welcome to the CFC’s news & information database

In addition to current events and timely articles, this “news” page is meant to serve as an archive of information on all things forest — flora & fauna posts, camping & hiking tips, etc.  Whatever you’d like to learn or remember, please browse using the tags, or search.  

HWA Seminar for Landowners

HWA Landowner Treatment Seminar

Learn more about the threat posed by Hemlock Woolly Adelgid (HWA), and how to treat your own trees.  Scientists are making advancements in establishing populations of bio-control agents – the natural predators of HWA – but, for now, landowners should proactively protect their trees.  We’ll show you how: 

 HWA Seminar for Landowners

This event is free to all – held at 5 pm on Thursday, 7 October 2021, at the new Cook Forest State Park office, 100 Route 36, Cooksburg, PA 16217.  

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 hemlock trees
  • 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 the Clarion River for the HWA treatment field work.  Please wear long pants and closed shoes; gloves will be provided.  

HWA kills trees - Protect your Hemlocks!

Attendees may be able to loan equipment from the PA Bureau of Forestry for treating their private hemlock stands – more details at the event. 

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 >>
add event to your google calendar

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

Dendrology – Learn to Identify Forest Trees

a  Penn State Forest Stewards series article – written by Jim Finley, Professor Emeritus, Forest Resources Management, Center for Private Forests at Penn State.

Over the past year or so have you discovered a new or stronger connection to forests and trees? Those who study outdoor recreation have documented nearly explosive growth in the number of people exploring and spending time in parks and forests. Whether you are an old hand, used to spending time in sylvan landscapes, or a new convert to outside activities, have you found yourself looking in new ways at forests and wondering: What type of tree is that?

PAFS - Dendrology - identify forest trees

Forests are complex communities that depend on the interaction of the living (e.g., plants, animals, insects, fungi in soils) and non-living (e.g., soil structure, water, nutrients, weather, climate) components. Learning to identify, classify, and understand the role of each component’s contribution to forest function, health, and vitality describes the science of ecology, which seeks to understand and interpret these interactions. 

To Understand Forests, Learn Your Trees

The first step in understanding forests is to learn to identify common forest trees. Right now (mid-summer) is a great time to learn the trees in your local area, as we are at the peak of the annual growing season – leaves are mostly full size, and it is the easiest time in a tree’s seasonal life to identify individual species. 

Once you identify a species, say a red maple, which is the most common tree in the state, look around and recognize other individuals of that same species using the leaves as the principal characteristic for that species. Notice how individuals vary; obviously, they will differ in height and diameter. The bark on red maples of different size might look different. For red maple, the bark on smaller trees is smooth and silvery grey. As the diameter increases, small circular patterns with tiny potato chip-like raised bark flakes develop. On larger trees, this bark pattern will remain in place along with similar vertical flakes throughout.

Key Clues to Indentifying Tree Species

One of the tricks to the identification of any tree species is to recognize leaf types and arrangement.  For instance, white pine is the only tree which has needles in bundles of five

The second trick is to remember where you see the tree and then to visit it during the different seasons. When does it flower, show first leaves, drop leaves in autumn, and how do those events vary across the forest?

Identifying Trees: Books, Keys, & Apps

Dendrology “picture books” provide images of leaves, buds, and bark. Widely available and often region-specific, these allow you to match a given tree’s characteristics to the image.  These are useful in the field, where online resources and apps won’t operate.  

(CFC Editor’s note:  Another excellent resource is the Penn State Extension “Summer Key for Pennsylvania Trees,” a sort of science adventure method of dialing in on the species you’re studying by using visual clues.  The PDF is free, and can be sent to you phone, kindle, or tablet for offline field use. )

Firefly Forest Walk

Firefly Walk Cook Forest PA 2021-06

Let’s Explore: Cook Forest Firefly Walk

Over a dozen species of fireflies have been identified in the region.  Join scientists and the CFC  at twilight to search for several species of fireflies inhabiting Cook Forest’s various ecosystems.  This hike may possibly include the wondrous and elusive synchronous firefly, verified to inhabit the forests of the Pennsylvania Wilds only recently.  Learn about fireflies, and how to help protect their habitat. 

Following an educational presentation, we’ll be walking in the dark over uneven terrain, so bring your flashlights – red-light capable if possible.  There will be supplies to make a custom, removable red-light filter, so you can see better at night and disturb wildlife less.   Please also wear closed-toe shoes, and have a light jacket and a water bottle along.  

This event is FREE and open to all – however, this night hike is not ideal for children younger than middle-school age.  Donations will support the CFC and its Dark Sky initiatives.  To that end: 

>> Please, no photography, including cell phone cameras << 

Both fireflies and our eyes are photo-sensitive, and any white light is disruptive. Help us protect firefly habitat and their mating season by keeping all light to a minimum.

Firefly Forest Walk: 8 pm, Monday, 21 June 2021

in beautiful Cook Forest State Park, Pennsylvania.  The firefly walk is likely to last about three hours. 

This event is limited to 25 attendees – RSVP is required, either via the Facebook event linked here, or via email to info@cookforestconservancy.org.  The firefly walk meeting location and approx. GPS coordinates will be sent to registrants. Thank you! 

>> Weather Warning & Rain Date << 

Rain doesn’t deter fireflies, so the event will carry on as scheduled unless thunder & lightning occurs.  If there’s a thunderstorm on Monday, we’ll reschedule for 8:00 – 11:00 pm, Wednesday, 23 June 2021, at the same location. 

Temperature, however, does affect lighting bug lighting, so cooler temperatures mean less firefly activity.  Below about sixty degrees, we may not see any – so hope for a clear, warm, dark night.  

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; the DCNR of Cook Forest State Park; and Bruce Parkhurst, a very generous firefly specialist.

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 , Bugwood.org

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.”  

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

Ruffed Grouse and Winter

The state bird of Pennsylvania, ruffed grouse is a clever little game bird that’s very well adapted to winter.  Ruffed grouse is non-migratory, and even sleeps in self-made snow tunnels when conditions permit. Insulating feathers thicken around its nostrils, and around its legs, as fall temperatures drop. 

Most interesting, however, are the pectinations that appear – Professor Julian Avery, Penn State, photographed a ruffed grouse foot “in its winter ‘form’:”

Ruffed Grouse winter feet pectinations - by Julian D Avery
Ruffed Grouse feet in winter, showing pectinations - by Julian D Avery

Pectinations - Ruffed Grouse's Winter Feet

“During fall, they grow these pectinations, or comb-like structures, on the outsides of their toes. These modified scales help them tread on snow like a snowshoe does, and will fall off when spring arrives. Adaptations like these enable species to exist in all manner of crazy environments, and they also make a powerful argument for the conservation of biodiversity. Imagine the time and trial by selection it took to reach this solution, that not only helps them find scarce resources, but that is also in sync with the seasons.”
— Julian D. Avery

Pectinate:   having narrow parallel projections or divisions suggestive of the teeth of a comb

The pectinations on the winter foot of a ruffed grouse is an extension of the scales, made of cartilage, and not feathers. 

Snow Roosting: the Grouse Dive Bombs to Bed

Other adaptations include “snow roosting.”  When the snow is deep enough, and loose enough, a ruffed grouse will perch on a branch, choose its spot, and propel itself into the ground.  Widening its tunnel by waddling and winging a bit further, the grouse spends its night burning fewer calories and protected from wintry outside air and wind chill.  This snow-tunnel strategy also helps hide him from its bevy of predators:  goshawks, great horned owls, fox, and fishers.  Ruffed grouse are infamous for bursting explosively forth from these snow dens, another way to startle and evade predators, and hikers.  Learn more: 

Ruffed Grouse Society - Snow Roosting
Ruffed Grouse Society - Snow Roosting

Bonasa umbellus

Order: Upland Game Birds – Galliformes (incl. turkeys, grouse, chickens, quails, and pheasants)
Family: Upland Game Birds – Phasianidae (heavy, ground-dwelling birds)
Species: Ruffed Grouse – Bonasa umbellus

Mating ritual: drumming – a rapid beating of wings by the male
A group of grouse is a: covey

Ruffed Grouse - Ruffed Grouse Society instagram 2021-03-24
Ruffed Grouse - Ruffed Grouse Society instagram 2021-03-24

Conservation of Ruffed Grouse

Though currently designated a species of “least concern,” ruffed grouse populations have declined steadily for over three decades, primarily due to:

Habitat loss

Ruffed grouse particularly need early successional forest – the phase between field and saplings.  Grouse and woodcock were among those species that benefitted from the clear-cutting of Pennsylvanian forests in the 1800s, nesting in the downed treetops and grasses.  Ruffed grouse also needs mature forest – for winter shelter and forage.

Climate change 

As a species especially adapted to deep winter conditions, ruffed grouse is losing its evolutionary edge as our winters warm.  Poor or icy snow cover renders grouse more susceptible to energy depletion, predation, and freezing.

West Nile Virus

This mosquito-transmitted disease is reducing grouse numbers – and the Pennsylvania Game Commission has been tracking its “very high mortality” impact on our local population since its appearance in the early 2000s.  Warmer weather and stagnant water benefit mosquitos – save a grouse, eliminate standing water on your property.  Read more about West Nile in ruffed grouse:


the True Value of a Forest

Penn State Forest Stewards series article – written by Jim Finley, Professor Emeritus, Forest Resources Management, Center for Private Forests at Penn State.

Over the past year, as we have sought outdoor experiences, have our attitudes towards forests changed? For many, time in forests and woodlands provided solace and distance from others. These are seemingly disparate ideas seeking comfort in isolation when so many were pining for interactions with others. Regardless of individual intents, records and observations suggest the past year has drawn many to new outdoor experiences. As a person who has always looked for time afield in wooded landscapes, I wonder if the past year has changed relationships to forests, woodlands, and trees.
2021-03 PAFS article Jim Finley on the True Value of Forests

What did those individuals who initiated, restarted, or confirmed their affinity to sylvan landscapes think? What did they see? What questions did they have? Did they see a working forest or a preserved landscape?

To the last point, I will offer that all forests are working, even protected woodlands; for example, state and county parks are working. Public forests and private forests are working. They work as they create, deliver, and share diverse benefits.

A Working Forest is a Managed Forest

The forestry literature offers that a “working forest is actively managed to generate revenue from multiple sources, including sustainably produced timber and other ecosystem services, and thus are not converted to other land uses such as residential development.” This is a challenging definition.

The working forest definition is specific, imploring people to manage forests. What does this mean? A quick read would suggest the need to manage for traditional forestry products – trees, timber, logs, or pulpwood; however, it also allows for ecosystem services through forest management. Managing a forest to produces products involves decisions and action. Managing a forest for ecosystem services, such as water, air, habitat, or what are commonly considered non-market goods, offers a different perspective.

Hope for Hemlocks article

hemlocks over Cook Forest Longfellow Bridge

The Cook Forest Conservancy obtained permission from the author to link to this informative article, which summarizes the situation, the current science, and the programs and trials underway in the US to control HWA (hemlock woolly adelgid, an invasive insect) on Eastern Hemlocks, as of late 2020.  Cook Forest State Park is a priority area for HWA treatment, as both an exemplary old-growth area, and a National Natural Landmark – so our trees are in better shape than most.  HWA is currently in the forest, though, and we and all others in hemlock forests must remain informed and vigilant. 

Hope for hemlocks: New tactics found to fight deadly pest

by Ad Crable for the Bay Journal, 23 November 2020

The article bluntly sets forth the magnitude of the threat:

“Without intervention, most trees in natural settings will die,” according to [Pennsylvania’s] latest Eastern Hemlock Conservation Plan.

There still are an estimated 124 million hemlock trees greater than five inches in diameter alive in Pennsylvania. But that’s nearly 13 million fewer than in 2004, and the mortality rate has increased fourfold since 1989.

and emphasizes the importance of Eastern hemlock to hundreds of other species, and its unique and irreplaceable niche in the forest ecosystem.  For example, Hemlock groves provide cooling, filtering, and erosion control along streambanks, and their survival is essential for the survival of native trout, and the other organisms of Pennsylvania’s cold water streams.

The article succinctly covers the current methods of protecting hemlocks, from injecting chemical pesticides into the soil surrounding tree roots, to releasing varieties of beetles and sliver flies that predate on the HWA.  Scientists are studying stands of hemlock which appear resistant to HWA, and working on replicating this characteristic.

Science is working to help the hemlocks find a natural balance – to let the tree adapt to this non-native insect threat, or to bring in predators of HWA to keep its impact on hemlock health manageable – and to keep this valuable and venerable conifer in our forests.  Because, as Donald Eggen, forest health supervisor for the Pennsylvania Bureau of Forestry so aptly states:

When you walk through a hemlock forest, you are experiencing a unique habitat that is only found in a hemlock forest.

Moth infected with zombie fungus

zombie moth - insect infected with Cordyceps fungus

Poor Zombie Moth!

This moth has a fungus!  Spotted by the CFC on a hike near Cook Trail, this moth was identified by a PA Bureau of Forestry entomologist as likely having been infected with a Cordyceps fungus.

What this means for our hapless moth friend is – ultimately- mind control, followed by death.    

“When a Cordyceps fungus attacks a host, the mycelium invades and eventually replaces the host tissue,” which sounds incredibly unpleasant.   And apparently, the host/ victim has a slim shot at self-defense once infected, as “entomopathogenic fungi… have many novel strategies to escape or suppress host immune responses.” 

More creepily yet, Cordyceps is known to have the ability to control an insect’s end-of-life wanderings, which it benefits from by increasing the likelihood that its spores are dispersed to new hosts.”  This explains our moth’s forced death-march up the tree trunk to a height optimal for re-infection of other critters.  Such mind-control behavior can be illustrated in infected ants – see the National Geographic video below.

These fungi are so effective, they’re used as a bio-control agent against forest and farm pests: 

Entomopathogenic fungi are the most abundant type of microorganisms that infects insects. […] As the natural pathogens of a variety of insects, entomopathogenic fungi can be environmentally friendly alternatives to chemical insecticides for biological pest control.

Learn more / Sources:

Cordyceps comprise a number of species, and we’re not able to distinguish which might be infecting our Cook Forest moth.  

All Cordyceps are members of the Kingdom of Fungi, as follows:

  • Phylum:  Ascomycota
  • Class: Sordariomycetes
  • Order: Hypocreales
  • Family: Cordycipitaceae
  • Genus: Cordyceps

Etymology: Cordyceps is from the Greek, meaning “club head”

CFC zombie moth - insect infected with Cordyceps fungus
he’s not supposed to be so spiky – that’s the fungus

Stargazing in Cook Forest

guide to stargazing in Cook Forest State Park, PA

Sadly, most Americans can’t see our galaxy due to light pollution, but you can still celebrate the Milky Way beneath the dark skies of Cook Forest State Park – a great site for stargazing.  

The Milky Way, lots of constellations, and several planets are easily visible from open areas in Cook Forest.  You don’t even need a telescope (or astronomy binoculars), just clear skies, a weak moon, and a couple of tips.  Here are some resources for stargazing in and around Cook Forest:

Cook Forest Stargazing Links:

Free & current star chart by SkyMaps.com

Northwestern Pennsylvania Astronomy Resources:

Happy stargazing!

But, before you go, here’s an excellent illustration of the difference darkness makes when stargazing – or, when practicing celestial navigation:  

Light pollution threatens wildlife health, disrupts circadian rhythms, derails pollination, and greatly reduces the quality of stargazing.  Find out how you can help combat it, and keep our skies dark: 

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

Green Elfcup Fungus

Green Elfcup Fungus

Tiny Turquoise Mushrooms!

Identified for the CFC by instagram photographer @fungiwoman, Chlorociboria aeruginascens, a/k/a green elfcup, is the fungus behind that gorgeous turquoise wood you’ll find on Pennsylvania trails.

While the stained wood is common, spotting the tiny, 2-5 mm diameter fruitbodies is a rarity.  They occur in summer and fall in the Northeast – these were found on 2 Sept 2020, on Cook Trail in Cook Forest State Park, Pennsylvania.  Green elfcup prefers hardwoods, particularly oak, and little shards of the fallen wood that has hosted it can be found on trails and amongst the fairy moss, which seems fitting.

Etymology: aeruginascens is Latin meaning “becoming blue-green”

Learn more:

  • https://www.mushroomexpert.com/chlorociboria_aeruginascens.html
  • https://www.first-nature.com/fungi/chlorociboria-aeruginascens.php
Green-stained wood
the result of the little fungi: green-stained wood, or blue-stained wood, which we call turquoise wood...

Chlorociboria aeruginascens

Phylum: Ascomycota
Order: Helotiales
Family: Helotiaceae

“Fourteenth and 15th century Renaissance Italian craftsmen used the wood to provide the green colors in their intricate inlaid intarsia designs” – to see some examples, and read some heavy-duty science, visit this link to a botany page of the University of Wisconsin-Madison.

Shagbark Jones before he fled
Shagbark Jones found the fungus, then disappeared into the forest at a wild gallop. He is in big trouble.

Acorns: Science & Mysteries

Penn State Forest Stewards series article – written by Jim Finley, Professor Emeritus, Forest Resources Management, Center for Private Forests at Penn State.

Oaks are economically important tree species in Pennsylvania and across the East. Acorns, or mast – a word derived from old English which means “forest food,” are important to wildlife. Oak-borne mast production varies from year to year. Much research has sought to predict masting years, when big acorn crops occur, and shed light on what leads to poor years – or early acorn abscission (detachment) – like you may have seen this season.

Science and Mysteries of Acorns - Pennsylvania Forest Stewards article

Oaks separate into two groups, popularly referred to as red and white, and learning to identify the difference between the two groups is easy.

Red oaks – e.g. Northern red oak, pin oak, scarlet oak, and black oak – have small “bristles” on the lobes and tips of their leaves. White oaks – e.g. white oak and rock, or chestnut, oak – lack these bristles, and have rounded leaf lobes.  (CFC note: the image above is of a white oak.)  There are other differences that are more difficult to recognize, such as acorn structure and wood anatomy.

The Process of Creating an Acorn –
and the Trials of 2020

Both red and white oaks produce female and male flowers on the same tree, unlike ash which has male and female trees. The process of producing an acorn starts late in the growing year when the male flowers form as the tree’s growth slows toward the end of summer. That is the end of the first year (year 1) in the process. Then, in the second year (year 2), as the tree comes out of dormancy, female flowers form in the axil of the leaf stem and the twig and remain dormant. As the spring leaves begin to unfold, the male flowers emerge and are very apparent as rather-long, drooping, greenish-yellow catkins. These appear about two weeks before the much smaller female flowers emerge.

White Oak Acorn Production

For the white oaks, as the male and female flowers emerge in year 2 as described above, pollination and fertilization should happen. The pollen from the male flower, which is wind-disseminated, lands on the style, which is part of the female flower. When this happens, the pollen initiates the development of a pollen tube that transfers male cells into the ovule to complete fertilization and the process of acorn formation should start in earnest. For this to happen, it is ideal to have warm days and cool nights. 

If temperatures are not right, fertilization may fail, and the female flowers will abort, which results in low acorn initiation. Alternatively, if temperatures become too hot or drought conditions occur, white oak acorns may abort, which is likely apparent in mid-June to mid- to late-July; perhaps that is the reason for reported early acorn drop this year. The other big threat to white oak acorns is late spring frosts, which also happened this year, and would again remove the fertilized flowers.

HWA in Cook Forest – 2020 Update

Hemlock Woolly Adelgid – it’s a non-native invasive insect that’s a massive threat to the old-growth hemlock trees of Cook Forest, and it’s still here.

Hemlock Woolly Adelgid in Cook Forest State Park - present in 2020

Hemlock Woolly Adelgid in Cook Forest State Park

Hemlock woolly adelgid (HWA) has been consistently treated by state agencies since it was first found in Cook Forest State Park in 2013.  First – the bad news – it’s still here.  The photo above was taken in May 2020, and those white little cotton-like tufts confirm the presence of HWA on hemlock trees within park boundaries. 

The good news: 

  • the infestation is not blanket, but concentrated in small areas; 
  • the Eastern Hemlocks in Cook Forest remain largely healthy;
  • the state is continuing treatment, even in this most uncertain of years — 100,000 inches of trees are scheduled to be treated again in 2020, as soon as rainfall rises the water to levels enabling soil injection

HWA was never going to be a short-lived threat, and it’s important to keep in mind the utter devastation it wrought in the Great Smoky Mountains, where it hit first, and in a warmer climate.  The PA Bureau of Forestry continues to work toward establishing a bio-control for the insect, as exists in places where HWA is native (the Pacific Northwest and Japan).  Until then, regular treatments can keep these hemlocks healthy, and their surrounding ecosystems intact.  Eastern Hemlock is a “keystone” species, and integral for keeping our streams cool and clear, for filtering pollutants, and for and managing storm runoff. 

These tasks become more challenging as our climate cycle changes – we’ve experienced stronger, shorter storms punctuating long dry periods, which means less water is being absorbed into the aquifer.  Western Pennsylvania also had a warm winter, which favors reproduction of HWA – and they reproduce exponentially.

HWA – What can be done by individuals to protect Hemlock trees?

Monitoring is of utmost importance – regularly check the health of the hemlocks in your yard, and stay vigilant when hiking or out on state forest lands.  Since HWA often infects trees from the top down, especially check branches blown off by wind, and the upper canopies of hemlock trees that have recently fallen.

We appreciate your supporting ongoing efforts – both in the state and private sectors – to control HWA.

  • Private landowners seeking assistance for trees they think may be infested can contact the CFC, or their county’s Service Forester.
  • To report infestations found on public land, please email PaForester@pa.gov – it’s ideal if you can provide a GPS location, and a clear photograph of the suspected bugs, as well.

Follow these links to learn more about the importance of eastern hemlock, or the invasive insect threatening it – hemlock woolly adelgid.

Trees and Dry Conditions

Penn State Forest Stewards series article – written by Allyson Muth, Interim Director, Center for Private Forests at Penn State.

Many areas across the northeastern US are experiencing dry and drought conditions, Pennsylvania included. As of July 28, two-thirds of Pennsylvania was in an abnormally dry to moderate drought condition. Yet, tallied across the state, we are very close to the total predicted rainfall for an average year to date. Depending on where you look in Pennsylvania, the regions are somewhere between 25% below, to as much as 26% above annual precipitation. These numbers don’t sound like they would result in two-thirds of the state be in abnormally dry conditions. So, how does that work?

PAFS article tree health during drought

Climate Change

Climate change models for Pennsylvania have consistently predicted the pattern that we’re seeing this summer. Less frequent, but more intense rainstorms, with extended drought periods occurring between those large rain events. The result is highly variable and uneven conditions across the state. Conversations with landowners in the south central region have shared their recent 4-inch rain storm events and subsequent flooding. In many other Pennsylvania regions, rains came early, and we’ve entered a dry summer period with rather infrequent rain events.

Pennsylvania is known for its waterways – over 86,000 miles of streams, creeks, and rivers. We usually have ample water during the growing season. We rarely have the water conservation requirements that the US West and Midwest implement to conserve water for human consumption. But when it’s this dry, do we need to worry about the trees?

Contributing Factors

Healthy, established trees can normally withstand relatively long periods of drought, so long as there are intervening months or years that are more favorable. However, recently planted trees, or trees with small soil footprints (rootprints?) are more susceptible to decline under these dry conditions.