Do Plants Behave?

Last month the PBS program Nature had a fantastic episode about plant behavior -- a controversial term. Do plants really "behave"? This show argues yes: plants can communicate, move purposefully, and compete selectively. They just do it in ways that are much harder to observe than the animal behaviors that usually make it into nature documentaries:

• Parasitic plants use their sense of smell to choose the best host plants, and grow toward them.
• Some plants can change their blooming pattern and chemical composition to avoid overpredation -- and pick up cues to do this from other plants that are getting eaten.
• Some plants can recognize siblings, and their roots grow less competitively with their siblings' roots.
• A vast underground network of fungi not only takes carbon from trees in exchange for nutrients, but actually helps shuttle carbon to baby trees.

In another interview, one scientist featured in this episode says, "I was raised to believe that plants are plants. You eat them, you grow them, and they look pretty, but this is suggesting that there is a lot more to them than just that. I really think that we’re at the cusp of a real paradigm shift and that people are going to be viewing plants very differently in the next ten years."

Check it out:

Watch What Plants Talk About on PBS. See more from Nature.

LOOK FOR: Katniss (a.k.a. Wapato, Duck Potato, Arrowhead, Sagittaria)

I finally got around to reading The Hunger Games this summer. The main character, Katniss, has grown up hunting and foraging in Appalachia, which turns out to be a real asset when she is forced to spend weeks fighting to the death with other teenagers in a large expanse of forest. I haven't read a novel with so much foraging in it since My Side of the Mountain.

Photo credit: Jerry Oldnettel

But it drove me crazy that I didn't know one of the main vegetables she relies on: katniss. When she was a child, Katniss's father told her: As long as you can find yourself, you'll never starve.

I was too engrossed to put the book down and look it up, but as the story went on katniss sure sounded a heck of a lot like a plant I know by three other names: wapato, duck potato, or arrowhead (for some reason "duck potato" always comes to mind first -- what a great name!).

This abundance of names is why botanists like Latin names (in this case, Sagittaria). It's not just to be arcane: they help make sure we're all talking about the same plant.

And sure enough, katniss is an Algonquin name for Sagittaria. It's another nice link to the main character: she's not just a forager, but an expert archer -- just like Sagittarius.

And you can see from the leaf how the plant got its name:

Photo credit: Tom Brandt

The USDA plants database lists 10 different species of Sagittaria as growing in the mid-Atlantic. They've all got arrowhead-shaped leaves -- some skinner than others.

There are other wetland plants with arrow-shaped leaves, but you can tell Saggitaria from its beautiful vein pattern: all veins starting from a single point at the stem, with some pointing down to end in the pointy bottoms of the arrowhead.

Sagittaria was cultivated by native people of North America for its tubers, which are also eaten by ducks, geese, and muskrats. Sam Thayer gives an extensive account of how to find and harvest the tubers in his excellent book The Forager's Harvest.

In some parts of North America (including Sam Thayer's Wisconsin) there are wetlands with acres of Saggitaria growing in clean water, just begging to be eaten. The Washington, DC metro area is not in that category. All of our water is polluted, and while Saggitaria is growing somewhere in most wetlands I've visited, it is not abundant. It's just not realistic to get up your hopes of responsibly foraging for katniss in our area.

But you can find it, and appreciate knowing the connection to foragers in centuries past...and in the futuristic world of the Hunger Games.

In the wild: There's quite a bit of Saggitaria growing in the C&O Canal between the westernmost parking lot at Carderock and the Marsden Tract Campground (map). I'd love to hear about other patches!

In your yard: We've had a single Sagittaria growing in our pond for a few years...the leaves are smaller than in the wild, possibly because it wants deeper mud to form bigger tubers? We haven't mucked around in the water to figure out what's going on. Right now I'm just enjoying the lovely flowers!

Photo credit: Tom Brandt

LOOK FOR: Rose Mallow, our local hibiscus

I always thought of hibiscus as a tropical flower. It's the kind of thing you expect to see printed on Hawaiian shirts, or tucked behind a hula dancer's ear. But we've got native hibiscus right here in DC.

Hibiscus at Jug Bay by the Natural Capital

Unlike the bright red tropical hibiscus, our native hibiscus has five petals that can range in color from light pink to white, with a darker magenta center. Protruding from that dark center is a showy yellow set of reproductive parts: a tube covered in pollen-producing stamens, with five pollen-collecting pistils branching out on the end. The flowers can be six inches across, on stalks that reach 5 (or more) feet high. It's quite an impressive plant.

Bee pollinating hibiscus, by Mean and Pinchy

The name Hibiscus covers a large genus of related plants. We have at least two native species in the DC area: Hibiscus laevis, often called halberd-leaved rose mallow, and Hibiscus moscheutos, or swamp rose mallow.  We usually are happy to just say "hibiscus" or "rose mallow," and leave it at that.  But if you want to get to the species, remember that laevis means smooth -- Hibiscus laevis has smooth leaves; Hibiscus moscheutos has leaves with hairy undersides.

The genus Hibiscus also includes the imported Rose of Sharon (Hibiscus syriacus), which many people have in their yards. But the flowers of Rose of Sharon don't get nearly as large as our native hibiscus -- maybe 4 inches across as opposed to 6 inches or more.

Pink rose mallow by Urtica

In my experience, the best time to catch rose mallow blooms is in the morning. By afternoon, they fold up as protection against the heat. Each flower is short-lived, but each plant produces many flowers. And each flower produces a seedpod about an inch in diameter. These can be showy in their own right in the fall and winter, when they bust open along five lines, leaving an open pod that looks almost like a dried flower itself.

In the wild: Rose mallow likes wetlands. We've seen it growing at Roosevelt Island, and there's lots of it at Jug Bay. I'm sure it's in other spots as well.

In your yard: We're growing rose mallow that we started from wild-collected seed in our raingarden and in our dry backyard; it seems to be thriving in both locations. So, even though it grows in marshy areas naturally, it doesn't seem to require them.  It does need at least several hours of sun to bloom well, though.

Where have you seen hibiscus growing? Leave us a comment!

LOOK FOR: Blue Flag Iris

The first spring that we moved into our house, I was thrilled to discover an abundance of bearded irises in our front yard. Along with some daffodils and tulips and a crepe myrtle, the irises are among the few non-edible, non-native plants that we've kept, because they're just so pretty. But their place in my heart may soon be usurped by our thriving native blue flag iris, which is blooming right now.

Blue flag iris on the Northwest Branch

Blue flag iris grows in a different environment, mind you -- it's a wetland plant. There are two species native to this area; we're in the overlapping part of the range of northern blue flag (Iris veriscolor) and southern blue flag (Iris virginica). Both are a little smaller and more delicate feeling than most cultivated irises -- but they've still got the long, spiky leaves and that amazing flower that's impossible to mistake for anything else.

The two native species are hard to tell apart, and I won't bore you with the details. But there is one similar non-native iris you may see growing in wetlands -- yellow flag iris (Iris pseudacorus), which, as you might guess from the name "yellow flag", has bright yellow flowers. It's an import from Asia, and there's some concern that it's displacing blue flag in natural areas. Sure enough, there's been more and more yellow mixed in with the blue flag in our favorite spot over the last several years. We really should talk to someone about getting it out of there.

Blue flag iris in our pond

In the wild: We've seen blue flag scattered along the C&O canal here and there, and it's growing at Lake Artemesia. I'm sure there's some at Kenilworth Gardens, and it's worth looking at Huntley Meadows and Jug Bay. Or, if you're heading to look at the mountain laurels along the Northwest Branch of the Anacostia that I wrote about on Tuesday, there's some blue flag across the river. Rather than following the trail on the right hand side of Burnt Mills dam, cross the river (using the sidewalk along Colesville Road), follow the trail upstream on the left hand side, and keep an eye out to your right along the water.

In your yard: We've got a clump of blue flag iris submerged in our pond, and a few more in our rain garden. They seem to do well in both locations. And I love their spiky foliage, even when they're not in bloom!

LOOK FOR: Bluebells, Clumps of Heaven Here to Ring in Spring

Photo credit: The Natural Capital

Does it seem like all of our posts lately include the sentence, "it is a rite of spring for us to look for ___________"? Well, add one more to the list. The bluebells are coming out, and you can bet we'll be looking for them.

And they're not hard to find. In fact, in the right places, they're downright prolific. Bluebells like the bottomlands along streams and rivers. There are many stretches of parkland along the Potomac where they form 14-inch tall blue carpets for a few weeks every April.

But before turning blue, bluebells start out pink. The clusters of flowers don't open all at once, so you'll often see a bunch of puckered-up pink buds mixed in with the blue flowers. The stem arches over and the trumpet-shaped flowers really do hang like a cluster of little bells ready to ring in spring.

Photo credit: Dancing Nomad

Even when they're not blooming, the foliage of bluebells can be distinctive. The broad leaves are smooth and light green, almost dusky when they first come up. But by midsummer, you won't even know they're there. The leaves of bluebells will die back by June, leaving their roots charged up and ready to go next spring.

William Cullina says of bluebells: "As best I can determine, Mertensias are not plants at all, but delicate clumps of sky, thinly disguised and sent here for a few weeks each year to bring us earth-bound folks briefly closer to heaven."

Amen.

In the wild: Look in any of the wooded parks in the flood plain along the Potomac for big patches of bluebells -- including Scotts Run, Turkey Run, McKee Beshers, and some other stretches of the C&O Canal. They were already blooming last Saturday in some south-facing stretches of the Billy Goat C trail around Carderock. There are also some big patches in Rock Creek Park. We'd love to hear about other locations!

In your yard: Bluebells need moist, but well-drained, soil. They do best in deciduous shade -- they need the spring sun, but don't naturally grow in places where they'll get full sun in the summer.

Do you have a favorite spot where you find bluebells? Have questions about them? Leave us a comment!

Bluebells at Scott's Run by the Natural Capital

Trip Report: What's Blooming at Carderock

view of
Scott's Run by Carly & Art

On Saturday we led a wildflowers and wild edibles walk at Carderock. We had a beautiful sunny day, but it was chilly -- so we warmed up beforehand with a little spicebush tea. Then we spent a couple of hours stopping along the Billy Goat C trail to look at what's coming up.

We picked Carderock for a walk on the early side of spring wildflower season because the Potomac runs pretty much west-east there. At Carderock, the banks along the river face south -- giving them some extra sun exposure and warmth. Flowers come up noticeably earlier there.

Even within the Billy Goat C trail, there were noticeable differences -- the section to the east of where we parked was further along than the section to the west. In contrast, if you went over to Scott's Run, directly across the Potomac, the north-facing banks there won't have some of these flowers for a week or two yet.

Here's what we saw:

Dutchmans breeches by Carly & Art

Blooming
Virginia bluebells
Cut-leaf toothwort
Golden ragwort (just starting)
Spring beauty
Spicebush
Skunk cabbage
Wild blue phlox (just starting)

Sending up leaves
Wild ramps/leeks (see our post on the flowers)
Early meadow rue
Trout lily (we saw some blooming after the walk!)
Stinging nettles
May apples

With buds
Pawpaw (see our post on the fruit)

And some invasive species
Garlic mustard is coming up
Lesser celandine is starting to flower
Bush honeysuckle is leafing out, before most native shrubs

It was an added treat for us to meet some Natural Capital readers! Carly and Art took lots more pictures, which you can see here. You can sign up for one of our upcoming walks here.

May apple emerging by Carly & Art

Wild ramp (from our yard) by Carly & Art

LOOK FOR: Bloodroot, a Delicate White Flower with a Gory Name

Photo credit: squamatologist

Bloodroot is one of our favorite spring flowers. Each plant blooms only briefly, and there's a window of only a few weeks that the bloodroots bloom at all. It's one more thing that inspires us to spend as much time as possible in the woods at this time of year.

But beyond the ephemeral, catch-it-while-you-can nature of these flowers, why do we like them so much? I'm not sure I can put my finger on it. There's just something beautifully simple about the pure white blooms. The flowers can be about 2 inches wide, with at least 7 petals per flower (and up to 12 petals).

And why the gory name for such a lovely plant? If you were to dig up up a bloodroot plant, you would see that the root is red. In fact, when it is cut, the root oozes red juice that's just about the color of blood. It's downright creepy looking.

But please, just take our word for it -- don't go digging. These lovely flowers are struggling to maintain a foothold against invasive species that crowd them out. Then, once they make it through the gauntlet of English ivy, garlic mustard, and lesser celandine, they've got to evade the overpopulated deer, who are happy to make bloodroot part of their early spring salad mix.

Photo credit: AriCee

But somehow, some bloodroots make it through every year. If you catch them early enough, you can see how the whole bloodroot plant unfurls itself, a single flower bud wrapped inside a single leaf, emerging from the forest floor. That leaf can grow to be as big as an outstretched hand, persisting into the summer. The knobby shape is distinctive long after the flowers have faded away.

You can use those eye-catching leaves to help you find bloodroot seedpods in the summer. They're notable because the seeds include a gooey coating whose entire purpose is to attract ants. Once the seeds fall to the ground, ants will carry them to their nests, eat the coating, and dispose of the seeds intact. William Cullina writes of watching ants carry away an entire seedpod worth of seeds in half an hour.

Native Americans had many medicinal uses for bloodroot root, and they also used it as a red paint and dye. It is still sometimes sought as a medicinal herb, especially as a treatment for skin cancer, but is generally considered toxic -- and sometimes causes a skin reaction similar to poison ivy. Another reason not to dig it up!

Photo credit: Carly & Art

In the wild: Look for bloodroot in areas that have plenty of shade in the summer. You'll find it scattered through many wooded parks in the DC region. It's not uncommon, but the timing can be trickier than the location.

In your yard: Bloodroot would love a spot that will stay shady, cool, and moist (but not wet) in the summer. They're a little tricky to start on your own from seed (the seeds must stay moist), but some native plant nurseries sell them. Check out the native plant sale at the National Arboretum on Saturday!

LOOK FOR: Spicebush Flowers, North America's Answer to Forsythia

Photo credit: aecole

Along one side of our yard, our neighbor has a forsythia hedge whose cheery yellow flowers are a magnificent joy in spring. But you won't find forsythia in the woods (at least, not yet):  it's from China. Instead, we look every year for the less showy but equally cheery flowers of the spicebush as they emerge to light up the understory of our local forests. On our hike yesterday, they looked like they were ready to burst open any day now.

For us, spicebush is a way to mark the passing of the seasons. We wrote about spicebush last September, when the bright red berries were marking the beginning of fall. Now is the time to look for the flowers that create those berries: they're a harbinger of spring (and much more reliable than groundhogs).

Photo credit: Wrenaissance

The flowers of spicebush appear in clusters along the stems, before the leaves emerge. Each flower has five small petals. (For comparison, forsythia has only four petals per flower. So does witch hazel, whose wispy yellow flowers otherwise can seem quite similar -- except that they bloom over the winter.)

Between the early spring flowers and the vibrant red berries, we're mystified as to why spicebush isn't a more common plant in yards and other ornamental plantings. It also has high wildlife value -- it serves as a host plant for beautiful spicebush swallowtails and promethea moths, while the berries feed birds and other critters.

The spicy twigs and berries of spicebush (think allspice) also have been used by humans for teas and flavorings for centuries (maybe millenia). They aren't attractive to deer, though -- which likely explains why spicebush remains common in our local woods even as the out-of-balance deer population is stripping out most of the rest of the understory.

If the deer are going to leave us just one shrub, we'll take spicebush, and with pleasure. It's a great way to greet the spring.

Photo credit: Janet Powell

In the wild: Spicebush is one of our dominant understory shrubs.  One of the most impressive areas we know is in Rock Creek Park, in the section east of Boundary Bridge. But you'll probably see some spicebush in just about any woods in the DC metro area.

In your yard: Spicebush needs shade, but a few hours of sun will encourage them to flower more and set more fruit. They can also suffer if they get too dry, especially as they're getting established -- they'll do best with reasonably moist soil.

Have a favorite spicebush spot? Questions we can answer? Leave us a comment below!

LOOK FOR: Fairy Spuds, More Commonly Known as Spring Beauties

Photo credit: Cowtools

Spring beauties are not a showy flower, but we find their little blooms dainty and adorable. They're one of the first to bloom among the flowers called spring ephemerals: perennial flowers that emerge every spring on the forest floor, before the trees leaf out, then fade into the background (or die back entirely to the ground) until next spring. They're also one of the longer-lasting blooms, so you've got a wider window of opportunity to find them.

We actually start looking for spring beauties in January. Not the flowers, but the little leaves. They're skinny like a little blade of grass, but more succulent -- spring beauties are actually related to purslane. (And like purslane, the leaves are edible.)


By mid-March, the spring beauties are blooming. The flowers are small (maybe 3/4" wide) and low to the ground -- the entire plant usually doesn't grow any taller than 4 to 6 inches. At any other time of year, they'd be easy to overlook. In early spring, though, they're a major part of the show before other things start blooming.

The flowers have 5 petals that can be white or light pink. If you look closely, you'll see they're candy-striped with thin pink lines pointing to the center of the flower. And just in case that doesn't tip off the pollinators well enough, the center opening of the flower is highlighted with little yellow spots.

Watch for how the flowers react to the weather. On a sunny day, they'll open wide. But with clouds, the petals fold back up and wait for better weather. It's another thing we love about these plants.

Photo credit: cyanocorax

By early summer, the flowers and leaves of spring beauty will shrivel up and die back to the ground. But several inches below the ground, the plant is storing energy for next spring in a little corm that can be as much as 6 inches underground. We've heard these tubers called fairy spuds -- they're starchy and edible when cooked, but each one is tiny. It would take an awful lot of energy to dig up enough fairy spuds to make any kind of meal. But apparently Native Americans and early colonists found them excellent.

We've tried a few fairy spuds from our yard -- but I think I prefer to see the flowers.

Photo credit: jbaker5

In the woods: Spring beauties can be prolific where they're not overgrazed by deer. We've come across areas that are carpeted with them. They'll bloom first on slopes that face south.

In your yard:  We love the spring beauties we've planted in a shady spot in our backyard. They're a great reminder to get out into the woods and see what else is coming up.


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LOOK FOR: Skunk Cabbage, First Flower of the Year

If you are afflicted with melancholy at this season, go to the swamp and see the brave spears of skunk-cabbage buds already advanced toward a new year...There is no can’t nor cant to them. They see over the brow of winter’s hill. They see another summer ahead.  -- Henry David Thoreau

Photo credit: gareandkitty

So much of the diversity in the natural world is the result of plants and animals figuring out how to survive in territory where others can't. A few weeks ago, we talked about rock tripe and how it manages to pluck enough moisture and nutrients from the air that it can colonize rock surfaces. Today, we bring you skunk cabbage -- which not only survives in a wetland environment many plants find inhospitable, but manages to attract pollinators in late winter, when nothing else is flowering.

To attract those pollinators, skunk cabbage relies more on guile than on charm. The skunk cabbage flower is no sweet-smelling bull's eye like most of the flowers we'll see later in the year. In fact, it stinks. Somehow, this plant has figured out how to make the molecules cadaverine (normally put off by rotting flesh) and skatole (otherwise found in scat). And with them, it attracts flies and beetles seeking a meal.

Photo credit: cyanocorax

The flowers continue their deception with a streaky reddish-purple spathe (the hood-shaped bract around the flowers) that is not unlike the color of carrion these insects are seeking. Inside that hood is a spadix made up of dozens of flowers, which get inadvertently pollinated by insects seeking a stinky bite to eat.

And skunk cabbage has one more trick up its sleeve (or should we say, spathe). Amazingly, it produces its own heat -- it may be 50 degrees or more above the ambient air temperature when the female flowers are in full bloom. This brings in more insects. For one thing, the warmth makes the stinky carrion smells more volatile. And insects might expect a piece of carrion to be warm, because of the heat released by the bacteria that are breaking it down.

Photo credit: Hljod.Huskona

But some insects just seem to want a little vacation from winter, like the rest of us do. Skunk cabbage can be warm enough to melt snow and ice, which surely feels good to insects trying to make a living at this time of year. The flowering season for skunk cabbage can vary by the weather, but in the Washington DC area they can start flowering in January and may go as late as March.

So, if you've been feeling the melancholy of the season, or having trouble seeing the summer ahead...it's a great time to start looking for flowers.

Photo credit: RupertG

In the wild: Skunk cabbage tends to grow in relatively flat areas that stay wet or muddy for most of the year. Look along small streams and seeps -- perhaps even growing in shallow water. There are many patches of skunk cabbage in Rock Creek Park and lots of other local parks. You may have noticed it in the summer with its large clumps of 2-foot-long leaves growing close to the ground. Right now you won't see much hint of the leaves -- you're just looking for the purplish spathes poking up from the ground.

In your yard: You won't have much luck growing skunk cabbage unless you've got a wetland in your backyard. If you do, go for it -- skunk cabbage are deer resistant, and that foliage is hard to beat.

LOOK FOR: Maple Sap (and Pancakes)

Photo credit: Dave Pape

Every spring, as temperatures rise, trees start to wake up from their dormancy. They've been storing energy  all winter as starch in their wood. But now, they want to use it to start producing leaves. And the way they get that energy to their leaves? Sap.

There's a particular window of opportunity for maple sap that is determined by temperature. When the temperature of the wood rises to the mid-30s, enzymes start to convert the stored starch into sugar. And once the tree warms up to about 45 degrees, the starch stops converting into sugar. In between, when days are relatively warm but the nights are relatively cold, pressure builds up in the tree, and the sap comes pouring out of any wounds -- particularly a wound that was put there intentionally to direct that sap into a bucket.

Photo credit: Friends Central School

If you taste the sap when it comes out of a tree, it will be only very slightly sweet; the sap is usually less than 3 percent sugar. In contrast, maple syrup is typically around 66 percent sugar. To get from 3 to 66 percent, you have to boil off an enormous amount of water. A single tap may release 10 to 20 gallons of sap from a tree over the several weeks that the sap is running. But that 20 gallons of sap boils down to less than a gallon of syrup. No wonder it's so expensive!

Photo credit: Lolly Knit

Several local parks have demonstrations of making maple syrup -- check out the calendars at Brookside Nature Center in Wheaton and Colvin Run Mill in Great Falls.

Meanwhile, we'll be curled up by our woodburning stove, watching a little pot of sap collected from our neighborhood maples as it slowly cooks down...the sweet taste of spring on its way!

Do you have any maple syrup stories to share? Leave us a comment.

LOOK FOR: Hemlock Trees (While You Still Can)

Photo credit: lumierefl

Eastern Hemlock (Tsuga canadensis) is a majestic tree sometimes called the "redwood of the East." They can form tranquil evergreen groves in the understory, but really, they're just waiting for their big break. When a tree falls and opens a spot in the canopy, hemlocks will shoot up -- eventually reaching heights of 80 or even 100 feet over their 350 year lifespan. In the second-growth forests of the DC area, though, you'll see only scattered trees, and they're rarely taller than 15 or 20 feet tall.

Because they're evergreen, this is a great time of year to look for hemlocks, when other trees have lost their leaves. The needles of hemlock will help you distinguish this tree from other evergreens in our area: they are flat, about 3/4 of an inch long, and grow in a plane off the twigs. The overall form of hemlocks can also be distinctive:  branches grow horizontally from the trunk, but are floppy on the ends as the twigs haven't hardened up yet. Up close, you may notice very small cones on the trees -- they look like pine cones, but much smaller.

Photo credit: DaveSF

The genus name, Tsuga, is a Japanese word supposedly meaning "mother tree." Unfortunately the relationship between North American and Japanese hemlocks is not so nurturing. Around 1911, some imported hemlocks bound for a Japanese garden in Richmond came bearing an insect known as the hemlock woolly adelgid (uh-DELL-jid). This relative of the aphid is just a minor pest in Japan, where it's got several predators and the trees have some natural resistance. For our local Tsuga canadensis, though, infestation by the woolly adelgid is usually fatal within 4 to 10 years.

It wasn't until the 1980's that people started noticing that the adelgid had spread from ornamental plantings in Richmond to native trees in York River State Park and Shenandoah National Park. By the mid-90's, the adelgid had spread to Connecticut and Massachusetts, and it is now considered established throughout the hemlock's eastern range, from Maine to Alabama. Experiments are being done with the release of adelgid-eating beetles from Japan, but results don't seem very promising, and many stands of hemlock have already been lost. (To see some of the destruction to old growth hemlock groves, see this video from the Charlotte Observer.)

Hemlock at Scott's Run by the Natural Capital

There are two morals to this story. First, garden with native plants, so that you don't unwittingly import a pest that will devastate an entire species. Second, get out there and appreciate what we've got, while you can.

In the wild: We're not aware of any really large hemlocks in the DC area (do let us know!) but there are still some small hemlocks scattered in our local forests. The most we've noticed are at Scott's Run Nature Preserve in McLean -- they grow right along several of the trails there (like the one shown here).

In your yard: It's probably better not to bother planting hemlocks unless and until someone figures out how to control the adelgids. Too bad, because they're beautiful trees.

LOOK FOR: Holly, a Symbol in Winter Long Before Christmas

Photo credit: Kevin H

Decking the halls with boughs of holly is a tradition that pre-dates Christmas by quite a while. Romans used holly as a decoration and a gift for Saturnalia, a festival that took place around the winter solstice. Similarly, the Celts would place boughs around their house in the winter for protection and good luck. These traditions were absorbed by the Christian church, and holly became a common Christmas decoration.

Although decorating with holly started as a European tradition, hollies are native to North America as well. Many species are quite different from our classic idea of a holly tree -- some lose their leaves, some have black berries. But Ilex opaca, known as American holly, has the distinctive spiny, evergreen leaves and bright red berries that have been treasured as a winter decoration for millenia. Early colonists noticed them, too, and holly became an entrenched symbol of Christmas in North America.

Photo credit: Steve Hersey

Holly berries are important food for birds, but poisonous to humans. Birds tend to wait a while into the winter before they start eating them -- repeated freezing and thawing can soften them up and make them more palatable. Meanwhile, we get to enjoy their decoration in the woods. The trees are dioecious -- meaning each tree is either male or female. At this time of year, if you spot a holly without berries, there could be several explanations: 1) it's a male; 2) it's a female without a male nearby; 3) its berries have been completely devoured relatively early in the season, or 4) it doesn't get enough light to set fruit.

In the wild: Ilex opaca is scattered throughout the woods of the Washington, DC region. They can grow up to 40 feet, but it's more common to see shorter trees. Now is a great time to spot them, because the evergreen leaves will stand out when other trees have lost their foliage.

In your yard:  Holly is a great addition to a yard: for winter interest, habitat value, and as an evergreen screen. They prefer acidic soil. European and asian species are also sold in nurseries; ask for the native Ilex opaca. Compared to imported species, the native should have the most wildlife value -- although birds will eat the berries of most species, insects that have evolved relationships with the leaves of the native may not be able to survive off imports. And those insects serve as more bird food, throughout the year. 

Do you have a favorite spot to find holly? Have you been seeing the birds go after the berries? Leave us a comment!

LOOK FOR: Persimmon, Fruit of the Gods

Photo credit: the Natural Capital

I have a very early (and not entirely pleasant) childhood memory of getting pelted with persimmons as my mother shook them out of a tree in the woods near our house. Sometime in my twenties I overcame this trauma, and now I am likely to be the one shaking them down. Their scientific name says it all -- Diospyros virginiana, the Virginian food of the gods.

Persimmons have come up with an ingenious method for protecting themselves until they're fully ripe: they are horribly, mouth-puckeringly astringent when immature. There is a common saying (among folks who eat persimmons, at least) that a frost makes persimmons lose this astringency. This is close, but not exactly true: persimmons ripen up around the time of our first frost, but the two events aren't related. We've found edible persimmons before a frost, and horribly astringent ones after frost.

Photo credit: Janet Powell

The real rule of thumb is that you only want to eat fruit that are gooey-soft and falling off the tree. Give the trunk a gentle shake and collect the fruits that fall. (Beware any fruit that are still attached to a twig when they fall: they weren't actually ready to come down yet.) Before you eat a whole fruit, take a small bite and wait a minute to make sure it's not going to make your mouth feel like it's been sucked dry: the puckering power of the persimmon is definitely related to how much you've eaten.

But don't let all this talk of astringency scare you off: when they're good, they're really, really good.

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At this time of year, you have two ways of identifying a persimmon tree: by bark, and by fruit. The bark is dark grey and chunky, broken up into squares. Learning to recognize it is key, because the fruits are usually well above eye level. When you see the bark, look up: the fruits are round and orange, about the size of a golf ball, hanging on the tree long after it has lost its leaves. Each fruit has a distinctive four-part sepal on top. There's nothing I can think of that you could confuse them with. So, shake away!

In the wild: Persimmons need sun to set a lot of fruit. You'll often see them on the edges of woods. We know of a few on the C&O Canal between Great Falls Tavern and the falls, and many along the Northwest Branch of the Anacostia north of Colesville Road. And we always keep an eye out for fruit along Eastern Avenue at Jecquie Park in Takoma, where there's a tall persimmon right next to the sidewalk.

In your yard: Persimmons can grow in a wide range of soils. You'll need sun, and room for a tree that will eventually be 20 feet or more. Edible Landscaping has a selection of saplings grafted from trees found in the wild with unusually large fruits. They appear to have also grafted them to be self-fertile, which is important, because wild persimmons have male and female trees.

Do you have a persimmon story, or a favorite spot where you find persimmons? Leave us a comment!

LOOK FOR: Witch Hazel, the Last Flowers of the Year

As one of the last things in the DC area to flower in the fall, witch hazel has a special place in my heart. It's not that the flowers are particularly showy -- the petals are just small yellow wisps, really. But the flowers of Hamamelis virginiana start blooming in October, and can keep going until Thanksgiving or even later.

Photo credit: Jim Frazier

Witch hazel (or witchhazel) is an understory shrub that grows up to 20 feet tall. Its flowers are about a half-inch to an inch wide, and they come in clusters of 3-5, on a little stalk coming off the twigs of the shrub. They'll form clusters of seedpods which explode when they're ripe, shooting their seeds up to 30 feet away. You may see some seedpods on the tree at the same time as the flowers are blooming.

Photo credit: poppy2323

There's another native species of witch hazel that, rather being the last to bloom this year, will be one of the first blooms of next year. Hamemelis vernalis often has redder flowers, and they're slightly smaller. We've never seen it in the wild, so let us know if you see some this winter! There are also Asian species of Hamemelis that are often planted ornamentally that flower in the winter.

Many people have heard of witch hazel because the bark and leaves have a long history of medicinal use as an astringent. But the "witch hazel" you can now buy in a store actually has very little witch hazel in it. It's made by soaking the leaves or bark in water, distilling it, then adding alcohol. People disagree on whether witch hazel actually has any effectiveness after the distillation process -- it may be the alcohol that's doing most of the good when you use this product. We've never tried making our own -- this tree just isn't common enough to justify it.

Photo credit: urtica

In the wild: Witch hazel likes moist soil, though we've also seen it on dry mountainsides. They're scattered along the Valley Trail in Rock Creek Park -- on our last hike we noticed several directly across Rock Creek from Picnic Area 8 that were in bloom. There used to be a nice stand of small witch hazels on the Rachel Carson trail north of Colesville Road, but a couple of years ago they were taken out by beavers. We'll have to check on whether they've managed to come back.

In your yard: Garden books recommend them, but the witch hazel we planted a few years ago still seems to struggle in the summer. All trees want a lot of water in their first year after planting, but this one perhaps more so.

Where have you seen witch hazel in the DC area? Leave us a comment below.

LOOK FOR: Wild Grapes

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I had a book of Aesop's Fables as a child, and the story I remember best is the story of the Fox and the Grapes. There's a big, juicy bunch of grapes hanging from a vine, and a fox is trying as hard as he can to get to them, but just can't quite reach. When he gives up, the fox says, "I don't want those grapes anyway -- they're probably sour!"

Sounds like the wild grapes of ancient Greece weren't too different from our own -- very tempting but very sour. Our native grapes are also very small. But we like them anyway...and like the fox in Aesop's fable, we'll go to some lengths to get some every fall.

Photo credit: terriem

Before you try to eat wild grapes, be confident in your identification. The leaves can be quite varied in size and shape, but generally have roughly toothed edges. The leaves may have three distinct lobes, or they may just hint at them. The vines climb with distinctive, curly tendrils that wrap around whatever they can for support.

As they get older, the vines shed their bark, giving them a shredded texture. It's not uncommon to see thick, peeling grapevines reaching far up into the canopy -- they've kept pace with the tree they're hanging from, making sure they can get sun for their leaves even as the tree puts on new growth.

Photo credit: Ivan0207

But you're looking for fruit that's within reach, which will likely be on younger vines. Clusters of wild grapes look something like miniature clusters of cultivated grapes. When ripe, they are dark purple, but (like cultivated grapes) they may have a blush of yeast on them that makes them look a little lighter. They have multiple crunchy seeds which take up a lot of the fruit. But the fruit that is there has an intense flavor.

There are several other small, purple fruits in the fall. Make sure you rule these out -- none of them are edible, and some are quite poisonous: virginia creeper (which has leaves made of five leaflets, and red stems on the fruit), Canada moonseed (whose leaves are a similar shape to grapes, but smooth, not toothed; each fruit has a single, moon-shaped seed), porcelain berry (also has grape-like leaves, but the berries are blue and white before ripening, not green like unripe grapes), and pokeweed (not a vine, but it can be mixed into thickets that also include grapes; fruits branch off a very straight stalk that's often reddish).

Enough warnings. We've taught 3-year-olds to reliably recognize wild grapes...you can do it too.

Photo credit: kretyen

In the wild: Wild grapes need some sunlight to fruit well but they also like the support of trees. They generally thrive where there has been a disturbance in the forest canopy, or on the trees on the edge of a forest. There are tons of grapes out there that you have no hope of reaching, but every once in a while, a younger vine will have some fruit low enough for you to get a taste.

In your yard: Wild grapes are a lot easier to grow than cultivated grapes, in the sense that they don't get as many pests and diseases. But the vines can grow up to 75 feet long. They'll do best in full sun, on a trellis. You can also try a more naturalistic planting, as long as there's something for the tendrils to wrap around for support.