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?

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 (Solidago nemoralis) by 'milesizz'

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.

Goldenrod spider by 'Lady-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.

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.

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.

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 congestion...red, 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.

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'

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.)

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.

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.

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!

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.

LOOK FOR: Wild Grapes

Photo credit: memotions

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.

LOOK FOR: Acorns of many shapes and sizes - an identification guide for 12 common oak species

There are 90 species of oak in North America. Their acorns are an important food for a broad diversity of wildlife, from insects to deer. And historically, they were a staple food for Native Americans in this area.

Oaks are generally split into two groups: "red" and "white." Red oaks have leaves whose lobes come to a point, with a little bristle on each point. Their acorns take two years to mature, so even as they're dropping this year's crop, they've already got half-grown acorns for next year. White oaks have leaves with more rounded lobes, typically lighter-colored bark, and their acorns take only one year to mature. But even within those two groups, there's a wonderful diversity of acorn shapes and sizes. Below are a selection of some of the acorns you might see in the greater DC area. (We've tried to line them up so they're to scale.) How many can you find in the wild?

Red Oaks

Northern Red Oak Quercus rubra	Southern red oak Quercus falcata	Black oak Quercus velutina
Willow Oak Quercus phellos	Pin oak Quercus palustris	Blackjack oak Quercus marilandica

White Oaks

White oak Quercus alba	Overcup oak Quercus lyrata	Swamp white oak Quercus bicolor

Chestnut oak Quercus prinus	Post oak Quercus stellata	Bur oak Quercus macrocarpa

One way to really get familiar with acorns is to collect them for Growing Native. The Potomac Conservancy will use them to replant buffer zones along the Potomac and its tributaries. This improves water quality and provides important wildlife habitat. You can donate collected acorns until October 26 in Virginia and October 31 in  Maryland and DC.

All photos by Steve Hurst at the amazing USDA-NRCS PLANTS Database, except the post oak acorns, which are from the magnificent old tree here at The Natural Capital headquarters.

LOOK FOR: Spicebush Berries

If you have ever been hiking in the woods in the DC area, chances are you've walked by hundreds of spicebush shrubs. They've got small yellow flowers in the spring, then they form a nondescript green backdrop in the woods for the rest of the summer. Until September -- when their berries turn bright red.

Spicebush can grow up to 20 feet tall, but we commonly see them at about 5-10 feet. The leaves have smooth edges and alternate along the branch. As fall progresses, the leaves will turn yellow.  The berries may remain on the shrub after the leaves have fallen off, but the birds may get to them first.

The twigs, leaves, and berries of spicebush all have a smell reminiscent of nutmeg or allspice when crushed.  Presumably, the Latin name Lindera benzoin was given as a reference to benzoin resin, which was used to make incense and perfume in Asia and Europe.  It's actually more related to laurels, including the bay laurel that gives us bay leaves.

Spicebush parts don't just smell good -- you can use them as a spice. The twigs can be brewed in hot water to make tea. Berries can be used fresh or frozen, as an allspice substitute. (Steve Brill recommends against drying.) We'll often cook them up with sliced apples to make a delicious topping for pancakes. Each berry has a single seed inside, which can be ground up with the rest if you're going to use it as a spice -- that's a lot less work than trying to get the seed out of each one. 

Photo credit: poppy2323

As you're looking for the berries, also take a peek if you see any leaves folded over. You might find the caterpillar of a spicebush swallowtail butterfly, whose only host plant is the spicebush. They're lovely black butterflies, but their caterpillars are adorable -- they have big eyespots that make them look like a cartoon snake. You might also find the caterpillar of a promethea silkmoth, a large and beautiful moth that we have seen far more as a cocoon hanging from spicebush than in any other stage of its life cycle.

In the wild: Spicebush is one of the dominant understory shrubs in our local forest.  In Rock Creek Park, we recently noticed large groves on both sides of the Valley Trail, in the section east of Boundary Bridge.

In your yard: Spicebush need 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.

Matt keeps a little stock of spicebush seedlings to put into clients' yards. They regularly get eaten up by spicebush swallowtail caterpillars in the summer. Most bounce back from the damage -- after all, these caterpillars have been eating these bushes for millions of years. And we love supporting the butterflies!

LOOK FOR: Paw Paws

The paw paw is the largest fruit of any native plant in our area. And you can eat it. And they should be ripening over the next few weeks. Need I say more?

Paw paw fruits have a green skin and soft yellow flesh, and are typically about the size of two golf balls stacked together. The flavor has been described as similar to many different things -- banana, custard, mango -- but really it has its own taste. Pawpaws can have an unusual aftertaste that limit me to enjoying one or two fruits. But those few fruits are such a treat when they come from the forest!

Paw Paw (Asimina triloba) is the northernmost member of the Annonaceae family, which includes other tropical fruits such as the soursop. I had always thought they were related to papaya, but apparently it is in name (and somewhat appearance) only.

Immature paw paw trees are abundant in the forests in and around Washington, DC. When young, they look more like an understory shrub than a fruit-bearing tree. You will often see groves of them growing together, because they can spread by underground roots. Their large, broad leaves (6 to 12 inches long) alternate along the branches and have a distinctive smell when they are rubbed or broken. (It reminds me of kerosene.)

It seems only a small fraction of the abundant small trees actually become large enough to bear fruit. They also fruit more when the trees that allowed them to thrive as shade-loving seedlings die and fall, leaving the pawpaws with more sun. Under the right conditions, they can bear quite a crop. Paw paws attract not only humans but are also a good food source for racoons, opossums, and squirrels. (As an added bonus, the leaves of the paw paw tree are the larval food of beautiful zebra swallowtail butterflies.)

For harvesting, you want the fruit to be quite soft; the best way to find ripe fruits is to shake the tree and go after the ones that fall down. The skin will be green even when ripe.

In the wild: We seem to find the most large, fruit bearing trees along the Potomac flood plain. Look for breaks in the tree canopy where pawpaws may be getting more sun. We've seen numerous fruits recently (not yet ripe) on trees in the Carderock area and at Scott's Run...and even a few in Rock Creek Park.

In your yard: Pawpaws were once cultivated by Native Americans, and Thomas Jefferson is said to have planted them at Monticello - so you'd be in good company if you want to try to grow one. They're supposed to be easy to start from seed. You might have the best luck with seed collected from racoon or opossum scat. However, that presages a challenge to getting the fruit from your trees -- the raccoons may beat you to them.

Like the photos in this post? Mouse over for credits; a click takes you to the photographer on Flickr.

LOOK FOR: Chicken of the Woods

Chicken of the woods is a great mushroom with a great name. The fungus forms overlapping orange fans that look a little like the tailfeathers of a chicken. And if you cook it and eat it (only after careful ID, please!) you may find the texture a lot like chicken, too.

Photo by the Natural Capital

Before the tree leaves start to change, there isn't much orange in the woods. So chicken of the woods (also known as sulfur shelf, or Laetiporus sulphureus, literally "bright-pored sulphur-yellow") can be eye-catching even from quite a distance. There are actually two varieties. One is bright orange on top, with bright sulphur-yellow underneath. It always grows on tree trunks (standing or fallen). The other is a paler orange on top, and nearly white on the underside. It often grows from tree roots. Both have tiny pores on the underside, rather than the gills you see on grocery store mushrooms.

Chicken of the woods is fairly difficult to confuse with other mushroom species once you know what you're looking for. Still, if you want to eat the mushrooms you find, we highly recommend a foray with the Mycological Association of Washington. If you can't make it out with the group, get yourself a couple of ID books to cross-check your identification. And, even once you're sure you've got the right fungus, start out by eating only a little bit and see how it sits with you. For a small percentage of people, chicken of the woods can cause stomach upset.

Photo credit: Matt Reinbold

In the wild: As the name suggests, look in the woods -- although we've seen a few specimens of the root-growing variety coming up in suburban yards, we've found far more of the tree-growing variety in the woods. If you find some, check back again next year in the same spot -- they can come back several years in a row.

In your yard: Although there are companies that sell mushroom kits, we haven't seen this species for sale yet. You'll just have to go for a walk in the woods!

LOOK FOR: Goldfinches

Goldfinches are one of the most brightly colored common birds in the DC area. If you saw one in a tropical area, you might be transfixed...but here, it's just a goldfinch. Well, stop and let yourself be transfixed anyway. They're lovely birds.

Male goldfinch by ehpien

It's the male goldfinch that's a showy yellow-and-black bird. The female is the same size and shape, but is much duller-colored. You'll often see them together in pairs (they're monogamous) or groups. During the winter, the males will molt and take on the duller colors of the female. They'll grow brighter feathers again in the spring in time for mating season, which is the real purpose of all that color, after all.

Unlike most birds, goldfinches rely almost entirely on seeds; they don't seek out insects for food at all. In fact, you could call them "thistle birds" -- the first part of the Latin name Carduelis tristis comes from Carduus, a genus of thistle found in Europe and Asia. (The species name, tristis, comes from the Latin for "sad," which makes no sense to me - anyone?)

Female goldfinch by sofafort

Around August, the goldfinches start to regularly come to our yard to eat the seeds of our summer flowers. Among the flowers we offer, they seem to be particularly attracted to anise hyssop, purple coneflower, oxeye sunflower, and black-eyed susan. In the spring it also brings in the goldfinches when we let the kale and cilantro go to seed in the vegetable garden. Other flowers reported as attractive include milkweed, asters, and sunflowers. They'll also feed on grasses and the seeds of trees, including alder, birch, western red cedar, and elm.

Besides looking for the distinctive yellow markings, you can learn to listen for the song of the goldfinch. This video has a good example:

In the wild: Look for meadows on edges of woods. Goldfinches will feed on the seeds of the sun-loving flowers in the meadow (where you'll be able to see them better), but nest in the trees and shrubs.

In your yard: You can purchase birdfeeders specially designed for goldfinches, and fill them with thistle or nyjer seed. Squirrels seem less interested in these tiny seeds than in a typical birdseed mix, but be careful -- those plants may start growing where you don't want them from spilled seed. Goldfinches will also eat sunflower seeds out of a more typical birdseed. Or, just plant yourself a goldfinch garden with some of the native flowers listed above.

LOOK FOR: Dragonflies

Why do we love dragonflies so? The iridescent grace of finely veined wings, the constant motion over a sunny pond, the bright colors and striking patterns...

Plus the eating of mosquitoes. As adults, dragonflies use their legs as a basket to catch other flying insects, like mosquitoes -- thus their nickname, "mosquito hawks."

But they don't just eat mosquitoes in the air. Both dragonflies and mosquitoes lay their eggs in water. And dragonfly nymphs are voracious eaters, with mosquito larvae on their menu. Some dragonfly nymphs also eat much larger prey, like small fish, tadpoles, and other aquatic critters.

When it's ready, a dragonfly nymph crawls out of the water, splits its back open, and emerges as an adult. Fast forward to 2:20 in this video to see the process, greatly sped up:

There have been at least 120 species of dragonfly recorded in DC and Maryland. Here are a few you might have noticed:

Common Green Darner Anax junius	Halloween pennant Celithemis eponina
Common Pondhawk Erythemis simplicicollis	Blue Dasher Pachydiplax longipennis
Autumn Meadowhawk Sympetrum vicinum	Common Whitetail Libellula lydia

In the wild: Look for a sunny pond or stream. You may notice that you see different species depending on the size of the body of water, whether it is moving or still water, and how shaded or sunny it is.

In your yard: You're much more likely to have dragonflies if you have water. This is our third summer having a pond in our backyard, and we have started to see dragonflies relatively regularly. Which makes me a very happy camper.

What's your favorite spot for watching dragonflies? Do you have a favorite species that I left out? Leave us a comment!

Photo credits: Top photo by the Natural Capital; Common green darner by mean and pinchy; Halloween pennant by afagen ; Common pondhawk by meanlouise; Blue dasher by Dope on the Slope; Autumn Meadowhawk by jerryoldenettel ; Common Whitetail by afagen. Click on any picture for a larger version of the photo on flickr.