Japanese Knotweed Treatment Seminar

Japanese Knotweed Treatment Seminar 2021-10

Japanese Knotweed, a non-native invasive plant that spreads aggressively,  degrades property values as much as it degrades native ecosystems.  Forming a ten-foot tall ever-spreading  mass, Fallopia japonica prevents native plants from growing, yet provides little to no benefit to wildlife.  Japanese Knotweed is difficult to dissuade, let alone eradicate.  Yet hope remains – learn what to do, and when to do it, at our first Japanese Knotweed Treatment Seminar:

Why it’s imperative to control Japanese Knotweed

Like other aggressive invasive plants, Japanese Knotweed must be actively managed.  Japanese Knotweed quickly forms a monoculture, reducing biological diversity and lowering the quality of our streams and rivers.  Once Japanese Knotweed establishes itself, habitat degrades in quality, streambanks erode, and species diversity declines. 

Once well established, control requires a well-timed plan of annual treatments for up to five years.  If control is not attempted, Japanese Knotweed will spread to the exclusion of all other species. 

Japanese Knotweed – Landowner Assistance Project

One landowner, working alone, contributes to the health of the ecosystem by combatting invasive plant species – but neighbors working together, and combining efforts with environmental and municipal entities, can accomplish massive improvements.  The CFC will coordinate a several-years’ program to connect parcels together, and to advocate for and assist with control treatments.  This October’s Japanese Knotweed Treatment Seminar is the first step to improving the health of our Wild & Scenic Clarion River. 

Landowner Participants benefit from: 

  • expert information and guidance, including creation of a treatment plan, and recommendations on chemical formulations;
  •  access to high-quality equipment, or the option to hire vegetation management contractors in a block;
  • help monitoring progress and reporting local infestations; and
  • advice on re-establishing native habitat

Please join us for this first round meeting – and bring a neighbor! 

Tuesday, 5 October 2021 – 5 pm >>
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We’ll be at MacBeth’s Store & Cabins, located at the Route 36 bridge in Cook Forest State Park, at the Clarion River.  Google maps addresses: 15361 PA-36, Cooksburg, PA 16217, or 8QHR+VG Cooksburg, Pennsylvania.

This Japanese Knotweed Treatment Seminar is free – no registration required.  We’ll be outside, but please bring a coronavirus mask if you wish.  NB re CORONAVIRUS: By attending, participants assume responsibility for any and all risk due to possible exposure to COVID-19. Please DO NOT attend if you have been exposed to someone with COVID-19 in the last 2 weeks.

This event is a collaboration of the Cook Forest Conservancy, Penn State Extension, the Clarion County Conservation District, the DCNR of Cook Forest State Park, and the McKean County Conservation District, as part of their work on invasive plant management under the Allegheny Forest Health Collaborative

Remind yourself about the event via Facebook, and send us any questions:

Japanese Knotweed - Clarion River - September seed pods
Japanese Knotweed - Clarion River - September seed pods

Hemlock Pests and Diseases

Hemlock Pests & Diseases

Hemlock Woolly Adelgid (HWA) is a powerful predator of these integral trees, but unfortunately it is not the only serious threat to hemlock ecosystems. Hemlock trees battle a variety of other insect pests, and can be beleaguered by diseases – here are a few of the more formidable.

Threats to Hemlock Trees:

Threats to Hemlock Trees - Dale Luthringer, Cook Forest State Park

Elongate Hemlock Scale

Elongate hemlock scale, a tiny insect with an oval hard cover, or “scale,” is brown or white, and attaches on the undersides of needles seemingly at random.  This pattern is different from HWA, which lines up near where needles are attached to the twig. It sucks out juices, weakening the tree.

The elongate hemlock scale is particularly devastating to hemlocks already affected by HWA or drought, and often arrives after HWA has been found in the area. This “one-two” punch of two invasive insects is extremely difficult to treat, requires a great deal of labor and costly chemicals, and ultimately reduces the numbers of hemlocks that can be saved. 

the Hemlock Looper

The hemlock looper moth (Lambdina fiscellaria), a/k/a the mournful thorn, is a native insect which has “very long pectinations resulting in a conspicuously feathery antenae.” This little bug can severely defoliate hemlock during high population phases, and also damages balsam fir, white spruce, oak, and other hardwoods.

the Spruce Spider Mite

These rapidly-reproducing, warm-weather-loving arachnids use “piercing-sucking mouthparts [to] withdraw sap containing chlorophyll from the needles” of conifers, which don’t recover once damaged.  “Infested needles become mottled and appear yellowish to gray in color,” and are commonly in groups low and on the inside of plants. They’re not terribly easy to kill (use miticide, not insecticide), so read this informative Penn State Extension article if you worry about a spruce spider mite (Oligonychus ununguis) infestation.

the Hemlock Borer

The hemlock borer (Phaenops fulvoguttata, f/k/a Melanophila fulvoguttata) prefers to attack when a hemlock has already been weakened by other pests, disease, or drought.  The best defense against these destructive bugs is maintaining healthy hemlocks.  

Click here for more information on the hemlock borer – USDA Forest Service “Pest Alert,” Aug. 2000.

hemlock borer insect
PA DCNR - Forestry ,

Signs of hemlock borer infestation include:

  • small oval holes in the bark, about 3mm in diameter, [from which] beetles have emerged;
  • larval galleries on the surface of the sapwood, beneath the bark;
  • woodpecker damage may indicate heavy infestation with larvae; and
  • bark chips piled at tree bases indicate the same.

Needle Rust

There are several types of rust affecting hemlocks.  No treatment is usually needed, but you can identify hemlocks infected with needle rust by spotting that “current-season growth is slightly swollen and curled, [and] orange-yellow spores coat the infected tissue.”  

Sirococcus Tip Blight

The dying off of new growth resultant from this blight could pose a great risk to hemlocks, which increases in prevalence during prolonged wet weather and in very moist sites.  Northwestern PA seems to have a higher than usual occurrence.  Treatment includes pruning to increase air flow. 

Climate Change Threats

While neither pest nor disease, it’s worth noting here that hemlocks are also intolerant to drought.  Weather patterns of late have shifted, becoming less even and predictable.  Pennsylvania has witnessed several years of long dry periods punctuated by strong storms, the water of which falls too heavily for proper saturation into the soil.  Dry, warm winters benefit the HWA, while weakening the trees.  

The hemlocks of Cook Forest are less impacted than those of the Smoky Mountains primarily due to environmental factors:  the southern environment more strongly favors HWA.  While the southern hemlocks sickened more quickly, northern hemlocks held on while science worked on “vaccinations,” and our occasional cold winters knocked back HWA infestation levels. 

How to help hemlocks

Improve the health of all your trees:

  • plant and encourage a biologically diverse property – trees with unrelated but nearby neighbors are often healthier 
  • invite and protect pollinators, both bird and insect
  • plant natives 
  • insist on local stream and riparian health protections
  • reduce pollution:  gasoline, exhaust, consumer pesticides; minimize lawn
  • monitor your trees for stress or disease, and act early 
  • protect roots from soil compaction (e.g., don’t park or drive  under tree canopies)

The majority of this presentation is courtesy of Dale Luthringer, Environmental Education Specialist, Cook Forest State Park – with thanks for his gracious permission and his time, from the CFC.  

Do you think your hemlock is afflicted by pests or diseases?  For specific questions on hemlock health issues, please contact your DCNR Service Forester, or the PA Bureau of Forestry

Pennsylvania Invasive Plant Information

Penn State Extension has released updated guides to the invasive plants of Pennsylvania — these are excellent free info for landowners struggling with non-native plants taking over their properties.  

A synopsis of the threats posed by these invasive plants, from the Invasive Plant Sheet Series announcement:

The term “invasive” is used to describe a plant which grows rapidly, spreads aggressively, and […] degrade native environments by causing a decline in native plant species diversity. They degrade wildlife habitats for native insects, birds, and other wildlife and threaten rare species. In addition, invasive plants have been shown to inhibit forest regeneration success, and slow or halt natural succession. Once well established, invasive plants require large amounts of time, labor, and money to control or eradicate.

Invasive Plants of Pennsylvania

Japanese Knotweed - Invasive Plant in Pennsylvania - photo by Dave Jackson
Japanese Knotweed - Invasive Plant in Pennsylvania - photo by Dave Jackson

Once Pennsylvania landowners learn how to ID these invasive plants, they can effectively “implement control measures to help prevent further spread and habitat degradation,” hopes David Jackson, Penn State Forest Resources Educator, and co-author on many of the species sheets.

Direct links to the species most problematic in the Cook Forest State Park area are in the bullet list above – or find an links to all the invasive plant species fact sheets via the button above.   

Even MORE information, including the most effective methods of control, are indexed at the Penn State Extension Invasive & Competing Plants page

HWA Treatment Seminar – 14 Sept 2019

2019-09-14 CFC BOF HWA Seminar Cook Forest

HWA kills trees - Protect your Hemlocks!

Learn more about the threat, and how to treat your own trees.  This event is free to all – held at 2 pm on Saturday, 14 September, 2019, at the new Cook Forest State Park office, 100 Route 36, Cooksburg, PA 16217.  It will follow the member’s picnic and history walk hosted by the Woodland Owners of Clarion-Allegheny Valley.

Join specialists on invasive insects from the PA Bureau of Forestry for information on at-home treatment for Hemlock Woolly Adelgid (HWA), including:

  • the importance of helmock
  • the reduced cost of treatment (far less than removing dead trees!)
  • different treatment methods, including:
    • overview of available pesticides;
    • which is best for a given situation; and
    • the best seasons for treatments

followed by an on-site session during which attendees can actually apply the treatment – this single application should protect each target hemlock for seven years!

We’ll be walking along Tom’s Run for the field work – please wear long pants and closed shoes; gloves will be provided.  Attendees may be able to loan equipment from the PA Bureau of Forestry for treating their private hemlock stands – more details at the event. 

Download a printable copy of the event PDF here

a WOCAV event: Herbicides for Invasives

Herbicides for Invasive Plants

FREE seminar & field workshop – Saturday, 24 August 2019 – nine to noon @ the Rimersburg Rod & Gun Club.  Join the WOCAV, with experienced forestry heribicide specialists Dave Jackson of Penn State Extension & Bryan Rose of ArborChem for information on how, when, and why to treat some of our most problematic plant species. Agenda:

  • Silvicultural Considerations: Competing vegetation impacts. Why do we have so much of it? When is treatment necessary? Why Herbicides?
  • Products and equipment, labels, & required PPE – How to protect yourself from exposure.
  • Overview of Application Methods – Broadcast applications (Band), spot treatments, hack and squirt, basal bark, and stump treatments, recommended rates, and calibration for band treatments
  • In woods demonstrations: competing and invasive plant control applications

442 E Rod and Gun Club Rd, Rimersburg, PA 16248