Skip to main content

Society for the Protection of New Hampshire Forests

Get our e-news! Sign up

small nav

  • About Us
    • Contact Us
    • Staff
    • Board of Trustees
    • Our History
    • Employment
    • Conservation Center
    • FAQs
    • Partners
    • Business Members
    • Annual Reports
    • Bylaws
    • Policies
  • log in
  • Facebook
  • Twitter
  • Instagram

Main menu

  • What we do
    • Land Conservation
    • Education & Events
    • Advocacy
    • Forestry & Recreation
    • News & Features
    • Forest Notes & More Publications
  • Current Projects
    • Mahoosuc Highlands, Shelburne
    • Forest Society North at The Rocks Campaign
    • Build Creek Farm Restrooms, Portsmouth
    • Mount Major Stewardship Fund
    • Recent Accomplishments
  • Visit & Explore
    • The Rocks
    • Conservation Center
    • Mount Major
    • Creek Farm
    • Forest Reservation Guide
    • Visitor Use Guidelines
  • Get Involved
    • Upcoming Events
    • Membership/Renewal
    • Support Our Work
    • Volunteer
    • Subscribe to E-news
  • Search

Search form

Donate
Menu

News

  • Something Wild Celebrates 25 Years on NHPR

    Dave Anderson, Chris Martin, Jessica Hunt
    March 10, 2023

    This week marks the 25th anniversary of Something Wild on NHPR.

  • Forestry Friday: Foresters Exchange Ideas at Annual Meeting

    Steven Junkin
    February 16, 2023

    The morning started with updates from Forest Society’s president Jack Savage.

  • An Endless Summer to Remember.

    Dave Anderson
    November 21, 2022

    It snowed last night: a three inch thick coffin lid to our seemingly endless summer. The first snowfall arrives like a shot across the bow. We’d ...

Forestry Friday: White pine weevil

Steven Junkin
March 24, 2022
Forestry
A white pine weevil adult on a branch.
An adult white pine weevil.

The latest Forest Health Update has just been released, check it out here.

This reminds me of one particular pest that makes its home in our woods and attacks trees in order to stay alive and complete its life cycle. This pest, which provides visual cues of its impact for decades, is the white pine weevil.

And, as it turns out, this pest is native to NH — however, it's no less destructive to tree health. It doesn’t kill the white pine trees but leaves them severely deformed and vulnerable to breakage.

A weeviled white pine at Heald Tract in summer.
These several pines were attacked by weevils.

A weeviled white pine at Ashuelot River Headwaters Forest.
This pine was attacked by weevils at a young age.

An adult white pine weevil lays its eggs on the terminal branch (the top leader). Then, the larvae hatch and feed their way into this branch, killing it. Side braches or “leaders” attempt to take the lead for that top branch spot.

This reaction is called apical dominance, a growth reaction that white pine trees portray strongly.

Because there can be as many as five leaders all shooting upwards, this causes a tree to form multiple large limbs all at one point on the tree.

A weevil-killed leader on a pine tree.
A weevil-killed leader.

 

A weevil-free tree will be perfectly straight with its top most branch always forming the top of the tree.

A non-weeviled pine trunk at Jennings Forest, New Durham.
A non-weeviled pine at Jennings Forest in New Durham.

Trees growing in the sun are most susceptible to this pest, whereas trees growing in partial shade tend to be less attractive. Forest managers can take this into account when the goal is to grow pine for optimum health and quality lumber by ensuring there is an appropriate level of shade in the first 10 to 15 years of its life. If a young pine does happen to get attacked, there is a pruning technique that exploits the trees nature of obtaining a dominant leader.

By pruning all but one of the 5 lower leaders, the tree will once again grow a nice, straight stem.

A pre-pruned weevil inflicted pine tree.
Before: A pre-pruned weevil inflicted pine tree.
The top leader has been removed on this pruned, weevil-inflicted pine tree.
After: the pine has been pruned.

Download the Forest Society Mobile App, powered by OuterSpatial

Available on the App Store
Get it on Google Play

Footer menu

  • Privacy Policy
  • About Us
Society for the Protection of New Hampshire Forests54 Portsmouth St.Concord, NH 03301
Phone: 603.224.9945Fax: 603.228.0423info@forestsociety.org
Land Trust Alliance accreditation logo