergreen trees? Some implants claim extended coverage in evergreen trees; verify labeling to ensure compatibility with evergreen species.
- Should I fertilize while treating? Some products include slow-release plant food; if not, consider pairing with a balanced fertilizer separately to promote tree health.
- When is the best time to apply? Spring timing aligns with sap flow for systemic distribution; always follow label-specific guidance for timing and placement.