Deer exclosures

Flat Rock Brook Nature Center’s forest has experienced extensive habitat degradation caused by the overpopulation of deer feeding on native tree seedlings and saplings. Overgrazing deer prevent the forest from naturally regenerating. The shrub layer disappears, leaving a barren understory that is no longer able to function as habitat for wildlife. This problem, combined with the rapid spread of non-native and invasive plants, is compromising the overall health and biodiversity of the forest. This has become a serious threat to forests across the state of New Jersey. The primary objective of fencing is to keep deer out of sensitive areas in the park to prevent further damage to our native vegetation.

Our Board of Trustees and staff began discussing deer management options several years ago. After careful research and consultation with authorities that weighed various solutions, it was decided that deer exclosures would be the most effective resolution. Creating deer exclosures on the preserve offers the most sustainable and effective method for long-term forest health and regeneration. Protecting crucial habitat within the preserve will give the forest understory a chance to regenerate and rebound after years of extensive damage. Native plant communities will return, biodiversity will increase and viable wildlife habitat will become more readily available.

Construction of the deer exclosure was completed in September 2017. The fencing project resulted in two separate deer exclosures, a small area located at the Jones Road Picnic Area (approximately 20 acres) and a larger section surrounding a majority of the remaining forest (approximately 80 acres). An estimated 50 acres of the park will remain unfenced and accessible to deer, including the brook and wetland.

This project is an essential first step in protecting the health, biodiversity and wildlife of the forest. The exclosures are management tools, and require maintenance and monitoring to be effective.The success of this project depends on hikers and community members responsibly closing access gates within the preserve. The gates will be located in areas where the fence line intersects with a trail. Please be sure to close these gates behind you after walking through these entrances. The installation of a cattle grate at the park’s main entrance gate will allow it to remain open during normal park hours without re-entry of deer into the park. This keeps the main parking area and driveway open during visiting hours so that access to the preserve will remain undisturbed. Thanks so much for your cooperation on this important project that will benefit the health of the forest.

Habitat Restoration

There are some areas of the forest that have become so severely degraded that they are not likely to regenerate naturally. A complete disappearance of standing trees, communities of native vegetation, and useful wildlife habitat has occurred.  We are targeting these areas as restoration projects.  A team of botanists and specialists assessed and surveyed the two restoration areas and crafted two site-specific design plans characterized by select native plant species. 

Pollinator Meadow Restoration Project:  Flat Rock Brook has a 0.2 acre meadow that has been severely impaired over time.  Deer browsing and the proliferation of invasive species such as mile-a-minute vine and japanese stilt grass have compromised its value to wildlife species and pollinating insects and birds. Meadows are a crucial component of a healthy forest by providing a food source throughout the food web. A restoration plan was created and implemented including a list of plant species for the meadow and a continued maintenance plan. In 2018, hundreds of pollinator specific native plants were added to the meadow while every fall native seeds are added to the seed bank.

Woodland Restoration Project:  Located inside the Summit Street entrance, is a 1.5 acre land parcel that has been badly damaged by deer grazing and is dominated by invasive plant species like wineberry and garlic mustard. A woodland restoration plan was created to increase woody vegetation while treating for invasive species. Flat Rock has begun working on this project by clearing the overgrown brush and monitoring regrowth of invasive plants. Once the invasives have decreased to a manageable level, the site will be slowly replanted in an effort to increase the longevity of new plantings.

Invasive Species Management: The takeover of invasive plant species has become evident in the forest at Flat Rock Brook.  Invasive species quickly spread through a forest ecosystem damaging it in a number of ways. First, they out compete native vegetation for resources and prevent native communities from growing back. Second, new woody plant growth is smothered preventing forest regeneration. Third, they decrease the levels of overall biodiversity within the forest ecosystem by creating monocultures that provide little to no benefit to wildlife. This is detrimental for forest health and for the survival of numerous wildlife species. When the forest loses its diversity, the habitats available for wildlife will eventually decrease or disappear.

Flat Rock Brook uses Integrated Pest Management (IPM) to properly treat invasive species. Every species of invasive plant is carefully researched to provide careful consideration of all available pest control techniques. Some examples of IPM include the release of mile-a-minute weevils that eat only the vine, and pulling garlic mustard before it creates hundreds of seeds. By integration of appropriate measures that discourage the development of invasive species, pesticides and other interventions  can be kept to levels that reduce or minimize risks to human health and the environment. 

In 2018, a comprehensive survey of the flora on the preserve was completed to provide information for treating invasive species. This survey provides spatial  and numerical data of several invasive species and the size of local colonies that could potentially spread to other areas of the park.   This is crucial for efficiently treating invasive species by treating high risk areas first.  A follow up survey will be completed every few years to continue providing data for land management strategies, and map the spread of both native and non native flora. 

Using this information, Flat Rock Brook can better implement its 10-year forest stewardship plan that focuses specifically on the targeted eradication, effective management and consistent monitoring of invasive plant species.

Vegetation Survey and Monitoring Project

Through the generosity of private donations, Flat Rock Brook conducted a survey to monitor the current vegetation across the  150-acre preserve and see how they change in their structure, composition, stability and overall health.  This study is one of the most important steps to measure how the forest is responding to the management strategies being implemented.  It also identifies areas of high priority in the forest that need more focus and resources.  The primary goal is to facilitate regeneration of native plant communities and allow the forest understory to recover and return.

The vegetation study and monitoring project has three important outcomes:

• Provide a baseline data set of plant species in our forest, including characteristics and location

• Monitor the health of the forest by using a Floristic Quality Assessment (FQA) to establish high risk areas and areas of high ecological value.

• Creating public, student  and professional opportunities to engage in land management at Flat Rock Brook

Water Quality Monitoring Program

Much of the water flowing through Flat Rock Brook comes from runoff of rainfall and snowmelt throughout the surrounding suburban developments. Flat Rock Brook  is monitoring the following water characteristics to help people understand the impact they can have on aquatic ecosystems, to identify specific problems, and to work towards solutions of those problems. Water samples are taken regularly from several locations along Flat Rock Brook, including both the northern and southern tributaries upstream from McFaddens Wetland, and in the stream at the picnic area along Jones Road. 

Wildlife Survey

In 2019, Flat Rock Brook conducted a comprehensive wildlife survey and assessment. The study covered the entire 150-acre property and focused on surveying for birds, deer, amphibians, reptiles and lepidoptera (butterflies and moths). These fauna were picked due to their correlation to habitat degradation, and how their abundance or absence can affect future land management. The survey provides crucial information about the presence, abundance, distribution, location and patterns of these wildlife species that call Flat Rock Brook home.This wildlife survey has four important outcomes:• Provides a baseline data set describing the wildlife species currently present at Flat Rock Brook.• Acts as a parameter for measuring the impacts of the deer exclosures.• Identifies and assigns “bio-indicator” species, or species that are representative of overall forest and ecosystem health at Flat Rock Brook.•  Identifies if any endangered species, threatened species, or species of conservation concern exist at Flat Rock Brook.