Given the award-winning economist Malcolm Gladwell’s 10,000-hour rule, I became a hiking expert at the ripe old age of four. It helps that I grew up in Montana where many kids — myself included — take their first steps on trails. Baby hiking boots are a thing, and trust me: they’re ridiculously cute. But just because I’m statistically proficient at hiking, doesn’t mean I don’t have a million mistakes under my belt. After all, the only difference between an expert and a beginner is that an expert has already made their fair share of blunders.

Fall is a tricky time to hike. The weather is changing, and transitional seasons require more technical gear. Plus, you have to pack more layers than you’d need for an August outing. That means you’ll need a bigger backpack. But don’t do what I did a few weeks ago when I went hiking in Graubunden, Switzerland and bring a bag so big the locals — who are world famous for being polite — give you serious side-eye. Whether you’re worried about wearing the wrong footwear or fabric, below are 16 examples of what not to wear for fall hiking. Most importantly, I’ve included what to put on or pack instead. 

Don’t wear: 100-percent leather boots

Wear this instead: Synthetic hiking boots 

Don’t get me wrong: 100-percent leather boots last a long time, and they look cool. But they require a longer break-in period, and I don’t love them for fall hiking because they’re not waterproof. I live in Montana where we had a winter weather advisory last week. (Yes, fall hiking here usually involves snow and wet conditions.)

Fortunately, Merrell makes the Moab 3 Mid, a soft, but sturdy synthetic boot with a waterproof membrane that keeps moisture out. In the last 15 years I’ve owned three pairs of these boots which have an impressive 4.7-star average rating on Amazon. This fall, I’m treating my feet to their fourth pair, the new Moab 3 Vista Mid. “Great hiking boots with no break-in period,” wrote one hiker who wore them on two 10-mile days in Yellowstone and Grand Teton National Parks. 

Don’t wear: Everyday leggings

Wear this instead: Technical leggings

While everyday leggings aren’t the worst bottoms to wear hiking (that award goes to skinny jeans or leather pants), they’re up there. After working at Lululemon and learning all about different fabrics and fits designed for movement and the elements, I now only wear technical leggings on the trails.

These Toad & Co tights cost more than a $20 pair of leggings you’d wear to the grocery store, but they’re far more breathable, moisture-wicking, and quick-drying. While they are already fairly stretchy, they also feature stretch-woven patches at the knee and seat for freedom of movement while trekking and scrambling. Plus, they have pockets at the thighs and back to store your smaller essentials or items you want to keep closer at hand.

Don’t wear: One-season jacket

Wear this instead: Transitional jacket 

Because fall is a shoulder season, it can feel like July one day and January the next. When I’m outside during these temperamental months, I prefer transitional pieces that work for a range of conditions. My ultralight 3.4-ounce packable Patagonia Houdini summer rain jacket goes into storage, and out comes my Columbia Switchback Rain Jacket. It has a longer length and is fully-lined, so I stay warm even when there’s frost on the ground. That said, it’s made of nylon and polyester, so it’s still pretty lightweight.

Don’t wear: Road shoes 

Wear this instead: Trail running shoes 

My friend Kayla Regulski is an avid runner who runs sub-3 marathons. Still, she was in pretty poor shape when I took her on a 5-mile hike in South Africa. She’d only packed her road shoes which had no tread and left her in some pretty precious situations when the trail was rocky or slick. Meanwhile, I did just fine in my beloved Altra Olympus 5 Trail Running Shoes. They have grippy Vibram outsoles, so I feel confident on uneven or wet terrain.

I’ve owned two pairs of Olympus 5, and I’m looking forward to trying Altra’s newest offering, the waterproof and windproof Timp 5 GTX Trail Running Shoes, this fall. The brand is billing it as “the ultimate shoe for the upcoming shoulder season.” Not a fan of Altra’s wider toe box? Check out the new Merrell x Janji Agility Peak 5 Trail Running Shoe. It has a more neutral width and fun features like an odor control treatment and gaiter loops (gaiters are a must for fall hiking where there’s snow).

Don’t wear: Cotton base layers

Wear this instead: Merino wool base layers

While cotton is the fabric of choice for some astronauts in space, it’s the worst fabric to wear in the fall, especially outdoors. But don’t just take it from me. According to the American Hiking Society, “cotton is not suitable for hiking” because it “readily absorbs and retains water leaving the hiker wet, which is a dangerous situation.”

Merino wool, on the other hand, is naturally moisture-wicking. And because it serves as insulation for sheep, it’s also thermoregulating making it the ideal material for changing temperatures. My go-to top for fall hiking is my Fjallraven Abisko Long Sleeve Merino Shirt. It has anti-stink properties, so it can go days between washings, and unlike scratchy wool, it’s so soft I use it to clean the lenses on my expensive Nike Flyfree Sunglasses. 

Don’t wear: Single Hiking Stick

Wear This Instead: TrailBuddy Trekking Poles

With an impressive 4.7 rating and more than 49,000 five-star ratings at Amazon, these aluminum hiking poles are surprisingly strong, durable, and lightweight, considering their affordable price point. They can be adjusted in seconds, collapse down to easily fit in your backpack, and feature padded straps and moisture-wicking cork handles that feel comfortable in your hands even after miles walking.

Not to mention, they are the safety item you never knew you needed on the trails, since they help prevent you from losing your footing and falling on steep or more challenging hikes, according to hikers. Another happy hiker also recommended these trekking poles over a walking stick: “I’ve had this pair for 10 months now and have hiked well over 300 miles with them. They have saved me from too many falls and potential injuries to count. Won’t hit the trail without them.”

Don’t wear: Bulky fleece

Wear this instead: Lightweight microfleece

My favorite new outer layer is this best-selling Lululemon Scuba Half-Zip Hoodie. But between its oversized fit, large “scuba” hood, and plush, thick, cotton-blend fleece fabric, it’s not the best hoodie for hiking. Instead, opt for a hoodie made with microfleece. It’s just as warm, but because the fibers are thinner, the fabric is lighter. It’s also more breathable, so it dries quicker. Look for hoodies with fleece from Polartec, the pioneer in performance fleece. For example,  consider REI Co-op’s Hyperaxis Fleece Jacket 2.0. It’s made of Polartec’s Power Stretch Pro fleece which offers four-way stretch and is so lightweight (14.2 ounces to be exact) it can be worn as a mid-layer, too. “I basically never took it off,” wrote one satisfied shopper who got this hoodie for a trip to France. 

Don’t wear: Short socks

Wear this instead: Long socks

Most people I know who have trekked to see the mountain gorillas in Rwanda, describe the experience as magical. But the word I use is “miserable.” That’s because I didn’t get the memo that I needed to wear long socks and long pants to keep the fire ants out. In a matter of seconds, an army of soldiers — the size of a grain of rice — ruined my bucket list hike.

Regardless of season or destination, I always hike in long socks now. They keep dirt and sand out of my shoes and protect my ankles from stray branches. Personally, I love these Anlisim Merino Wool Hiking Socks because the padded soles absorb shock, and the merino wool they’re made of has properties that prohibit the growth of odor-causing bacteria. They’re so popular that 3,000 sets (each set has five pairs) were sold last month.  “Warm, quick drying ,and not too bulky,” summed up one Florida-based shopper who wore them on a trip to Iceland. 

Don’t wear: An oversized backpack

Wear this instead: Under-30-liter backpack (unless camping) 

You can always tell a beginner hiker by the size of their backpack. Nine times out of 10, it will be too big for the trail they’re on. I, too, sometimes overestimate how much space I need, and I always regret it. My rule of thumb is 10 liters of space for every three hours of hiking, but REI also has this handy How to Choose a Backpack guide.

For fall day hikes, when you need to pack layers for changing weather, I recommend the Women’s Osprey Tempest 20L. It has a very impressive 4.8-star average rating on Amazon and is adjustable to fit different torso lengths. With a 4.7-star average rating and more than 1,150 five-star ratings, the Men’s Osprey Talon 22L is also a safe bet. 

Don’t wear: Moody colors

Wear this instead: Bright colors  

Vogue editors recently named moody colors as one of their top trends this fall. While I love darker tones, especially black because it pairs with everything, I try to wear bright colors and neons for fall hiking in the U.S. Why? September through December is the most popular time to hunt. I definitely don’t want to be mistaken for a bear or a deer.

With its penchant for eye-catching colors you won’t find in nature, Cotopaxi is my go-to for ultra-visible hiking tops, jackets, and accessories like my new multi-hue Kapai Hip Pack. But, you can also find more affordable “loud” layers from other brands on Amazon. For example, this $30 UPF 50+ Pullover has more than 2,200 five-star ratings and comes in a Fluorescent Green that will make sure you’re seen whether you’re hiking in a forest full of aspens or acacias. 

Don’t wear: Flannel shirts

Wear this instead: Flannel shacket

Forget football. Fall is flannel season. While I spend most of September through December in my favorite Outerknown Flannel Blanket Shirt, I don’t hike in it. Instead, I prefer to hike in flannel “shackets” which, unlike flannel shirts, feature hand pockets and can be worn as both an under and outer layer. In the last few years I’ve hiked everywhere from Portugal to Peru in my UANEO Flannel Plaid Shacket. It has more than 6,700 five-star ratings on Amazon where shoppers describe it as soft, warm, and stylish. Note: Because it’s on the heavier side, I don’t wear it on long hikes where I’m counting every ounce. I also don’t recommend wearing it if you’re not willing to tell other hikers where you got it. Trust me: you’ll get compliments.

Don’twear: Open-toe sandals

Wear this instead: Close-toed sandals

While I prefer to hike in boots after Labor Day, on uncharacteristically warm fall days, I can sometimes be found sporting sandals. I used to hike in Chaco’s Z Cloud or Teva’s, but after my 200th stubbed toe, I switched to Keen’s. The Oregon-based brand’s signature closed-toe sandals keep all your piggies protected and provide almost as much support and traction as trail running shoes. Yet, your feet still get to breathe. Plus, you can hike sans socks (just don’t do it in Rwanda).

Keen’s popular Whisper sandal has more than 18,000 five-star ratings on Amazon. One shopper who calls them their “magic shoes” and “foot mittens” wore them on a recent trip to Guatemala where they were “perfect” for everything from hiking up a volcano to strolling Antigua’s cobblestone streets. 

Don’t wear: A second jacket

Wear this instead: a packable down vest

If I had to choose between free pumpkin spice lattes for life or a Canada Goose Cypress 750-Fill-Power Down Vest, let’s just say I’d be one cozy and cute, albeit uncaffeinated hiker. Whether you spend $500 or $50 (if you’re on a budget I recommend REI Co-op’s 650-fill vest) on this essential layer, you’ll find it’s a lot easier to hike in than a second jacket. Your arms will be free, so you’ll have a wider range of motion and less bulk. That said, your core—which sends blood to your limbs—will stay warm. I’ve hiked in dozens of countries while wearing this popular Patagonia Down Sweater Vest that packs down into its own pocket. If having an insulated hood is more important than packability, check out Patagonia’s Bivy Hooded Down Vest. 

Don’t wear: Bear bells

Wear this instead: Bear spray

I spent last week hiking in Glacier National Park where years ago I encountered a grizzly bear on a trail at dusk. I was so sure it was going to eat me, I left a voice note on my phone telling my family I loved them. Spoiler alert: I made it out unscathed.

Because bears hibernate in the winter, they’re most active in fall, foraging for food pretty much 24/7. But that shouldn’t keep you from hiking. Just don’t do what some tourists do and rely on bear bells to keep you safe. According to this NPS’ hiking in bear country guide, bear bells “are not adequate or effective.” Instead, wear a can of bear spray on your hip, chest, or anywhere you can access it within 2.5 seconds. Also, check the expiration date. Most bear spray has a shelf life of around 3-4 years.  

Don’t wear: A regular cotton bra

Wear this instead: A bra made for movement

Because hiking is a low-impact sport, I used to think I could get away with wearing a regular cotton bra. But every time I did, I had regrets. They’re just not as comfortable, especially when wet. These days, I only hike in sports bras like this moisture-wicking prAna Chakara bra with UPF protection. On sale, it’s only available in sizes S and XS. For more options, consider this REI Co-op Merino Bralette, available in sizes XS-3X. It’s made of merino wool, so it’s naturally odor-resistant and temperature regulating. And in lieu of an annoying clasp, it has a stretchy band and adjustable straps. 

Don’t wear: A backpack without a hip belt

Wear this instead: Backpack with a hip belt

From Australia to Antarctica, I never travel without this packable backpack with nearly 13,000 five-star ratings. That said, I don’t use it for hiking, especially in the fall. It doesn’t have a hip belt which is a dealbreaker for hikes when I want to pack extra layers or a heavy Stanley thermos filled with hot apple cider to enjoy on the summit. Hip belts are essential for more even weight distribution.

While I’m a big fan of Osprey backpacks, I’m also partial to the NEMO Resolve 35L Endless Promise Technical Active Pack because its hip belt has pockets where I can stash my lip balm, allergy pills, and other small essentials I don’t want to have to dig around for. It’s also made of a tear-resistant recycled polyester that’s two to three times stronger than the industry standard and 20 times more water-resistant. 

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