Don't freak out, but there's a problem with green roofs: They're not necessarily greener than ordinary roofs. Soooooo kind of a major problem. With a little extra effort, though, green roofs can be efficient AND locally sourced -- you just can’t take the easy way out.

Scientific American reports:

[R]ooftop vegetation has to be able to survive the high winds, prolonged UV radiation and unpredictable fluctuations in water availability. To resist these harsh environments, a majority of green roofs are planted with sedum, a non-native species that can survive wind and long periods without rainfall. A roof planted with sedum, however, is no greener, from the standpoint of sustainability, than is ordinary tar or asphalt.

Sedum, it turns out, absorbs sunlight, just like a tar roof would, and isn't particularly good at absorbing water. Planting your green roof with sedum is like hiring employees based on how long they can physically sit in an office chair instead of how good they are at doing the work.

OK, Holland, we get it! You have all the nice things! Organic food, cool little local shops, bikes, green energy. Way to rub it in.

Yes, we still drive cars! Yes, we are jealous! No, we don't have a minimum of $1,079 to spend on a round-trip ticket from New York to Amsterdam sometime in the next six months.

Back in 2012, 561,633 very nice people went out on beaches around the world and picked up the trash that other people had thrown there. They picked up an astounding 10 million pounds. That's the weight of 5,000 cars. It’s heavier than the Capitol dome.

What's even more astounding is that this isn't even the most trash the Ocean Conservancy has collected in the 27 years this challenge has been going. Twice before, volunteers collected more than this amount of trash, measured in weight, and once before, they collected more total items.

The volunteers found a lot of what you might expect: 2,117,931 cigarette butts, 1,140,222 food wrappers/containers, 1,065,171 plastic bottles, and 958,893 caps and lids.

Back in March we told you about a polar bear who had been orphaned in Alaska when its mother was shot by a hunter. We invited (well, ordered) you to watch it play which, even two months later, remains an experience of acute adorableness. Now we have some good news about this polar bear, little Kali: He has found a permanent home. That home will be at the Buffalo Zoo, where he'll share digs with another polar bear named Luna.

Italian architecture firm Act Romegialli designed this building to start as a little garden house, and then be gradually eaten by the garden.

Here's what it started as, an unused garage structure:

But the architects gave it a coat of plants: honeysuckle and mile-a-minute vine to start with, and then common hops and golden tiara as a flourish. Lower down, perennials (red valerian, Lindheimer's beeblossom, geraniums, and brown-eyed susans) sit by annuals (Mexican asters, marigolds, nasturtium, and red spider zinnias). In the end, you get this:

This is how powerfully good the fast food industry is at making people crave their food: A delivery service in Gaza will smuggle KFC across the Egyptian-Gaza border in order to satisfy cravings for fried chicken. So far, the delivery service, Yamama, has brought in 100 meals, according to The New York Times. Yamama waits for about 30 orders to pile up. And then, this four-hour process begins, which involves multiple cars, smuggling tunnels, and motorcycles:

[A]n Egyptian taxi driver picked up the food. On the other side of the border, meanwhile, Ramzi al-Nabih, a Palestinian cabdriver, arrived at the Hamas checkpoint in Rafah, where the guards recognized him as “the Kentucky guy.”

From the checkpoint, Mr. Nabih, 26, called his Egyptian counterpart and told him which of the scores of tunnels the Hamas official had cleared for the food delivery.

We knew we'd been doing some damage to the planet, but we didn't realize we'd been making it bleed.

They’re up.

I repeat: They are up. My fragile seeds have sprouted into tiny proto-herbs. Miniature leaves unfold by the hour; little stems reach toward the sun. It’s alive, I tell you! I have created life!

Forgive me for going a bit mad with power -- I’m just so excited that my very first foray into growing from seed is actually working so far. Sure, I’ve managed to keep a series of windowsill plants alive in pots over the past few years (bless you, you affable succulents). But I bought all of them as hearty young plants, already strong and bushy and requiring little more than water from me. It’s like adopting a high-achieving college kid -- with all the hard work already done, you can’t exactly call yourself parent of the year.

But my recent seed-bombing expedition awakened something in me. I haven’t yet seen any sprouts from the secret seed bomb I snuck into a corner of my backyard -- my cue to check on the seed-filled clay capsules I lobbed into vacant lots (maybe the dry spell of the past few weeks is to blame?). So while I’m waiting for my guerrilla gardening luck to kick in, I decided to try growing herbs from seed for the first time.

Salt’s membership in junk food’s holy trinity (along with sugar and fat) means it’s one of the food industry’s essential tools for making its products addictively good. (Journalist Michael Moss reveals this in his eye-opening book Salt Sugar Fat, but if you’ve ever housed a box of Cheez-Its solo, you already knew that.) For decades now, limiting salt intake has been part of the public-health mantra; groups like the American Heart Association vilify salt for its links to high blood pressure and cardiovascular disease and recommend that we all aim for no more than 1,500 milligrams a day of salt consumption.

But all of a sudden a new report is causing a stir by saying that recommendation may be meaningless, and that consuming extremely low levels of sodium could actually be harmful.

Far out. Pass the Cheez-Its!

Sadly, it’s not quite that simple. The report, commissioned by the Institute of Medicine and the Centers for Disease Control and Prevention, confuses more than it clarifies. It looks at studies on sodium intake and health outcomes conducted since 2005 — the last time the U.S. issued dietary guidelines on salt. Back then, the USDA recommended that the general population consume 1,500 to 2,300 milligrams a day, and that populations at risk for heart disease and high blood pressure limit intake to 1,500 milligrams. The more recent evidence calls those guidelines into question. The New York Times reports:

“As you go below the 2,300 mark, there is an absence of data in terms of benefit and there begin to be suggestions in subgroup populations about potential harms,” said Dr. Brian L. Strom, chairman of the committee and a professor of public health at the University of Pennsylvania. He explained that the possible harms included increased rates of heart attacks and an increased risk of death. …

There are physiological consequences of consuming little sodium, said Dr. Michael H. Alderman, a dietary sodium expert at Albert Einstein College of Medicine who was not a member of the committee. As sodium levels plunge, triglyceride levels increase, insulin resistance increases, and the activity of the sympathetic nervous system increases. Each of these factors can increase the risk of heart disease.

“Those are all bad things,” Dr. Alderman said. “A health effect can’t be predicted by looking at one physiological consequence. There has to be a net effect.”

Medical and public health experts responded to the new assessment of the evidence with elation or concern, depending on where they stand in the salt debates.

Some experts worry the report will send the wrong message -- that we’re off the hook in terms of watching our salt. A spokesperson for the AHA said the group “remained concerned about the large amount of sodium in processed foods, which makes it almost impossible for most Americans to cut back.”

Various species of whale are showing all sorts of places they shouldn't be, like the Mediterranean, Cape Cod, and now, Namibia. Yesterday, scientists reported that they saw a gray whale off the African coast, which is really, really astonishing. As the Guardian explains:

Not only has this north Pacific species been extinct in the Atlantic since the 18th century, it has never been seen south of the equator.

This is the second gray whale that's been seen wandering in strange waters in the past few years. Another showed up in the Mediterranean in 2010.