Wait, Deer Don’t Get Lyme Disease?

First, I want to say thank you to everyone who registered for the upcoming Old-Growth Forest Ecology Outing on May 31 and June 1. Both programs are sold out. Stay tuned for more Learn Your Land events this year!

I also want to mention that Exploring Wild Ecosystems will be open for enrollment on Monday, May 12. This is my newest online course intentionally designed to improve your practical knowledge of ecology. If you’re looking to develop ecological literacy and become a better naturalist, consider enrolling on Monday, May 12.

And now on to the newest video…

If you’ve spent enough time in tick-prone areas, you’ve probably seen ticks sucking the blood of deer. Logically, it makes sense that deer would at least be carriers of the Lyme disease spirochete. After all, white-footed mice and other mammalian tick hosts can be reservoirs for the bacteria.

But white-tailed deer are different. Their blood isn’t like the blood of other animals.

Scientists have been studying the relationship between deer and Lyme disease for decades. The newest research is quite fascinating, and in a brand-new video, I address some of the misconceptions surrounding the role of deer in transmitting Lyme bacteria.

Do deer ever get Lyme disease? If they don’t, what is it about deer that makes them immune? If deer are immune, why do ecologists still advocate for a reduction in the deer herd as a way to reduce Lyme disease rates in humans?

You can watch the brand-new video here.

Thanks for reading and watching, and thanks for your continued support!

— Adam Haritan

Old-Growth Forest Ecology Outing — New Event Scheduled!

I’m really excited to announce that I’ll be leading an Old-Growth Forest Ecology Outing in a few weeks, and I’d love for you to join me.

This outing offers a unique in-person opportunity to learn the rich ecology and distinctive features of older forests.

We’ll begin the day by walking through a mature upland hardwood forest and discussing forest ecology. In the afternoon, we will explore a magnificent old-growth conifer forest and discuss old-growth forest dynamics.

In addition to learning key characteristics of mature and old-growth forests, participants will learn tree identification techniques; mushroom ecology and identification; the influence of geology on forest development; ways to interpret forest history; the role of fire as an ecological agent; old-growth forest misconceptions; and much more.

This event will take place in Cook Forest State Park. Located in northwestern Pennsylvania, Cook Forest is home to one of the last remaining old-growth forests in the entire region, currently hosting 11 old-growth areas totaling over 2,300 acres. One of the areas within the park, the Forest Cathedral, contains arguably the finest concentration of old-growth trees in the northeastern United States. This remarkable area is home to dozens of old-growth eastern white pine and hemlock trees, many over 300 years old and towering above 140 feet in height.

This outing is the perfect opportunity to learn, explore, and connect with nature in a truly spectacular setting.

Interested? Here are the details:

When: Saturday May 31, 2025 or Sunday June 1, 2025 (Choose one date; both programs will cover the same material.)
Where: Cook Forest State Park, Pennsylvania
Time: 10:00 am — 4:00 pm

To maximize your learning experience, space is limited and registration with payment in advance is required to secure your spot.

To learn more and to register, click here and choose the appropriate session.

I’d love to see you there!

—Adam Haritan

Egg-cellent Dyes

Egg-cellent Dyes

California’s Dangerous Path: Oil Refinery Takeover & The Coming Supply Crisis

California’s Dangerous Path: Oil Refinery Takeovers and the Coming Supply Crisis

A Massive Maple Lives In These Woods

Rough, weathered, worn, and warped.

Humans try to avoid these four conditions. Old trees embrace them.

This is why I advocate taking long walks in the woods. In wooded ecosystems, we sometimes discover the ragged splendor of old trees.

On a recent walk in a hardwood forest, I rediscovered a tree I had first encountered many months ago. Rough, weathered, worn, and warped, it’s one of the most remarkable trees I have ever seen.

To learn more about this aged beauty, check out the brand-new video.

Thanks for reading and watching! Have you seen any remarkable trees lately?

— Adam Haritan

An Easy Way to Identify Certain trees in Winter

Want to improve your winter tree identification skills? Here’s a good tip: Look for marcescent leaves.

Marcescence describes leaves that have turned brown and are still attached to trees. These withered leaves often persist on the trees until spring.

As you might expect, marcescence isn’t a feature displayed by too many woody plants. When you see a marcescent tree or shrub, you can narrow down your ID choices to a relatively small number of species.

In the temperate woodlands of eastern North America, marcescence is often displayed by hornbeam (Carpinus), beech (Fagus), witch-hazel (Hamamelis), hophornbeam (Ostrya), and oak (Quercus).

No one is exactly sure why marcescence exists. Here are a few hypotheses:

It allows plants to photosynthesize longer into the autumn season.
It deters herbivores from browsing twigs and buds.
Marcescent trees provide shelter to animals that in turn provide nutrients to trees.
Marcescent leaves, when they finally fall off, provide pulses of nutrients to their host trees.
Marcescent leaves, when they finally fall off, smother new growth of competing woody plants in the spring.

All of these statements can be true to some degree, but it is uncertain whether any one of them is the true reason for marcescence.

Still, you and I can use marcescence to our advantage when attempting to identify woody plants. A good first step is to learn which woody plants are marcescent in our region. We can then seek out these plants, spend some time with them, and fall in love with the process.

To learn even more tips for identifying trees, consider enrolling in Trees In All Seasons. Today is the final day of the winter sale.

You can learn more and register here.

Also, if you’re interested in learning how to forage mushrooms this winter, consider enrolling in Foraging Wild Mushrooms. This 4-season online course is on sale until the end of today, December 23.

Thanks for supporting nature education!

— Adam Haritan

Questions To Ask A Tree

“The wonder is that we can see these trees and not wonder more.”

It’s no surprise that Ralph Waldo Emerson wrote these words. The famous American writer was intimately connected to trees: He planted trees, gathered their fruits, and taught his children the value of learning their names.

Emerson spoke the language of trees, yet was still humble enough to acknowledge that every encounter with trees presented a fresh opportunity to engage in wonder.

Who are you? How old are you? Why are you here? Can you say anything about the underlying rocks? What can you tell us about the broader ecosystem?

In the spirit of Ralph Waldo Emerson, you and I can ask these kinds of questions every time we encounter a tree. When we ask questions, we engage in wonder.

A basic step we can then take to answer those questions is first to learn the names of trees. Fortunately, there are many ways to learn. We can:

Study tree ID field guides
Learn how to use dichotomous keys
Learn all major physical features of trees (buds, bark, leaves, flowers, etc.)
Learn habitat characteristics of trees
Attend tree ID walks
Visit arboretums (where trees are often labeled)
Cultivate friendships with local tree enthusiasts
Teach others what we have learned

If you’re looking for a carefully curated opportunity to improve your tree identification skills, consider enrolling in Trees In All Seasons. This online course teaches you how to identify 100 trees in every season. It’s currently on sale through Monday, December 23.

You can register and learn more about the course here.

Regardless of how you decide to learn, I strongly encourage you to hone your tree identification skills over time. With learning comes wonder, appreciation, love, and the unraveling of at least some of nature’s mysteries.

—Adam Haritan

Welcoming the Winter Solstice: A Celebration of Light, Magic, and Nature’s Gifts

Welcoming the Winter Solstice: A Celebration of Light, Magic, and Nature’s Gifts

More Earthworms = Less Lyme Disease?

Cases of tick-borne diseases are on the rise, and people are wondering what to do.

Spray more repellent on clothes? Wrap more duct tape around socks? Ingest more Japanese knotweed? Cull more deer?

How about introducing more earthworms into tick-prone landscapes?

It sounds bizarre, but some ecologists are researching this latter strategy. According to a few studies, the prevalence of earthworms is associated with fewer ticks in certain ecosystems.

How is this possible? Why are earthworms associated with fewer ticks? Could the intentional release of earthworms into wild landscapes work as a viable tick-reduction strategy?

In a brand-new video, I address these fascinating questions.

You can watch the video here.

Thanks for reading and watching! Do you have any unique tick-reduction strategies?

— Adam Haritan

The tree that built America

“Why do you like trees so much?”

People routinely ask me this question.

It isn’t an easy question to answer, but I try my best to explain what it is about trees that makes me feel good.

I love the food trees offer. I enjoy the medicine trees provide. I like the shade trees cast. And I admire their beauty.

But there’s something else about trees I really appreciate: their ability to tell stories.

As it turns out, trees tell remarkable stories of peace, tragedy, death, and — believe it or not — democracy.

One notable tale that trees tell quite well is the story of America’s birth as a nation. While many people associate this story with icons like the Liberty Bell and the Declaration of Independence, the founding of the United States is also strongly connected — both physically and symbolically — to one particular tree.

Tall, majestic, and extremely useful, this tree has been famously labeled “the tree that built America.”

To learn more about this celebrated tree, check out the brand-new video.

Speaking of trees, I was recently interviewed on Harvesting Nature’s Wild Fish and Game Podcast. In the interview, we discussed how trees can help you become a better hunter and observer of wildlife.

You can listen to the interview here.

Thanks for reading and watching! Do you have any unique reasons for loving trees?

— Adam Haritan