257 entries · page 1 of 11
Field Notes
How to identify the plants, animals, mushrooms, tracks and rocks you find outside, with the look-alikes and safety notes that matter.
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Michael C. Rygel / Wikimedia Commons (CC BY-SA 3.0)FN-0257 · Rocks & Minerals
How to Identify Diorite (and Tell It From Granite)
Diorite is a coarse-grained, salt-and-pepper igneous rock of white plagioclase and black hornblende, with little quartz and no pink feldspar.
Wikimedia Commons / Wikimedia Commons (Public domain)FN-0256 · Plants, Vines & Weeds
How to Identify Chert (and Tell It From Flint)
Chert is a hard, fine-grained quartz rock with a waxy luster and sharp conchoidal fracture that does not fizz in acid, in gray, brown, tan, or black.
Famartin / Wikimedia Commons (CC BY-SA 3.0)FN-0255 · Trees
How to Identify a Juniper (and Tell It From Cedar)
Juniperus virginiana
A juniper has scale-like foliage, prickly juvenile needles and blue berry-like cones, unlike the flat sprays and woody cones of arborvitae or a true cedar.
Siim / Wikimedia Commons (CC BY-SA 3.0)FN-0254 · Rocks & Minerals
How to Identify Gneiss (the Banded Metamorphic Rock)
Identify gneiss by its coarse grain and alternating light and dark bands of quartz, feldspar and mica, and tell it from granite and schist.
David J. Fred (Dfred) / Wikimedia Commons (CC BY 3.0)FN-0253 · Fossils
How to Identify a Petoskey Stone (Michigan Fossil Coral)
Hexagonaria percarinata
A Petoskey stone is a fossil coral you identify by its six-sided cells, each with a dark eye and fine radiating lines, seen best when the stone is wet.
Marton Berntsen, crop by User:MPF / Wikimedia Commons (CC BY-SA 4.0)FN-0250 · Mammals
How to Identify a Weasel (Long-Tailed vs. Short-Tailed)
Mustela erminea
How to identify a weasel by its long slender body, short legs, and black-tipped tail — and tell a long-tailed weasel from a short-tailed ermine.
Fernando Domínguez Cerejido / Wikimedia Commons (CC BY-SA 4.0)FN-0251 · Rocks & Minerals
How to Identify Limestone (and Tell It From Other Rocks)
How to identify limestone by its soft pale stone, its fizz with vinegar, and its marine fossils — and tell it from dolomite, chalk, and sandstone.
Bill Ebbesen / Wikimedia Commons (CC BY 3.0)FN-0252 · Tracks & Signs
How to Identify Shed Antlers (Deer, Elk, and Moose)
How to identify a shed antler and tell whether it fell from a deer, elk, or moose by its size, beam, and tines — plus where and when to find them.
Didier Descouens / Wikimedia Commons (CC BY-SA 4.0)FN-0249 · Rocks & Minerals
How to Identify Citrine (Real vs. Fake)
How to identify real citrine by its even, smoky-yellow color, and spot heat-treated amethyst sold as citrine by its white base and burnt-orange tips.
Mount Rainier National Park from Ashford, WA, United States / Wikimedia Commons (Public domain)FN-0248 · Mammals
How to Identify a Fisher (the “Fisher Cat”)
Pekania pennanti
How to identify a fisher (fisher cat) by its long dark weasel-like body, bushy tail, and low bounding gait — and tell it from minks, martens, and otters.
Paul Hirst (Phirst) / Wikimedia Commons (CC BY-SA 2.5)FN-0247 · Reptiles & Amphibians
Green Anole vs. Brown Anole: How to Tell Them Apart
Anolis carolinensis
Green anole vs. brown anole: green anoles can turn brown but keep a white chin and climb high, while brown anoles stay low with striped, patterned backs.
Rhododendrites / Wikimedia Commons (CC BY-SA 4.0)FN-0245 · Birds
How to Identify a Blue Jay (Field Marks and Calls)
Cyanocitta cristata
How to identify a blue jay by its blue crest, black necklace, white-marked wings and tail, and loud "jay! jay!" calls — and tell it from bluebirds.
Robert M. Lavinsky / Wikimedia Commons (CC BY-SA 3.0)FN-0246 · Rocks & Minerals
How to Identify Opal (Real vs. Fake)
How to identify opal by its shifting play-of-color, waxy luster, and 5.5–6.5 hardness — and tell solid stones from doublets, triplets, and glass fakes.
Yathin S Krishnappa / Wikimedia Commons (CC BY-SA 3.0)FN-0242 · Mammals
Coyote vs. Wolf: How to Tell Them Apart
Canis latrans
Coyote vs. wolf: wolves are far larger with broad snouts and short rounded ears, while coyotes are lean with pointed snouts and a low, bushy tail.
The stone gate / Wikimedia Commons (CC BY-SA 4.0)FN-0244 · Rocks & Minerals
How to Identify Granite (and Tell It From Other Rocks)
How to identify granite by its coarse, interlocking crystals of quartz, feldspar, and mica — and tell it from marble, gabbro, and gneiss.
Charles J. Sharp / Wikimedia Commons (CC BY-SA 4.0)FN-0243 · Tracks & Signs
How to Identify Bear Tracks (Black Bear vs. Grizzly)
Ursus americanus
How to identify bear tracks by their five toes, broad flat pads, and claw marks — and tell a black bear print from a grizzly bear print.
Paxson Woelber / Wikimedia Commons (CC BY-SA 4.0)FN-0240 · Mammals
Moose vs. Elk: How to Tell Them Apart
Alces alces
Moose vs. elk: tell them apart by size, antler shape, and color — moose are near-black giants with flat, paddle-shaped antlers and a bulbous nose.
Tigerhawkvok / Wikimedia Commons (CC BY-SA 3.0)FN-0241 · Reptiles & Amphibians
Turtle vs. Tortoise: How to Tell Them Apart
Gopherus agassizii
Turtle vs. tortoise: tell them apart by habitat, shell, and feet — tortoises live on land with high domed shells and stumpy, elephant-like legs.
Wikimedia Commons / Wikimedia Commons (CC BY-SA 3.0)FN-0239 · Rocks & Minerals
How to Identify Jade (Real vs. Fake)
How to identify real jade by its cool feel, dense weight, waxy glow, and toughness — plus simple tests to tell jadeite and nephrite from fakes.
Robert M. Lavinsky / Wikimedia Commons (CC BY-SA 3.0)FN-0238 · Rocks & Minerals
How to Identify Turquoise (Real vs. Fake)
How to identify real turquoise by its color, matrix, feel, and hardness — plus simple at-home tests to spot dyed howlite and plastic fakes.
USFWS Mountain-Prairie / Wikimedia Commons (Public domain)FN-0237 · Mammals
How to Identify a River Otter (vs. Mink and Muskrat)
Lontra canadensis
How to identify a North American river otter by its size, thick tapered tail, and playful habits — and tell it from a mink, muskrat, or beaver.
Andy Morffew from Itchen Abbas, Hampshire, UK / Wikimedia Commons (CC BY 2.0)FN-0236 · Birds
Bald Eagle vs. Golden Eagle: How to Tell Them Apart
Haliaeetus leucocephalus
Bald eagle vs. golden eagle: tell them apart by head and tail color, leg feathering, bill size, and the brown juveniles that fool everyone.
Charles J. Sharp / Wikimedia Commons (CC BY-SA 4.0)FN-0233 · Mammals
How to Identify a Porcupine (and Its Lookalikes)
Erethizon dorsatum
How to identify a porcupine by its size, quills, and waddling, tree-climbing habits, plus how to tell it from a hedgehog or beaver.
Gonzalo Devia / Wikimedia Commons (CC BY-SA 4.0)FN-0234 · Rocks & Minerals
How to Identify Amethyst (Real vs. Fake)
How to identify real amethyst by its purple color zoning, hardness, and natural flaws, and how to spot dyed glass and fake stones.
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