NHBugs

Protecting trees and forests

Recommendations for homeowners and landowners

Management zones

Generally infested area
Emerald ash borer is in this zone, though not necessarily in all ash trees.

Potential expansion area
Emerald ash borer isn't known to be in the area, but the area is within 10 miles of the outer limits of the known infestation. There is a high probability emerald ash borer will spread naturally to this zone within a few years.

Alert area
Emerald ash borer isn't known to be in the area and it is more than 10 miles from the known infestation.

Quarantine
A quarantine of all hardwood firewood, ash wood-products and all ash nursery stock is in effect for Hillsborough, Merrimack, and Rockingham counties. To learn about the quarantine.

Definitions

Diameter at breast height (DBH)- Diameter of a tree at 4.5 feet above the ground

High-value ash- A tree valued for economic, ecological, aesthetic or cultural reasons.

Trap tree- A low-valued ash girdled to attract EAB and monitored by the N.H. Division of Forests & Lands.

Recommendations for All
  1. Management zones, based on current known infestations, are established for all of New Hampshire. Know your zone. Vew updated maps. (see map):
    • Generally infested area
    • Potential expansion area (within 10 miles of the infestation)
    • Alert area (beyond 10 miles of the infestation)
  2. Inventory your trees by species, size and value.
  3. Evaluate ash trees for signs of EAB. Report suspect trees or insects.
Generally infested
Landscape trees:
  1. You may remove all known infested trees near structures, cars and roads.
  2. Consider insecticide treatment for high-value ash. Ask three licensed pesticide applicators for quotes.
  3. Consider removing remaining ash trees while they’re still healthy—dying ash can be hazardous to remove.
  4. Use the material locally as the quarantine allows, to prevent movement of EAB.
Trees in natural settings:
  1. Ash may be harvested as small as 6-inches dbh. Leaving some ash standing slows the movement of EAB.
  2. Follow best management practices to limit accidental EAB spread. Consult the quarantine if moving ash material out of the current quarantine area or out of state.
Potential expansion area
Landscape trees:
  1. Consider removing ash trees while they’re still healthy—dying ash can be hazardous to remove. 
  2. Consider insecticide treatment for high-value ash. Ask three licensed pesticide applicators for quotes.
  3. Identify large, healthy ash trees and monitor them for signs of EAB regularly.
Trees in natural settings:
  1. Ash may be harvested as small as 6-inches dbh. Leaving some ash standing slows the movement of EAB.
  2. Identify large, healthy ash trees and monitor them for signs of EAB regularly.
  3. Follow best management practices to limit accidental EAB spread. Consult the quarantine if moving ash material out of the current quarantine area or out of state.
  4. You may create trap trees to help detect EAB early. Please contact 603-464-3016 for help.
Alert area
Landscape trees:
  1. Consider removing ash trees while they’re still healthy—dying ash can be hazardous to remove. 
  2. Identify large, healthy ash trees and monitor them for signs of EAB regularly.
Trees in natural settings:
  1. Ash may be harvested as small as 6-inches dbh. Leaving some ash standing slows the movement of EAB.
  2. Identify large, healthy ash trees and monitor them for signs of EAB regularly.
  3. Follow best management practices to limit accidental EAB spread. Consult the quarantine if moving ash material out of the current quarantine area or out of state.
  4. You may create trap trees to help detect EAB early. Please contact 603-464-3016 for help.