Thursday, September 30, 2010

Trip Report: Nuts!

We led a somewhat unusual walk this weekend in that it was mostly on the edge of sports fields. It's amazing what you can find just in the little patches of wild space right in the middle of things.

Our main focus was nuts: the Chinese chestnuts and black walnuts are dropping. Both present real barriers to easy eating: chestnut hulls are covered in prickles, and black walnuts have one of the hardest shells of any nut. But we did our best to get at the tasty snacks inside!

black walnuts
Black walnuts (Juglans nigra)

walk 09210 021
The shells of black walnut are incredibly hard,
but you can get them open with a hammer.

Chinese chestnut(Castanea mollissima)

Beware the prickly chestnut husks! We kicked them with our feet until they opened up to the point we could remove the nuts.

Preview of coming attractions: before we even left the parking lot, we saw persimmons starting to ripen up. It will be several more weeks before they're plentiful, but a few early fruits are already starting to drop. Just make sure you get the really ripe, soft, falling off the tree fruits, or they'll make your mouth pucker something awful.

ripening persimmons
American persimmon (Diospyros virginiana)
Also spotted on the trail:
  • Acorns (Quercus sp.) are also dropping, though they weren't plentiful in our particular spot.
  • There are also wild grapes (Vitis riparia?) growing right over Rock Creek, but they weren't plentiful either.
  • Black haw viburnums (Viburnum prunifolium) have set their fruit, but they're green now; they'll be black (and edible) when they're fully ripe.
What have you been seeing on the trail? Leave a comment and let us know!

Next walk: Autumn olives and other fall edibles on October 9 at Lake Artemesia. Register here.

Tuesday, September 28, 2010

The Potomac Watershed Trash Summit

More than 300 people gathered last Wednesday for the Alice Ferguson Foundation’s (AFF) 5th Annual Potomac Watershed Trash Summit.

Plastic bottles and garbage on the bank of a river
Photo credit: Horia Varlan
A Trash Summit?

AFF's annual Potomac River Watershed Cleanup has pulled 3 million tons of trash out of the Potomac, the Anacostia, and their tributaries since it started in 1989 (including 250 tons in 2010's cleanup). In 2005, after 16 years of running cleanups, the trash-removers decided they needed to get to the root of the problem and inspire people to stop the flow of trash into the river in the first place. They started the Trash Free Potomac Watershed Initiative, with the goal of creating a trash-free Potomac by 2013: "so our 25th cleanup will be our last cleanup."

The campaign includes bringing local jurisdictions together once a year to talk about legislation, law enforcement, and public education. And they've gotten the federal government involved, too. This year, the EPA announced a "trash pollution diet" for the Anacostia River by establishing a Total Maximum Daily Load for trash.  It's a concept usually used for bacteria, PCBs, and other invisible waterborne pollutants. Now we'll also have a limit on more visible pollution.

How did we get to the point that we need this? Many people don't realize that the trash they throw on the ground in the middle of the city eventually washes down storm sewers and into our local rivers. Some long-overdue efforts to change the way the sewer system overflows should eventually help by catching trash instead of floating it into the river. In the meantime, AFF and local partners are teaming up on a public education campaign.

Here are their recommendations for things you can do to help reduce the flow of trash (sign their pledge here):
  • dispose of trash in a responsible manner;
  • pick up at least one piece of litter each day;
  • purchase products made of recycled materials and with less packaging;
  • recycle at home, office, faith-based gatherings, school, and any public event;
  • use reusable shopping bags;
  • limit your use of single-use beverage containers; and
  • spread the word to your workplace, friends, and neighbors.
And save the date for their next Potomac River Cleanup: April 9, 2011.

What else are you doing to reduce trash? What else needs to be done in our region? Leave a comment below.

oil and water
Photo credit: kryn13

Sunday, September 26, 2010

Calendar: Opening and Seeking

I want to remind everyone that we're part of the Takoma Green Homes tour on Saturday, October 2. We'll be hanging out all day, so please stop by and say hello!

Playing games - hide and seek
Photo credit: Andrew Pescod
Also on Saturday, the National Wildlife Federation is hosting an event called Hike and Seek at Seneca Creek State Park. There will be 5 "stop-and-study" stations along a 1.5 mile trail, where kids can earn different badges.

Maybe next year we'll give out badges at our open house...

In the meantime, there's plenty more on our calendar.

Thursday, September 23, 2010

LOOK FOR: Goldenrod (It's Not Causing Your Hay Fever)

I grew up thinking goldenrod caused my fall allergies. They're flowering, I'm sneezing. Case closed, right?

Goldenrod (Solidago canadensis)
Solidago canadensis by 'Metrix X'

In fact, it's a classic case of being in the wrong place at the wrong time. If you read last week's post, you know the main culprit in hay fever: ragweed. Goldenrods just have the misfortune to be much more showy right now, while subtle old ragweed is churning out its pollen grains of misery.

Don't believe it? If you stand by a goldenrod plant for any length of time, you'll see: these flowers are pollinated by insects, not wind. Their pollen is only headed up your nose if you stick it right in there with the bees. (If you do that, goldenrod still might make you sneeze. But at that point, it's your fault.)

There are hundreds of species of goldenrod, and dozens in the Mid-Atlantic. All have tiny yellow flowers that look like miniature daisies on close inspection. The flowers are often in long "wands," but sometimes in small clusters or on branches.

Grey Goldenrod
Grey goldenrod (Solidago nemoralis) by 'milesizz'
Blue-stemmed Goldenrod
Blue-stemmed goldenrod (Solidago caesia) by 'milesizz'

There are several species of insects that are closely associated with goldenrods; they've either adapted coloring that works well with the flowers, or they've evolved to only be able to eat goldenrod at some stage of their life cycle. As you might imagine, some of them have some pretty amazing coloration, like the goldenrod crab spider (Misumena vatia) and the goldenrod bug (Megacyllene robiniae). It's worth stopping to look closely and see who you can find among those little flowers.

Spider in the Goldenrod
Goldenrod spider by 'Lady-bug'
Megacyllene robiniae, Locust borer, Goldenrod bug
Goldenrod bug by 'Flatbush Gardener'

In the wild: Goldenrod grows all over, with different species favoring different conditions. There's always a good showing at Lake Artemesia (join us on a walk there on October 9)...what's your favorite patch?

In your yard: Many species are easy to grow; in fact, a little too easy sometimes. Cullina warns against S. canadensis and S. graminifolia as being too aggressive. Out of the ones we've tried in our yard, anise-scented (S. odora) and zig-zag (S. flexicaulis) seem best behaved.

Tuesday, September 21, 2010

Come Visit Natural Capital HQ on the Takoma Green Homes Tour

We're pleased to announce that our house will be one of the dozen or so homes on the Takoma Green Homes and Gardens Tour on Saturday, October 2. Please stop by and say hello -- we'd love to meet our readers! Come check out not only our solar panels but also our gardens landscaped almost entirely with native and edible plants, and other miscellaneous environmentally friendly things around the house and yard.

This green old house
Saturday, October 2
11:00AM - 5:00PM

709 Ritchie Ave.
Silver Spring, MD 20910

You can request a guide to the full Takoma tour here.

The tour also coincides with the wider DC Area Solar Homes Tour, which spans both Saturday and Sunday.

Sunday, September 19, 2010

Calendar: Public Lands Day and Walking/BikingTown DC

Even more is going on than usual this weekend as two major sets of outdoors events are scheduled on top of a regular weekend of hikes and activities.

But first, a plug for our own walk: on Saturday, join us for two hours of wild food foraging, including looking for chestnuts, black walnuts, and wild grapes. We'll be done by 11:00, plenty of time to join one of these other events. Register here.

All weekend you can join free tours with WalkingTown DC and BikingTown DC, a twice-annual event. Many are more oriented toward history and architecture, but there's always a sprinkling of nature-themed tours. They include:

a walking tour of the Arboretum Saturday at 10:00AM
a walking tour of restoration projects along Watts Creek Saturday afternoon at 1:00PM
a walking tour of Roosevelt Island Saturday at 3:00PM and Sunday at 3:30PM
a walking geological history tour Sunday at 9:00AM
a bike tour of Rock Creek Park Saturday at 9:00AM

Be sure to visit the website and register soon as many tours fill up -- they're free!

National Public Lands Day is also this Saturday. It's an opportunity to give back to the many city, county, state, and federal parks that give us so much joy throughout the year. You can find an event here; some highlights from the DC area include cleanups at Kenilworth Aquatic Gardens and the Carderock climbing area, invasive plant removal at Greenbelt Park and the Northwest Branch, and trail work at Great Falls.

As always, there's lots more on our calendar. We'll see you out there!

Thursday, September 16, 2010

LOOK FOR: Ragweed (It's Causing Your Hay Fever)

If you don't have a hard, cold place in your heart for ragweed, I can only conclude that you either a) are one of the lucky 70+ percent of the population that doesn't get hay fever, or b) don't know what's causing you to sniffle constantly from August into September. I do have hay fever, and I know one of the worst perpetrators. Permit me to tell you about it.

Ambrosia artemisiifolia | Alsemambrosia - Common ragweed
Common ragweed (Ambrosia artemisiifolia)
by AnneTanne
You've probably walked by ragweed hundreds of times without even noticing it. It's a pretty non-descript plant that sends up stalks of non-descript green flowers.* Of the 17 species of ragweed in North America, not surprisingly, the most common is common ragweed (Ambrosia artemisiifolia), which grows to about 3 feet and has almost frilly leaves with many lobes. I've also come across impressive patches of great ragweed (Ambrosia trifida), which can grow 9 feet or taller; its leaves tend to have just three to five lobes (and sometimes they're just oval).

It's the non-descript green flowers that are my nemesis: instead of developing pretty, frilly things to attract pollinators, ragweed developed the ability to produce massive amounts of airborne pollen that floats around looking for other ragweed plants to fertilize. If you look closely at the individual flowers in a stalk, they're all pointing down, so they can just drop their pollen on the breeze. A billion grains of pollen per plant, in fact.

It's the carpet bombing strategy of the plant world.

Great Ragweed
Giant ragweed (Ambrosia triloba) by 'milesizz'

These innocent grains of pollen are dependent on the wind to take them where it may. And wind goes many places. Down your street, say. And, eventually, up your nose. And then, as WebMD describes it,

Your immune system reacts to them as if they were a threat...Specialized immune cells start churning out antibodies to proteins in the pollen. The ensuing cascade of biochemical reactions floods the bloodstream with histamine, a compound that causes all-too-familiar allergy symptoms...[including] sneezing, sniffling, nasal, puffy eyes, itchy throat, and even hives.

Pass the antihistamines, please.

Ironically enough -- did you notice this above? -- the scientific name of the ragweed genus is Ambrosia. A contributor to the Wikipedia entry on ragweed speculates that this might be for the "immortal" root of the word ambrosia. But these plants are annuals -- they live less than a year. That's why they have work so hard at reproducing. Any other guesses on what Linnaeus was thinking with that name? There's a good chance he had no idea about the link to hay fever.

Ambrosia trifida GIANT RAGWEED
Close-up of ragweed flowers by 'gmayfield'
In the wild: You'll often find ragweed in disturbed places like roadsides, abandoned fields, and stream banks, especially if there's good sun. For example, there's a lot of it growing in back of the field behind Takoma Middle School, down the street from our house.

In your yard: This is a native plant that serves as food for many insects and birds. But it's doing fine on its own in the wild, thank you very much. You really, really don't need to grow more. Please.

*Thought ragweed had yellow flowers? You're not alone, judging from my search for photos for this post. But that's goldenrod. More on that next week!

This picture just makes me want to sneeze.
Photo credit: 'pawpaw67'

Tuesday, September 14, 2010

A Trip Report, a Song, and a Recipe: Paw Paws on the Potomac

One of the best parts of keeping a nature journal is knowing when to look for things. And one of the best parts of leading nature walks is having a dozen pairs of eyes all looking for things with you (as long as they're willing to share!). It doesn't always work -- weather can be unpredictable, shifting seasonal patterns off by a few weeks in one direction or another. But when it works it's so sweet.

Sharing pawpaws
And it was literally sweet to find ripe pawpaws on Saturday, with a lovely group of folks from around the DC area. The fruits are just starting to drop, so keep an eye out over the next few weeks and you may be in for a treat. One of our walkers was reminded of an old song:

Pickin' up pawpaws and puttin 'em in her pockets...way down yonder in the pawpaw patch

Listen to the tune and you, too, can have it stuck in your head all week!

cracking open walnuts
Cracking and eating black walnuts

We also found black walnuts, as we'd hoped (Matt brought a few extras just in case). We spent some time along the river cracking them open with rocks. It's easy to imaging people doing the same thing hundreds of years ago, in the same spot: we were just across the river from the fishing weir at Scott's Run.

This pawpaw and black walnut combination reminded me of a cookie recipe that Matt got when he first started learning about wild edibles, from his classmate Leslie Plant:
Pawpaw Cookies

2 cups flour
1 teaspoon soda
1 teaspoon salt
1/2 cup butter
1 cup sugar
2 eggs
1 teaspoon grated lemon rind
1 1/2 cups mashed pawpaw pulp (for best taste, don't scrape too close to the skin)
1 cup chopped black walnuts

Preheat oven to 350 degrees. Sift together flour, soda, and salt. Cream butter and sugar. Beat in eggs. Add lemon rind, flour mixture, and pawpaw pulp. Fold in black walnuts. Drop on greased cookie sheet and bake for 15 minutes.

Here's a full list of the things we stopped to look at on our walk. Links are to previous posts on the Natural Capital. Asterisks are the ones we ate, or talked about eating.

tiger swallowtail on woodland sunflower
Tiger swallowtail on woodland sunflower
Woodland sunflower (Helianthus divaricatus)
Wingstem (Actinomeris alternifolia)
New York ironweed (Vernonia noveboracensis)
Mistflower (aka Wild Ageratum, Eupatorium coelestinum)

With fruits, berries, nuts, or seeds
Spicebush* (Lindera benzoin)
Wood nettle* (Laportea canadensis)
Stinging nettle* (Urtica dioica)
Jimsonweed (Datura stramonium)
Wild Rye* (Elymus sp.)
Black walnut* (Juglans nigra)
Wormwood/Sweet Annie (Artemesia sp.)
Bitternut hickory (Carya cordiformus)
Wild grapes* (Vitis sp.)
wild rye and the stems of wingstem
Wild rye and the winged stem of wingstem

Poison ivy (Toxicodendron radicans)
Box elder (Acer negundo)
Blackberry* (Rubus allegheniensis)
Asiatic bittersweet (Celastrus orbiculatus)
Virginia creeper (Parthenocissus quinquefolia)
Wild ginger* (Asarum canadense)

Sound fun? Our next walk will be to look for more nuts, including a spot we know where chestnuts grow, and whatever else we stumble upon along the way. Sign up here.

Sunday, September 12, 2010

Calendar: Early Fall

We're back from a fantastic trip to Colorado (pictures here) to find that it's becoming fall here in DC. I was in denial over the fact that it's mid-September until I heard today's weather report: high in the low 70s? Really?

Blue-headed Vireo
Vireo by Art Drauglis
Well, some of the folks on our calendar anticipated this turn of seasons with fall-themed events. They include:

A Montgomery County park naturalist is leading a free hike at Tridelphia Reservoir on Thursday, in part to look for fall songbird migrants. Call 301-924-4141 for more information or register here.

Huntley Meadows is hosting a Fall Birds and Bagels even Saturday at 8 AM. Your $8 registration fee includes breakfast, which might take the edge off of getting up so early. Register at 703-768-2525.

There's also a fall warbler walk scheduled at Brookside Nature Center on Sunday morning at 9:30. $6; register here.

The first in the Audubon Naturalist Society's Fall Walks is on the C&O towpath near Sharpsburg. It's at 8 AM on Sunday (but no breakfast). $30; register here.

And Sunday afternoon at 2:00 there's a fall equinox hike scheduled at Potomac Overlook Park. Call 703-528-5406 for reservations.

As always, there are lots more events -- including an opportunity to go see a Talk of the Nation program on the Gulf oil spill, a couple of bat programs, and lots of hikes and cleanups -- on our calendar.

Thursday, September 9, 2010

LOOK FOR: Black Walnuts

Around this time of year, black walnut trees are cursed by homeowners throughout the DC area as they start dropping their nuts on roofs and driveways. But we say, when life gives you walnuts, make...walnuts!

Photo by the Natural Capital
Our native black walnuts (Juglans nigra) aren't the English walnuts (Juglans regia) you'll buy in the store -- and you'll pay a lot more for them, if you can find them at all. They're valued by many bakers for the special something they can add to cookies, brownies, and other treats.

People tend to have strong opinions about whether black walnuts taste good for eating out of hand. Wild edibles author Sam Thayer writes of telling a friend they taste like paint: "After cracking and eating a half dozen, he looked at me and said, 'You're right. They do taste like paint...Really good paint.'"

Want to taste for yourself? First, find some nuts. They'll fall on the ground when they're ripe, and that's the easiest way to find them. You're looking for lime-green balls about the size of a racketball. Actually, even better than bright green, you want ones that have ripened to the point that they're getting a little yellowish, with black spots. Like any ripe fruit (and this is actually considered a fruit, botanically), the flesh should have a little give to it.

(Note: hickory nuts, which are also edible, have a similar green fleshy husk, but they're smaller and the husk is divided into four sections.)

Black Walnut Hulls
Photo credit: knitting iris
Before you go picking up a bunch of walnuts or testing their softness, beware: the outer green husk (and the juice it leaves behind on the inner nuts) will stain your hands brown. For weeks. Washing won't do a bit of good.

So, if you're going to be handling walnuts, and you care about whether your hands are dyed funny colors, WEAR RUBBER GLOVES.

Unless you want to dye things brown, you don't need that fleshy husk. To remove it, you can just stomp on the walnuts where you find them on the ground, and (with your gloves on) remove the hard nut from the middle.

Black Walnut
Photo credit: Erika F.
The nutmeats inside that hard shell are edible right away. But many people recommend letting them dry before you crack open that hard shell. It improves the flavor, and makes it easier to dig the (now slightly shrunken) nutmeat out of the shell when you do crack it open. It also allows that brown-staining juice to dry, so that you can work with the nuts without gloves on.

To dry the walnuts, once the husk is removed, spread them out on thick newspapers, cardboard, or old window screens, or hang them up in mesh onion bags. Let them sit for a couple of weeks somewhere with good ventilation. (But not outside, or the squirrels will steal them!)

Photo credit: dans le grand bleu
Whether you let them dry or not, cracking into a black walnut shell is quite a challenge. A normal hand-held nutcracker won't do it. On the trail, you might have luck cracking walnuts between two rocks. We've been known to hang out by the fire and crack them open with hammers on a winter night. To keep the nutmeats more whole, you can buy special heavy-duty nutcrackers meant especially for walnuts, or use a slowly-tightened vise.

As you're using any of these methods, stop for a moment and appreciate how strong a squirrel's jaws and teeth are, to be able to get into these nuts.

Is it worth all this work? You'll just have to try it and decide for yourself. Then come back here and let us know what you think.

In the wild: Walnuts are common throughout rich, moist woods in the Washington, DC area, and also are planted in many yards. They are lovely trees with dark, ropy bark and compound leaves. The easiest way to find them at this time of year, though, is to look for the nuts falling on the ground.

In your yard: Black walnut makes a beautiful shade tree. We'd recommend planting it away from your house and driveway, so they're not pelted with nuts in the fall. The roots of walnuts create a chemical (juglone) that impedes growth in many common garden plants, including tomatoes. However, many native species have co-evolved with walnuts and are unaffected by this chemical.

Sunday, September 5, 2010

Calendar: On the River

If all goes as planned, as you read this, we'll be canoeing for several days on the Colorado River in western Colorado. And so, a few highlights from this week's calendar that happen to be along rivers (though ones a little closer to home):

As of my writing this, there are still a few spots open in our Saturday walk to go look for ripe pawpaws (and eat them) along the banks of the Potomac River. Sign up here.

The Surfrider Foundation is sponsoring a water-based cleanup of the Potomac on Saturday, between Thompson Boat Center and Key Bridge. "Bring your surfboards, paddleboards, kayaks, canoes, or any other non-motorized watercraft," they say.

Potomac Overlook Park has a program every Sunday afternoon with refreshments, games, and hands-on nature exhibits.

And, this week and every week until October 29, you can take a free boat ride on the Anacostia River from Bladensburg Waterfront Park -- Tuesday through Friday at noon, or Saturday and Sunday at 5:00. Everyone thinks the Anacostia is a wasteland, but don't knock it til you've tried it -- we've seen some beautiful things on that stretch of river.

Also see our list of places to rent canoes and kayaks around the DC area -- including at Bladensburg, and spots along the Potomac that might enable you to hook up with the Surfrider cleanup.

As always, there are plenty of land-based adventures as well on our calendar. Have a great week!

Canoes for Rent
Photo credit: M.V. Jantzen

Thursday, September 2, 2010

Things to Look for in September

We're visiting family in Colorado for the next week, so you guys will have to keep an eye out for all of these for us and let us know what you're seeing! Links are to last year's September posts:

Spicebush berries by The Natural Capital

Spicebush is a common understory shrub in our local forests. In the early spring, it's got pretty yellow flowers. Over the course of the summer, the pollinated flowers transformed into little green berries. And soon, they will be turning bright red.

Also, keep an eye out for spicebush swallowtail caterpillars, who you can sometimes found curled up inside a leaf. In my opinion, they're one of the best-looking caterpillars around!

pawpaw fruits
Pawpaws by dmitri_66

Pawpaws are the largest fruit native to the DC area. In groves of mature trees, you can find them littering the ground, ready for eating. Of course, you'll have to beat the raccoons and opossums to them.

Chicken of the woods by girlguyed

Chicken of the woods is a hard-to-mistake and hard-to-match mushroom. We found several with all the rain in August...keep an eye out in September as well.

Male goldfinch by ehpien

Goldfinches live in the DC area year-round, but we seem to see more of them at this time of year as they come to feed on the seedheads in our flower garden. They're such a pretty little bird.

What else are you seeing outside? We'd love to hear about it.