Until quite recently I thought earthworms were native. All my life I’ve watched robins yank them out of the soil and seen them on the sidewalk after heavy rain. Gardeners and composters are happy with them, too, but…
What’s good for the garden is lousy for North America’s forests. Earthworms churn the soil column and devour leaf litter, invertebrates and fungi that our northern forests rely on. The result is a lack of ground cover and poor regeneration of the trees.
Like the emerald ash borer, we humans have accidentally introduced a species that’s bad for the forest. The only way to stop it is for us to stop moving worms and soil. Composters and gardeners take note! If you’re on the edge of the earthworm advance — in Minnesota or Maine, for instance — don’t buy worms. (Pittsburgh isn’t on that edge; earthworms have been here a very long time.)
Honey locust seed pod (photo by Andrew Dunn from Wikimedia Commons)
These fruits are food for giants that are now extinct.
Just 13,000 years ago the Americas were inhabited by mammoths, horses and giant ground sloths whose diet included “monkey balls,” avocados and honey locust pods. Only a giant could eat such large fruit in one gulp and pass the seeds through its digestive track.
The giant ground sloth (Megatherium) for instance weighed 4 tons (8,000 pounds) and could reach 20 feet up when he put his paw on a tree trunk and stood on his hind legs. He could also damage the trees so the honey locust evolved big thorns for protection.
Megatherium, extinct ground sloth (illustration from Wikimedia Commons)
He’s been extinct for 10,000 years, but the tree remembers.
For a fun 5-minute video about the fruits that point to missing mammals, watch below.
(photos from Wikimedia Commons. Click on each image to see its original)
Notes and links:
Horses were extinct in North America until the Spaniards imported them. Modern horses eat monkey balls.
Here’s the story of a great idea that went sour really fast because people didn’t observe bird behavior.
During the 1800’s many Britons emigrated to New Zealand and began farming. As the settlers cleared the forest, New Zealand’s native birds (which are flightless) retreated or became extinct.
Soon insect pests proliferated and the farmers clamored for a solution. Someone had a bright idea, “I know! Birds eat bugs. Let’s import a bird.”
The Acclimatisation Societies decided to import the yellowhammer (Emberiza citrinella), a sparrow-like Eurasian bird famous for his pretty song. They lined up dealers in Britain who captured local yellowhammers and shipped them overseas. New Zealand’s farmers welcomed them with open arms.
It didn’t take long to find out this was a terrible mistake. The birds ate the crops, not the insects.
Look at his conical bill and you can tell the yellowhammer eats seeds all year long. In fact, he only supplements his diet with insects during the breeding season.
Soon New Zealanders hated the yellowhammers. In 1880, only 15 years after the first birds arrived, the last shipment was turned away and sent to Australia. Farmers hunted, poisoned and raided yellowhammer nests, trying to rid the country of this once welcomed bird but it was too late. Yellowhammers were firmly established in New Zealand and are widespread today.
They’d have saved a lot of trouble if someone had paid attention to what yellowhammers eat.
Lyme Disease incidence in U.S. 2014 (map from CDC.gov)
In case you missed it on the radio …
Oh no! That dark blue spot on the map is bad news. Each microscopic dot represents an incident of Lyme disease in 2014. Look at western Pennsylvania!
This year Lyme disease came closer to home than ever before. Several friends of mine caught it this summer in Allegheny County, in suburban Pittsburgh.
Do these anecdotes represent a real increase in local Lyme disease? If yes, what is causing it? And does it have anything to do with our weather or climate change?
I posted my question on the iSeeChange website (here) and The Allegheny Front‘s Kara Holsopple investigated. She found out that Lyme disease is increasing in western Pennsylvania and there’s more than one reason for it. Warmer winters (climate change) do play a part.
Acid mine drainage in well water (photo by Kate St. John)
Two weeks in Maine where the water is clean re-opened my eyes to something I take for granted in Pennsylvania: some places have orange water.
Perhaps you’ve been to this restroom at the Route 528 boat launch in Moraine State Park. The restroom is clean but the water is not. “Notice. Non-potable water. Not for Drinking.” The metallic smell and orange-stained sinks and toilets make you wonder, “If the water’s that bad, should I use it to wash my hands?”
Coal mining contaminated the ground water here(*). The orange water is acid mine drainage. When the coal was removed it exposed pyrite which, when exposed to water, turns into sulfuric acid and iron. Bad water from old surface and underground mines flows into streams and wells in Pennsylvania’s coal regions.
The good news is that Pennsylvania stepped in with coal mining laws in the 1960’s that prevent new water contamination and PA Department of Environmental Protection (DEP) can require clean up when an old mine is reopened. Slowly, the worst water is being treated and improved.
That’s how part of the Conemaugh River turned from orange to clear in Somerset County in 2013. See before and after pictures and read about the impressive change here on the Allegheny Front.
Rock with hashmark pattern across it (left to right) at Ferncliff, Ohiopyle (photo by Kate St. John)
Years ago when I first hiked the Ferncliff Trail at Ohiopyle I was puzzled by this pattern on the rock beneath my feet.
In those days there weren’t interpretive signs nearby so I tried to make sense of it as best I could. I decided it was a motorcycle track, but I couldn’t figure out how the vehicle had gotten there and why it had run from the cliff into the river.
Duh! Motorcycles don’t leave tracks in rock. It’s a fossil.
Fossil at Ferncliff Peninsula (photo by Kate St. John)
Though I’ve seen the other ones this is the fossil I like the best.
Lepidodendron was a tree-like plant with scales on its trunk that grew as high as 100 feet tall.
Drawing of Lepidodendron by Eli Heimans, 1911 (image from Wikimedia Commons)
It lived and died in the Carboniferous (coal making) era. If the tree had fallen in a swamp it would have become peat and then coal, but it happened to fall on sand so the patterns of its scaly trunk were preserved in rock.
Not far away is one of Lepidodendron’s last living relatives: Lycopodium or groundpine. Only 6-12 inches tall, its tiny trunks and branches provide a visual hint of its ancestor’s appearance.
Tree Groundpine, Lycopodium dendroideum (photo from Wikimedia Commons)
The past and present are near each other at Ferncliff Peninsula.
(fossil photos by Kate St. John. Drawing of Lepidodendron and photo of Lycopodium from Wikimedia Commons; click the images see the originals)
What we’ve been calling three species are merely variations in color and size. Other species vary, too. Humans, for instance.
Now that the weight of DNA evidence merges hoary, common and lesser redpolls into one species it’s only a matter of paperwork, review, and voting at the American Ornithologists’ Union to make this official.
I’ll be happy when its done. I’ve seen common redpolls but not hoary ones, and now I won’t have to go out of my way to find a hoary redpoll unless I’d like to see his beautiful pale feathers. This simplifies my winter travel plans considerably.
Read more here about the only redpoll in Cornell Lab’s All About Birds blog.
(photo of a (formerly) hoary redpoll at left and common redpoll at right by dfaulder via Wikimedia Commons. Click on the image to see the original)