Forest Management at Ludlow Reservoir

In 2016, a spongy (formerly known as "gypsy") moth infestation was discovered in the Ludlow Reservoir watershed forest, resulting in irreversible and eventually fatal damage to a large number of oak trees. In response, the Commission developed a comprehensive plan for forest management activities which were implemented in 2018 until 2020. Forest management activities included tree harvesting within the Ludlow Reservoir watershed forest.

Common Questions

What is forest management?

Forests are managed for a variety of reasons. The Commission actively manages watershed forest lands for the purpose of source water protection and has adopted forest management practices that promote water quality protection.

The Commission works with licensed consulting foresters that are experts in the field. All forest management plans are required to be approved by regulatory agencies, such as the Massachusetts Division of Fish and Wildlife and the Department of Conservation and Recreation.

What is a watershed forest?

The Ludlow Reservoir was built in the 1870s, and now serves as an emergency backup water supply for the Commission’s public water system. The primary purpose of the 1,400 acres of forest surrounding the reservoir is to protect water quality by acting as a natural buffer from surrounding development, and as a natural filter of potential contaminants.

A forest that is diverse in age and species provides the best water quality protection. A good watershed forest is biologically diverse (i.e. numerous species), structurally diverse (i.e. wide range of tree ages), and able to naturally regenerate itself. These qualities make a forest more resilient to stressors such as disease and invasive pests, thus supporting water quality protection.

What are spongy moth infestations?

Spongy moths are an invasive species that was accidentally introduced into the environment in Medford, Massachusetts, in 1869. Since then they have been a reoccurring and spreading problem in northeast hardwood forests. Spongy moths feed on the foliage of mature trees, stripping the trees’ ability to photosynthesize and generate the energy needed to heal and grow. Successive defoliations may kill trees outright or leave them susceptible to secondary pests and pathogens.

The last spongy moth infestation at Ludlow Reservoir was in the 1980s. Spongy moths prefer oak trees, a significant part of the forest cover in the Ludlow Reservoir watershed. In 2018 the Commission’s consulting forester documented that trees affected by successive spongy moth infestations did not regenerate with a second set of leaves, and reported that mortality of a large number of oak trees was imminent. (Read the foresters report to the Commission).

What are the goals of tree harvesting in response to spongy moths?

There is no known method to reverse spongy moth damage. Tree harvesting serves the following goals:

• To promote greater species diversity including trees and shrubs that need to grow in full sun
• To remove trees that pose a public safety hazard
• To capture timber value contained within trees fatally affected

How was the tree harvesting managed?

A licensed forester conducted an evaluation of each stand of trees identified as suitable for harvesting and marked each tree to be removed or retained. The goal of this careful selection is to beneficially shape future forest conditions to protect water quality. In some cases, other issues may also be addressed, such as thinning of over-crowded white pine trees.

The Ludlow Reservoir watershed land is also protected by a conservation restriction held by the Massachusetts Division of Fish and Wildlife, which requires an approved forest management plan. The plan was approved on November 6, 2018. Cutting plans for the tree harvest are guided by the Ludlow Reservoir forest management plan, and were approved by the Department of Conservation and Recreation on November 20, 2018. The forest cutting plans were also reviewed by the Ludlow Conservation Commission and the Natural Heritage and Endangered Species Program (NHESP). A Massachusetts Licensed Forester supervised harvesting activities on behalf of the Commission.

Why not just let nature just take its course?

In many areas, it will.  Trees will die and decompose in place in areas that are not suitable for tree harvesting such as in wet areas or where the land is too steep. The look and composition of the forest in those areas may change significantly from what it is today. In the other areas, harvesting will be utilized as a strategy to promote the full spectrum of tree and shrub diversity including trees and shrubs that need to grow in full sun.

How did this impact public recreation at Ludlow Reservoir?

The landscape and tree canopy at Ludlow Reservoir changed significantly after tree harvesting, and may still be noticeable to visitors in areas. Taller oak trees were removed resulting in much more sunlight on the recreational path. The terrain also looks more disturbed and more dead trees will be visible as the forest cycle progresses. The impacts of harvesting will become less visible over time as the forest continues to grow.