non-native invasive plants

NJ Invasive Species Conference

Click image above to download pdf version of conference agenda.

This is a wonderful opportunity to learn about non-native invasive species in New Jersey.  Experts will talk about the newest emerging threats, best management practices, and the latest biocontrol initiatives.  Roundtable discussion in the afternoon are geared toward digging deeper into these topics.

To register, click here.  

Hope to see you there!


Here is the final version of the Stewardship Roundtable Do Not Plant List. I’ve been sitting on it for a few months now and realize that I’ve done all I could on it. If anyone feels strongly about amending it, recontextualizing it, or adding to it in the future, I’m completely open to that – it should just be discussed within the Roundtable.

In the meantime, I hope that the list has utility all around for those many times when such a list comes in handy.

~Jared Rosenbaum

Do Not Plant!

Frequently Utilized Invasive Exotic Plants in New Jersey

New Jersey Stewardship Roundtable

Invasive exotic plant species degrade the health and function of local ecosystems by displacing native plant species and associated wild fauna.

The species below, and cultivars thereof, are not appropriate for use in landscape plantings within the State of New Jersey. The following non-native plant species are still available in nurseries and are used in landscaping. They are aggressive colonizers of natural areas within the state of New Jersey.

The list below focuses on species still available within the horticultural trade, and does not include several widespread invasive plant species which are not currently planted, e.g. Japanese stiltgrass (Microstegium vimineum).

This resource was created by the New Jersey Stewardship Roundtable, an association of groups dedicated to stewardship, ecological restoration, land preservation, public parks, local agriculture, and related environmental conservation and advocacy.

Acer ginnala Amur maple
Acer platanoides Norway maple
Acer pseudoplatanus sycamore maple
Actinidia arguta hardy kiwi
Aegopodium podagraria goutweed
Ailanthus altissima tree of heaven
Akebia quinata chocolate vine
Albizia julibrissin mimosa tree
Ampelopsis brevipedunculata porcelain berry
Aralia elata Japanese angelica tree
Berberis thunbergii Japanese barberry
Buddleja davidii orange eye butterflybush
Celastrus orbiculatis Oriental bittersweet
Clematis terniflora Japanese clematis
Cynanchum louiseae black swallowwort
Eleutherococcus sieboldianus fiveleaf aralia
Eragrostis curvula weeping lovegrass
Euonymus alata winged euonymus
Euonymus fortunei winter creeper
Frangula alnus glossy buckthorn
Hedera helix English ivy
Humulus japonicas Japanese hops
Iris pseudacorus Yellow iris
Koelreuteria paniculata goldenrain tree
Lespedeza cuneata Chinese lespedeza
Ligustrum amurense Amur privet
Ligustrum obtusifolium border privet
Ligustrum ovalifolium California privet
Ligustrum vulgare European privet
Lonicera caprifolium Italian honeysuckle
Lonicera fragrantissima fragrant honeysuckle
Lonicera japonica Japanese honeysuckle
Lonicera maackii Amur honeysuckle
Lonicera morrowii Morrow’s honeysuckle
Lonicera tatarica Tatarian honeysuckle
Lythrum salicaria Purple loosestrife
Malus toringo Japanese crabapple
Miscanthus sinensis Chinese silvergrass
Myriophyllum aquaticum Parrot feather
Pachysandra terminalis Japanese pachysandra
Parthenocissus tricuspidata Boston ivy
Paulownia tomentosa princess tree
Phellodendron amurense Amur corktree
Photinia villosa Oriental photinia
Polygonum orientale kiss me over the garden gate
Pyrus calleryana Callery pear
Ranunculus ficaria lesser celandine
Rhamnus cathartica common buckthorn
Rhodotypos scandens jetbead
Rosa multiflora multiflora rose
Rosa rugosa rugosa rose
Ulmus parvifolia Chinese elm
Ulmus pumila Siberian elm
Viburnum dilatatum linden viburnum
Viburnum lantana wayfaring tree
Viburnum plicatum Japanese snowball viburnum
Viburnum setigerum tea viburnum
Viburnum sieboldii Siebold’s viburnum
Vinca minor common periwinkle
Wisteria floribunda Japanese wisteria
Wisteria sinensis Chinese wisteria

A friend just forwarded me an interesting report from the Environmental Law Institute called Status and Trends in State Invasive Species Policy, 2002-2009. I haven’t read through the entire thing yet, but it is good to see how New Jersey compares to ten other states that have invasive species councils. I am somewhat comforted by the fact that NJ has an invasive species council and a comprehensive invasive species management plan.   However, the report points out that:

New Jersey has made no significant changes
to its laws and regulations related to invasive
species in recent years.

In the absence of state level laws, regulations, and resources, non-profit conservation organizations and particularly the Central Jersey Invasive Species Strike Team (CJISST) have begun to do a great job carrying out some of the recommendations of the comprehensive invasive species management plan, particularly as it relates to new, emerging invasive species.  It is clear, however, that in order to really get a handle on this problem we will need state laws and regulations as well as resources that only state government could provide.

I’d love to hear your comments about the report after you get a chance to read it.

Here is a great article on the restoration taking place at South Mountain Reservation.

As I mentioned in a previous post, I can’t say enough about how impressed I am by the conservation leadership of the South Mountain Conservancy, Essex County, Joseph DiVincenzo, and of course, New Jersey Audubon and New Jersey Conservation Foundation.

Note how expensive this is – $800,000.  If we were to measure the acreage of forests in NJ that need to be restored and multiply that by the per-acre costs of this restoration we’d have monetary value we could put on the ecological problem of overabundant deer.   This sounds like a fun exercise .  Anyone up for it?


Phillip Alampi Beneficial Insect Rearing Laboratory is seeking sites infested with mile-a-minute vine for presence of the Mile-a-Minute predator, Rhinoncomimus latipes and possible release sites.

If you have found Mile-a-Minute, you can send GPS data points to (instructions can be found here: Raw Data Spreadsheet). Note if presence of the biocontrol is suspected.

This biocontrol has already been released in NJ, and is present in central NJ. Plants having been attacked by Rhinoncomimus latipes are typically full of small holes.

Assessment Study by APHIS:

This information is from David A. Dick, Agricultural Weed Specialist, West Virginia Department of Agriculture

Here’s what we know (that I’m aware of):

1)      It occurs in at least 3 counties in WV

2)      It has also been found in Indiana

3)      There are areas where it has killed 100% of the stiltgrass present

4)      According to our plant pathologists, it looks like a fairly common fungal blight, although we are still trying to get a positive ID

5)      Similar symptoms are showing up on Jewelweed, deer tongue grass, and some sedges (not sure if it is the same pathogen)

6)      Likely spread as widely as it has due to a very wet spring, when most diseases get spread among plants.

That’s what we have so far.  The exciting part is that it is impacting stiltgrass.  However, it is probably not selective and has likely become abundant this year due to our spring weather patterns.

An online article with images (some included below):


Japanese angelica tree, Aralia elata

Initially, botanists had thought that New Jersey was experiencing a range expansion of a native southern species (Devil’s Walking Stick – Aralia spinosa).  Mary Hough had documented this species as “Rare” across most of New Jersey in her 1983 book “New Jersey Wild Plants”.  The Brooklyn Botanic Gardens Metropolitan Flora Project mapped the frequency of Aralia and had been set to write a paper regarding this natural spread of a southern species when they realized that they were actually seeing Japanese angelica tree (Aralia elata). [Note: This should be somewhat of a vindication for us non-botanists – even great botanists can have an ID issue!]

As you can see on the map from the link above, Japanese angelica tree is emerging rapidly and very possibly becoming a permanent fixture in NJ.  The Central Jersey Invasive Species Strike Team ranks it as “Emerging – Stage 3” meaning that we will only be targeting newly forming populations to contain its spread.  The species appears to be more common in northern New Jersey – we have only found several small populations and one large population in Hopewell Township — all will be eradicated in 2009 and we will keep up the searching for other populations. For control, we have been using basal bark applications of Garlon.

While thorny to the extreme, this species has very beautiful flowers and fruit that are attractive to birds.  It can mostly be found in sun or partial shade, but we have found that it can also tolerate full shade.

 For species identification informationinformation click here.