forest management


An Introduction to the Plant Stewardship Index for Land Managers

January 23rd, 2013. 10:00 am – 12:00 pm. FREE

In case of severe winter weather, snowdate is January 30th, same time.

The Plant Stewardship Index is a crucial tool designed for land managers to monitor, assess, and communicate the health of wild plant communities and the success of stewardship and restoration initiatives.

In this free class, we’ll introduce the basics behind the Plant Stewardship Index and discuss its use in comparing the natural values of different sites and for assessing change over time.

Topics will include use of the free online PSI Calculator, using PSI metrics to communicate the integrity of wild plant communities, plant survey basics, and designing more advanced surveys using transects and quadrats.

The class will be given by Jared Rosenbaum, Plant Stewardship Index Coordinator at Bowman’s Hill Wildflower Preserve.

Location: The Classroom at the Duke Farms Orientation Center, 1112 Duke Parkway West in Hillsborough, N.J.

To Register: Call Bowman’s Hill Wildflower Preserve at (215) 862-2924 or e-mail by January 21st, 2013.


Jonathan Woods, Denville, NJ after Superstorm Sandy.

Superstorm Sandy changed many forests throughout New Jersey.  The way these forests recover can provide insight into how forests regrow given the unique conservation threats we face; how will overabundant white-tailed deer, non-native invasive species, air pollution deposition, and climate change affect forest regeneration?  Answering these questions will be critical if we are to move forward in a thoughtful and scientific way with active management of our natural resources.

Blowdown from Superstorm Sandy at India Brook Park, Mendham, NJ

Blowdown from Superstorm Sandy at India Brook Park, Mendham, NJ

The focus of the next Stewardship Roundtable meeting will be to discuss these issues and determine what we may be able to do to monitor forest recovery after Sandy.  Given this unprecedented opportunity, what questions can we begin to answer? With limited stewardship resources, can we develop a monitoring program that answers our questions and is low cost and consistent across sites?

The meeting will be on Monday, January 14 2013 from 10AM to 12:30AM at NJ Audubon’s Scherman-Hoffman Wildlife Sanctuary.  We will first meet indoors to broadly discuss this topic and then we will visit a nearby blowdown.

Emile DeVito asked that we post this to the stewardship roundtable.  A pdf version of the signed letter can be found by clicking here.   Feel free to comment!

July 2, 2012

Mr. Richard Boornazian
Assistant Commissioner for Natural Resources
Department of Environmental Protection
401 East State Street
P.O. Box 402
Trenton, New Jersey 08625-0402

Dear Rich:

You had asked Michele Byers if I would forward my thoughts regarding habitat restoration at Bull’s Island.

I would like to preface my comments by placing the Bull’s Island project in context. New Jersey Conservation Foundation has been advocating for protection of the Delaware River and its island habitats for decades, and has been helping state, county, and municipal governments acquire and protect many of them, from Petty’s Island near Camden, to Burlington and Bordentown Islands near Trenton, to the many islands in Hunterdon County. These Delaware River islands have had all sorts of varied uses over the last few centuries, but now many are forested and contain important migratory bird habitats. The forest at Bull’s Island is the most ecologically significant of any of the Delaware River islands, and it is also one of a handful of sites in all of New Jersey where old-growth characteristics are present in the forest. Finally, it is a unique breeding location for two rare warbler populations.

My conclusions are derived from 33 years of experience in examining and measuring forest structure in floodplain forests along major rivers from the Raritan and Delaware River in New Jersey to the Mississippi and Wisconsin Rivers in Wisconsin:

  •  If clear-cut, restoration in any of the relatively flat portion of the floodplain forest at Bull’s Island will almost certainly fail. Once the camping facilities are removed, the forest area should be added to the Bull’s Island Natural Area.
  • Low-cost restoration can be attempted along a few of the severely eroding or bare riverbanks, especially at the D&R Canal inlet, but even in these places the intensity of the floods is likely to render any restoration work moot.

The basis for my conclusions is as follows:

Habitat restoration can only be considered in the context of a full ecological understanding of habitat life history and the physiognomy of floodplain forests. The floodplain in the northern portion of Bull’s Island State Park is a unique natural feature, being one of the few places left anywhere in New Jersey where a mature forest is expressing old-growth ecological attributes. The ecology of a mature floodplain forest on sand and gravel levees, like at Bull’s Island along a major river in the northeastern US, is controlled by 2 kinds of natural floods:

  • yearly spring floods that are somewhat predictable in scope and frequency based on snowmelt, and often contain damaging ice floes.
  • random floods from extreme storm events that can be incredibly violent and even create new sand and gravel levees and change the shape of floodplain islands.

On occasion, a few years without a scouring flood will allow for the establishment of forest trees, whose roots reach down through the sand and gravel of the levee into the water table of the river. Although the brief periods of quiet, stable soil conditions that allow for the establishment of forest are infrequent, once established these forests grow quickly since their deep roots have access to the water table. Individuals of these species can persist for long periods of time, as they either have the ability to send up multiple sprouts to recover from flood damage, and/or buttressed trunks that are resistant to toppling.

The tree species that are the most tolerant of deep flooding and periods of anoxic conditions, scouring and/or deposition of soil, and extended drought at and near the soil surface are those that form the canopy at Bull’s Island today, especially American sycamore, silver maple, hackberry, and other typical floodplain species. The forest is characterized by widely-scattered giant trees with very wide crowns, numerous herbaceous perennial and annual species like smartweed and jewelweed, but a relative scarcity of true woody shrubs, since short, shallow-rooted woody species cannot resist scouring floods and ice floes. Box elder, a smaller, multi-stemmed tree, is the only common woody plant that persists low in the flood damage zone, as it can tolerate incredible damage near ground level.

Vines replace low-growing, woody shrubs and small trees in the floodplain ecosystem, as flooding is the dominant influence on the architecture of the floodplain forest. Floods scour away woody shrubs and tree seedlings, but typically vine species may successfully reach a supporting tree where they sometimes persist through a scouring flood and become established. The giant, deep-rooted floodplain-adapted trees with wide canopies and multiple trunks host many species of vines; in fact most tree species with exfoliating bark worldwide, like the American sycamore at Bull’s Island, are floodplain species. The exfoliating bark trait is thought to be an evolutionary response to resist colonization by vine species.

As discussed on page 152 of “The Vegetation of New Jersey” (Robichaud & Buell, 1973), the mature, old-growth characteristics on display in the Bull’s Island forest have been held in special regard for decades. Rare birds that require the high, mature riparian canopy breed there (albilora race of the Yellow-Throated Warbler, extremely rare in the northeast and a disjunct, evolutionarily-important population, and the declining Cerulean Warbler). As a result of the unique forest structure and species assemblage, the southern half of Bull’s Island was designated as a state Natural Area. Had the public campground not pre-dated the New Jersey Natural Areas System designation, it is likely that the northern section of Bull’s Island would have also been designated a natural area.

Now that the campground will be removed, the asphalt roadways should also be removed and allowed to proceed through natural succession. The northern portion of the island should be added to the Bull’s Island Natural Area. Hiking can easily be accommodated along the adjacent D&R Canal Towpath, and if camping is in demand, many new state park acquisitions in the immediate area can be utilized in safety, outside of the Delaware River floodplain.
We do not support the removal of the mature forest at Bull’s Island. We do not believe that any restoration plan for the island has a reasonable or decent chance of success. As described above, floods will dictate what happens at Bull’s Island, and restoration efforts will be futile. Plantings cannot be protected from deer, as any attempt at fencing will be destroyed by floods. The droughty sand and gravel soils will make successful establishment of plantings highly unlikely, as there are extended droughts and heat waves every summer. Deep raging floods will likely scour away any plantings before they are established.

Inexpensive attempts at stabilizing the eroding riverbanks at Bull’s Island, especially at the inlet of the D&R Canal, could be considered. Since repeated severe floods limit the chance for any restoration success, the re-establishment of vegetation on steep banks must be low cost. Along the steep banks of the D&R Canal, shoots of native willows (genus Salix) could be inserted in an attempt to stop soil erosion. With luck, a window of time might pass and allow the willows to establish. Eventually, if a fairly stable willow thicket were to form, plenty of sun could still filter through the narrow leaf blades of the willows, providing appropriate habitat for the native trees at Bull’s Island to colonize the riverbanks. This process would mimic the natural ecological succession that takes place when sand and gravel islands are either swept clean or form anew in raging rivers like the Delaware.

The existing forest at Bull’s Island is the best possible habitat for protecting significant rare elements of our native New Jersey biodiversity, keeping the dynamic island as stable as possible, resisting erosion and sedimentation in the D&R Canal, and regenerating itself naturally with locally-adapted species as gaps form. The forest is mature; a tree will topple occasionally due to the natural stresses of living in a dynamic floodplain, as they have been doing for at least half a century. In 2011, a series of severe storms resulted in high rates of trees falling all over central, western, and northern NJ, creating incredible havoc. In comparison, Bull’s Island fared well, as few large trees fell despite the tumultuous conditions. This is because major floods have been removing trees at a relatively constant rate for decades at Bulls Island. Despite having buried roots and other stresses, the canopy trees at Bull’s Island are well-adapted to the physical stresses of living along a major river floodplain.

Once the campground facilities and asphalt paths are completely removed, except for the access road required for work along the D&R Canal, the remainder of the northern portion of Bull’s Island State Park should be added to the existing Bull’s Island Natural Area.

Thank you for considering our comments regarding Bull’s Island. We would be happy to discuss our conclusions with you further.


Emile DeVito, Ph.D.

What better way to address some of the philosophical and practical issues facing land managers in New Jersey than collaboratively developing a land management plan for a spectacular property? The next Stewardship Roundtable meeting will be held on April 18, 2012 at Ridge and Valley Conservancy’s Gnome Hollow Preserve.  This will be a “working” meeting where we will help Ridge and Valley Conservancy develop a Forest Stewardship Plan for this gorgeous preserve.   If you haven’t been in the woods in this part of New Jersey, you are in for a treat.  

The meeting will start at 10:30 10:00 and go until 1:30 PM.  We will meet at  Johnsonburg Town Hall (Frelinghuysen Township), Route 661 (Main Street), just west of the intersection with Route 519.  Ridge and Valley will be providing lunch, but you are also welcome to bring your own.

Click here for a link to a Google Map to get directions.  Note that this map also shows the property shapefile, so if you end up late you can meet us there instead.  

Please RSVP to me directly at so we know how many people are attending.

This is how Ridge and Valley describes Gnome Hollow  on their website:

…[it] is primarily deciduous hardwood forest, but it contains a small former Christmas tree farm.  Ms. Johansen sold trees and gave the proceeds to charity.  The property has a mix of native hardwoods, including mature oak and black birch, hickory, and emerging sugar maple.  Several vernal pools, which flood in spring then drain in summer, are found throughout the forest. These pools are important habitat for reptiles and amphibians, which can breed in them without having fish, eat their egg. The vernal pools are also important recharge areas for the aquifers.

RVC is in the process of developing a forest stewardship plan for the property to help demonstrate how landowners can manage local woodlands for maximum conservation value and forest health.  Plans call for thinning of the Christmas trees to allow development of individual trees, encouragement of sugar maples on south-facing slopes to develop a “sugar bush,” such as those used in sugar mapling, controlled burns, and reintroduction of native trees, especially near vernal pools.  There is a trailhead on the property at Stillwater Road. The preserve is open from dawn to dusk, but nighttime use is permissible if one notifies RVC.

Here are a set of planning maps that I put together.  Click on the link here or the image below to download them.

Gnome Hollow Map Set 1

Here is the Google map:

The NJ Forest Fire Service Conducting a Prescribed Burn at Schiff Nature Preserve, 2/27/2012

It is prescribed burning season again!  The Daily Record did a nice article on the prescribed burning work we are doing at Schiff Nature Preserve.  Click here to read the article.  

We burned about 35 acres on Monday and hope to do another 65 or so by the end of March.  About 30 acres consisted of mature, eastern hardwood forest while the remaining 5 acres we burned was a portion of a larger warm season grass meadow.

Prescribed burning is a critical tool for forest stewardship and ecological restoration.  Not only does it  reduce wildfire risk, it is probably the only practical and cost-effective way to control widespread non-native invasive plants.  It is pretty obvious that the non-native invasive plants that are so prevalent in many parts of New Jersey are not palatable to deer, while native plants are.   This gives non-native invasives a competitive advantage; where overabundant white tailed deer are chomping away on natives, the invasives grow instead. 

At the same time we aggressively reduce deer densities at Schiff, the prescribed burning we do reduces non-native invasive plants and therefore opens up growing space for regenerating trees and native understory plants.  There are several species of native trees, including Northern red oak (New Jersey’s state tree!), that are dependent on fire or other disturbance for regeneration.

The New Jersey Forest Fire Service is the state agency that conducts prescribed burns for us.  Unfortunately, they are under the same budgetary pressures as the rest of DEP.  We need to figure out a way to get more resources to these land management agencies if we are going to address the major conservation threats we face today in New Jersey.

Here are two articles that are part of the excellent “Grassroots” series by the Daily Record about conservation issues in New Jersey:

Saving songbirds: Sparta Mountain project an effort to lure golden-winged warblers

GRASSROOTS INTERVIEW: New Jersey forests once a crowded stage for crooning golden wings

What NJ Audubon and the Division of Fish and Wildlife have done is use ecological forestry concepts to create habitat for the imperiled golden winged warbler at Sparta Mountain Wildlife Management Area.  Although this type of active stewardship activity has the potential to be controversial in New Jersey, collaborating with partners can make all the difference.  Kudos to NJ Audubon and the Division of Fish and Wildlife for this excellent project!