Japanese knotweed (Polygonum cuspidatum; Latin synonym Fallopia japonica) is indisputably a major nuisance in the urban forest. NYC Parks Natural Resources Group has documented extensive research and control methods they’ve used, in partnership with the Bronx River Alliance and other entities, to combat knotweed along the Bronx River and in other natural areas in the City’s five boroughs.
Regardless of what combination of chemical and mechanical means are employed, control of Japanese knotweed is widely acknowledged to be imperfect at best. While we can and should manage its presence in our urban forests, this plant is here to stay.
Why and how is Japanese knotweed so successful at colonizing the most degraded sites? Why is it so hard to control? And what are some of the positive attributes of the plant that you might not hear much about? In this piece, Council member Laura Wyeth, a horticulturist with a particular interest in weed science, explores some of what makes Japanese knotweed unique.
Japanese knotweed is a plant caught up in the polarization of our times. Both its virtues and its malevolence have been inflated in the public imagination, and it is at once known as both miracle drug and botanical monster. In Canada, a nation not prone to paranoia, it has been described as “a demon weed so relentless, bloody-minded and destructive, it’s been called the terrorist of the plant kingdom.” Strong words for a creature with no teeth, claws, or toxicity to humans. Internet herbalists tout its miracle cancer-fighting properties with equal hyperbole. Yet with this plant, the quiet facts are more interesting than the hype.
Some blog posts resonate long past their original publication date date. Transplanting and a Deeper Look at “Fall Hazards” was one of the top five posts in 2015 and was the second most viewed post in 2016. Former NYC Director of Street Tree Planting Matt Stephens and Taking Root Editor Michelle Sutton coauthored this story questioning commonly held beliefs about “fall hazards,” mostly as it applies to B&B trees, but they also discuss the interaction of the fall season with other production methods, like bare root. Nina Bassuk helped craft the section called “The Five Branches of Transplanting Success,” which should be of interest to anyone planting trees.
Kristy King and NYC Forest Restoration: Dreaming Big for the City’s Natural Areas Many readers wanted to learn about the work of the NYC Natural Resources Group, which manages 5,000 acres of forested natural areas across the five boroughs of NYC, and about Director of Forest Restoration Kristy King. Her dream for NYC: “… that all forested areas are dominated by native species and that invasive species have been managed to the point that natural forest regeneration is occurring and that the public holistically values the natural resources in their area.”
NYSDEC Urban Forestry Intern Jennifer Kotary: Get to Know Her! Many blog readers were keen to know about this dynamic up-and-comer. “My internship research involved in-depth exploration of what communities are doing to protect and build green infrastructure across the state. Via Mary’s [Kramarchyk] assigned projects, I was able to produce tangible evidence that there is quite the statewide collective will to plant and nurture an expanding canopy as well as many career and volunteer opportunities to do so.”
SMA’s 2016 Urban Tree of the Year: Musashino Zelkova generated a lot of buzz. ‘Musashino’ has been a successful and popular street tree for many more years in Japan, proving itself useful as a narrow, upright form of zelkova. It can tolerate drought and heat and is pH adaptable and pollution tolerant. See a list of all the past SMA Urban Trees of the Year here.
Gary Raffel: Get to Know Him! Gary has served the Council in a variety of capacities, including as a board member. “I started Dynamic Tree Systems in 2002, offering general tree care service as well as Plant Health Care and Integrated Pest Management programs. I later wanted to find a niche in the industry and purchased a Tree Radar Unit at a time when there were only three of us in the U.S. and eleven people in the world using the equipment. A few years later I became the company’s international trainer, such that when a new unit was sold I would fly to the particular client and spend a week training them on their new equipment (I still do that, in addition to Dynamic Tree Systems).”
Trees for Tribs, as in tributaries, is a Department of Environmental Conservation program replanting New York’s streams. The program began in 2007 in the Hudson River Estuary and has since expanded statewide, working with partners across the state to plant native trees and shrubs for improved wildlife habitat, water quality, and storm resiliency.
The program works with private landowners, municipalities, schools, and conservation organizations, providing technical assistance, low- to no-cost native trees and shrubs, and tree tubes for planting sites. The program currently has coordinators on the ground in six watersheds (Champlain, Mohawk, Hudson Estuary, Croton, Upper Susquehanna, and lower Genesee). Trees for Tribs works with other organizations outside of these watersheds to coordinate projects on the ground.
This story comes to us from Bronx River Alliance Deputy Director Maggie Greenfield and Natural Areas Conservancy Communications and Public Outreach Manager Nicole Brownstein.
The Bronx River has seen its fair share of history. It was first called the Aquehung, or “River of High Bluffs” by the local Native Americans. Two tribes, the Weckquaesgeek and Siwanoy, drank the river’s water, fished along its banks, and hunted in the surrounding woods. The river also held a spiritual significance for them and was a place for ritual baths each year. Jonas Bronck arrived in 1639, brokered a deal with the Native Americans for 500 acres along the river, and turned it into farmland.
Mills sprang up along the river, harnessing its energy and using it as a natural flowing sewer system. As the manufacturing industry fell into decline and the mills began to disappear, the river remained a dumping site for the surrounding communities. This was before we fully knew or cared about the effects of industrial and residential waste dumping.
It wasn’t until the environmental movement picked up in the mid-1970s that the restoration process began along the 23-mile river. In the late 1990s, the Bronx River Working Group was founded, with more than 60 community organizations and businesses combining efforts to orchestrate work along the river. The spirit of this effort led to the creation of the Bronx River Alliance, a group dedicated to restoring the waterway. When they began their work, these activists found objects as bizarre as refrigerators, tires, and even a wine press in the river. Today the river’s health is returning, evidenced by the long-awaited appearance of river herring, American eel, eastern oyster, and beavers. But our work is not yet done.
Landowners Can Take Advantage of Low-Cost Native Plants; Available to Schools for Free
More than 45 species of trees and shrubs from the New York State Department of Environmental Conservation’s (DEC) Saratoga Tree Nursery are now available to public and private landowners and schools, DEC Acting Commissioner Basil Seggos announced today.
“The seedlings from our Saratoga Tree Nursery help landowners create habitat and improve air and water quality in their backyard and schoolyard” Acting Commissioner Seggos said. “In addition, many types of trees and shrubs provide important food sources for bees, butterflies and other pollinating insects which have declined over recent years. I encourage all New Yorkers to take advantage of this great resource, and to work with our foresters and experts at the nursery to maximize the conservation benefits of your plantings.”
Low Cost Options for Public and Private Landowners
The program provides low-cost, native planting materials from New York sources to encourage landowners to enhance the state’s environment for future generations. The Saratoga Tree Nursery also offers a few non-native species which can enhance wildlife plantings and assist with stream bank stabilization. For instance, toringo crabapple provides a winter food source for wild turkey, grouse and deer while streamco willow is used in many stabilization projects.
Species attractive to pollinators and offered by the nursery include maples, sycamore, buckeye, willows, bristly locust, roses, viburnum (highbush cranberry, arrowwood, nannyberry), dogwood, crabapple, sand cherry, buttonbush, wild grape, and, black cherry.
The Saratoga Tree Nursery sells primarily bare-root stock for direct plantings, but a few species are available as containerized stock. Landowners can receive planting advice from their nearest DEC forestry office or private forestry consultant. The 2016 Tree and Shrub brochure (PDF) (170 KB) can be found on the DEC’s website or by calling the Saratoga Tree Nursery at(518) 581-1439. Some species sell out quickly.
Kristy King is the Director of Forest Restoration for the Natural Resources Group of NYC Parks. Here we get to know Kristy and the work that her department does to bring degraded land back to life in the surprisingly diverse range of natural areas of New York City.
Can you tell us about your childhood influences that foreshadowed getting interested in forest restoration work? Kristy King: I’ve always been interested in biology and used to explore the woods and streams behind my house in Columbia, SC. I can’t say that I was on track to work in forest restoration from a young age, but I’ve always been fascinated by the outdoors and felt that nature is an important part of the human experience. When studying biology in high school, ecology fascinated me the most due to the profound interconnectedness of life and the environment. I was so blown away by the complexity of it all and knew I wanted to dig deeper.
Can you tell us about your educational and career trajectory? King: I studied Biology (focus on botany and ecology) at the College of Charleston in South Carolina and graduated in 2003. At that point I felt unsure about my trajectory and worked for some months as a florist and a field assistant performing vegetation surveys in the cypress swamps of Francis Marion National Forest, north of Charleston.
I then scored an entry level job with NOAA/National Ocean Service as a marine biologist (basically a lab technician) studying the ecological impacts of harmful algal blooms. I did that for three years and while it was very cool, I didn’t feel personally invested in the field and didn’t want to work as a laboratory scientist for my entire career.
I started independently exploring subfields in ecology and was quite taken by urban ecology both because I personally wanted to live in a big city and because I felt excited about the potential impacts of performing science and management where so many people live!