Tuesday, May 10, 2011

Our NYC Weeds: part 2

The Weed Atlas compiled here is hardly complete. I'm including those weeds that I find in New York City -in yards, in the cracks of sidewalks, in parks, on piers. NYC enjoys most of the weeds common to eastern North America, so that if you find yourself here and the weed you are trying to identify is in, say Clearfield, PA or Springfield, IL, the atlas may still be of use to you. Many, if not all, of these weeds are endemic to the entire United States, but as you head west, to drier climates, there are additional weeds that are less common to the wetter Eastern Deciduous Forest.

Many of us get online now when we want to identify something, and that is no less true for the weeds in our yards. For years I depended on the book Northwest Weeds as my weed ID source because no proper book had been published for the Northeast. Today, that is no longer the case, so that some of what I publish here has been cross-referenced with the excellent Weeds of the Northeast by Uva, Neal, and DiTomaso.

Deciding what is a weed and what is not can be fool's errand. But for the sake of limits, I define weeds to be those plants that grow of their own accord in areas disturbed by the activities of humankind, and are regionally and often globally, ubiquitous. Some weeds can also be distinguished as invasive to a region, but the word invasive is often used to describe out of bounds garden plants as much as exotic plants in uncultivated regions. We tend to resist calling garlic mustard, for instance, a weed, and instead call it invasive. Why? Because it invades uncultivated locations more than, say, your garden or a farm field. What is true is that weeds go wherever we do; weeds define us as much as we define them.

The atlas follows in alphabetical order, with the botanical name first when I can accurately state it. All listings have at least one photo, which can often be clicked on for a larger image to help in identification. Each listing will also provide a link to another site with broader description and more photos to further your research. Some of the plants listed are noted as edible, but please don't eat anything unless you have positively identified and properly prepared it.

Finally, please note that this is a free service on the Web. I typically do not check to see if links are still working or broken because a page has gone 404. I do see your comments below, eventually, and you can check back for my response. You can also email me at nyc*garden*@*gmail (.com) without the asterisks and parenthesis used to deter bots.



Achillea millefolium, Common Yarrow, Milfoil, or Field Yarrow

Common Yarrow is a perennial plant often associated with old cultivated fields and sometimes lawns. If it is mowed, it can form mats of fine foliage close to the ground. Of course, field yarrow is related to the garden Yarrow, but its flowers are generally white, sometimes with a pinkish tinge, and its foliage is very finely cut. Garden Yarrow has been bred to have many colors and in some varieties, soft gray foliage. I grow both kinds in my garden, but beware, the field Yarrow spreads rampantly.


Ailanthus altissima, Tree of Heaven

Young tree, often found growing on fencelines and in pavement cracks.

Ailanthus will grow almost anywhere, roofs, windowsills, cracks in pavement. It has an extremely aggressive nature and is incredibly resistant to permanent removal. I once removed a concrete pad from a backyard in Brooklyn. Underneath this old concrete, hundreds of little ailanthus roots just waiting for the right opportunity. Can be taken out, but requires perseverance. Often confused with Sumac. Ailanthus will get much taller than sumac, in fact Ailanthus will be a tall tree in short time. The sumac has deep red, upright seed heads, the Ailanthus drooping pale yellow seed clusters.


Alliaria petiolata, Garlic Mustard

Garlic mustard.

I spied thousands of Alliaria petiolata or 'Garlic Mustard' plants and hundreds of Hesperis matronalis or 'Dame's Rocket' from a Metro North train window. I saw several good looking clumps of Garlic Mustard in Cadman Plaza Park this spring, where I pulled some leaves and crumpled them in my hands to catch the faint, slow release of garlic scent they're named for. Garlic Mustard is an edible invasive of woods, hedgerows, and fields -but primarily woodland settings. Known for crowding out spring ephemerals, they are often on forest and park manager lists for eradication.

Dame's rocket -also a mustard.

A relative of these is a cottage garden favorite, the cultivated Dame's Rocket, as seen here blooming alongside much more garlic mustard. I first became aware of the mustards when I lived in southern New Mexico -it was the plant growing along all the ditches in winter. Mustards tend to be cool weather biennials, and in our region that means you'll see then green up and flower in spring, but also remain green into autumn and be one of the earliest greens of spring. If you want to pull them, make sure to grab under the horizontal stem, just beneath the leaf litter, to get the whole root.


Amaranthus spp., Pigweed

Amaranth comes in many forms, some weeds, some culitvated for their leaves, roots, seeds or for ornamental uses. There is a woman who comes by late spring into summer pulling the amaranth from the fence line along the sidewalk to eat, I presume. There are several varieties of this plant and are easy to misidentify within the species. All have the telltale inflorescence, although with variations in length, bushiness and color. It is an annual plant that tolerates dry conditions. Pull it up early and don't let it go to seed as the thousands of seeds per plant can last up to thirty years in the soil.

Amaranth gone to seed.


Ambrosia artemisiifolia, Common Ragweed

Common Ragweed. Too many people think that this is not the culprit for their allergies, yet it is. Flowering at the same time as Goldenrod, showy Goldenrod often gets the blame. Even allergy pill commercials seem to show yellow flowering plants in their scenes.

Ambrosia is a mystery to me, but artemisiifolia refers to the leaf structure which is similar to many Artemesia plants like mugwort found one entry below this one. To some the foliage looks similar to that of French marigold, a plant whose origin is really Mexico despite its name.

The stems of Ragweed are reddish and highly pubescent -meaning that there is hair present.

Ragweed flowering stems shoot straight up, sometimes leaning over. From above they look mostly green with hard to see flowers.

How do you know that Ragweed is responsible for your allergies? The flowers all face the ground. Flowers that face the ground are less likely to attract pollen-spreading insects like bees and flies. Flowers that are bright and yellow, facing outward like Goldenrod are insect pollinated. Ground-facing flowers depend on the swaying and shaking caused by the wind. This same wind picks up the pollen as it drops out of the flower, spreading it several feet or yards or miles. Ragweed is wind pollinated, and that, my friends, is something to sneeze at.


Artemisia vulgaris, Mugwort

Artemisia vulgaris is the weed of a NYC metropolitan life. This is the plant that greens brownfields, empty lots, roadsides, sidewalk cracks, chain-link fence rows, and overpass embankments. One summer along the waterfront in Williamsburg, I witnessed thousands upon thousands of lady bugs crawling over a practical monoculture of mugwort. All that red and green, quite amazing.

Some people confuse this plant's young growth with common Chrysanthemum. Please don't. The underside of Mugwort's leaves are fuzzy and light gray, and its foliage highly aromatic, where as the chrysanthemum not as much. The leaves become thinner and elongated as the plant matures and its flowers are inconspicuous. Mugwort is perennial and spreads via vigorous rhizomes -so pull, pull, pull or enjoy the greenery. I have noticed one sidewalk garden in Red Hook that seems to have struck a fine balance between their perennials and the mugwort, but this is not the norm.

At flowering maturity, mugwort will take on this appearance -rangy with small lanceolate leaves, and small greenish-yellowish-white flowers.

Mugwort flowers up close.


Asclepias syriaca, Common Milkweed

Milkweed jumps out thanks to its broad, fleshy leaves with pubescent undersides, mass of flowers, and erect habit in fields and meadows. A native to North America east of the Rockies, it is only considered a weed in disturbed areas like old farm fields by crabby old farmers. It likes sandy soil, tolerates acidic soils, but grows most anywhere there is enough sun and moisture.

The leaves have a light gray pubescence on the underside. There may be a reddish tinge to the central leaf vein.

Asclepias syriaca exudes a milky sap when any part is torn and is a favorite of the Monarch Butterfly in its larval stage. Milkweed is known to produce useful fibers, and its young shoots, buds, and flowers are edible when cooked. But do not confuse it with the Dogbanes, which look very similar if you are not looking closely (see next image).

Apocynum cannabinum, Indian Hemp or Hemp Dogbane. Notice its reddish stems and different flowering character. Indian Hemp will produce a milky sap just like Milkweed.


Celastrus orbiculatus, Oriental Bittersweet

In summer the vine is green with small cream-colored spots. In autumn, the vine hardens and darkens.

Late autumn berries, commonly used for wreaths.

Oriental Bittersweet, native to eastern Asia, loves fence rows. I first came across this vine on the stockade type fence around our backyard and you'll probably find it on chain links just like the one above. The berries hang on long and are a favorite of birds, so despite their good looks, if you want it gone, get it before it sets fruit. Just make sure it's not the native variety, American Bittersweet, Celastrus scandens. The decorative possibilities of the vine in late autumn are well known, but selling it live or cut is illegal in some states. No wonder it is 'bittersweet.'


Chenopodium album, Lamb's Quarters, also Pigweed

Mature plant, streetside.

The 'goosefoot' name refers to its leaf shape.

Chenopodium (the name: cheno-goose, podium-foot describes the leaf shape) is commonly known as Lamb's Quarters. Some call it Pigweed, confusing it with the Amaranthus species. The common name may hold water however, it seems taxonomists may be changing the Chenopodiaceae classification to Amaranthaceae. This weed grows everywhere in the city and is a common weed from my childhood yard. Drought, sandy soil, and compacted earth are favorite locations for this plant. It can stay compact and bushy, yet sometimes is open and willowy . Young leaves are eaten in salads or cooked and some make a meal out of the seeds -in this way it is similar to amaranth. I like it for its intense magenta leaves often found half way up the plant.

Mature lamb's quarters with magenta leaves at its base.

Fruit in later summer.

Magenta fruit in autumn.


Cynanchum nigrum, Swallowwort

This one's called Swallowwort, cause it'll swallow anything in its path.

The fascinating flower, not quite black, more dark plum colored.


Commelina communis, Asiatic Dayflower

The Commelina species here is the non-native, asiatic variety. There are a few tell-tale traits to divine the two. In NYC, you probably have Commelina communis. It's called Dayflower because the flowers are with us only for a day. Its quite a beauty and I let it be in corners of the garden. It spreads but Dayflower is easy to pull.

Dayflower with a common garden companion, Smartweed.


Draba verna, Early Whitlow Grass

This annual weed from Eurasia is a cool season mustard. It flowers quite early as long as there is sunshine. It tends to grow in sandy areas, open fields, poor lawns, and other disturbed sites.

Look for the notched petals and leafless stalks of Early Whitlow Grass, which is not a grass, but a mustard. There are perennial Whitlow Grasses, but these do not have the notched petals.


Erigeron annuus, Annual Fleabane

This specimen sprouted in early spring in my Brooklyn garden and began blooming in mid-May. Fleabane is native to most of the Eastern Deciduous Forest, and belongs to the great family of Asteraceae. Here we have a case of the native "weed." It had a pleasing form before flowering, which led me to be unsure if I had planted a perennial and forgotten. So I left it to flower and discover what it was.

At flowering, the lower leaves yellowed and stems became leggy. In a garden, this would work well where other plants hid the lower leaves.

Pretty, pinkish-white daisy-type flowers. Is it the bane of fleas? I hope I'll never know.


Fallopia japonica, Japanese Knotweed

Attractive plants make successful weeds.

The heart shaped leaves on young red stems give it away.

Don't let those quaint and attractive leaves of the young Japanese Knotweed fool you -the bottom photo shows how large these can get when not attended to. An attractive herbaceous perennial, it escaped garden cultivation years ago to become a major weed of wetlands, roadsides and yards. The specimen above grows in a fence row in a Brooklyn neighborhood, and has sent its rhizomes under the concrete sidewalk to the adjacent strip where it grows a similar height each year. Persistent, one must continually remove rhizomes, roots and stems. The young shoots are edible, making spring pulling more tolerable.


Hedera helix, English Ivy

English ivy scrambling up trees and across the ground in Prospect Park.

Hedera helix may not be a weed to many, and I don't always consider it a weed myself. But this plant does escape and does get out of control (the Pacific Northwest comes to mind where I saw it clibing trees in Forest Park in Portland, Oregon). I think we may have all seen at least one tree with this plant growing all over it. For the many who have dry, shady spots in front of or behind their homes, this has been the answer to concrete or mulch. However, there are many different varieties - so choose one that is attractive and less invasive to woodlands. To remove, simply pull it up. It roots from cuttings of the vine, so remember to pick up the pieces.


Lamium purpureum, Purple Dead Nettle

Purple Dead Nettle is common in fallow fields, disturbed areas, and even lawns. This specimen was found in a New York City community garden plot in late March, having sprouted after the plot laid fallow over winter. It's similar to garden Lamium and a quick spreading ground cover.

Its flowers are attractive to bees because it blooms profusely and early, when little else does. You'll often find Purple Dead Nettle blooming near a common look-alike, Henbit.


Lamium amplexicaule, Henbit

Henbit will bloom during cool weather, just like its cousin, Dead Nettle, and you'll often find them side by side, possibly confusing them because of their purple flowers. Henbit has a tap root, so pull when the soil is wet for greater effectiveness. Apparently the name Henbit reveals how chickens like to snack on some part of the plant, and some say it is an edible spring green for folks not too chicken to eat it.


Linaria vulgaris, Butter and Eggs

This nice specimen of Linaria vulgaris was found on a fence line at the sidewalk's edge in Red Hook, Brooklyn. Likes well drained soil, so I suppose an old, demolished building's site will do. Butter and eggs refers to the coloring of the flowers, but this weed has dozens of colloquial names and a sentimental following.


Malva neglecta, Common Mallow

Malva neglecta is a common roadside, lawn, and garden plant. It belongs to the large family of Mallows that includes Hollyhocks, Swamp Rose, even cotton. Some call Common Mallow by the name "cheeses" due to its round cheese-wheel like fruit. The flowers range from white to pink to purple and are often quite attractive, no doubt contributing to mallows' success. To pull it, you should soak the ground first as it has a tough taproot. Apparently it has edible leaves and roots and a long association with humans.

Mallow patch.

Mallow flower.


Oxalis stricta, Yellow Wood Sorrel

Yellow Wood Sorrel is one of those North American natives that is also native to Europe and Asia. It's therefore ubiquitous and most often considered a weed. It's often confused with, or called, clover because of its trifoliate leaves. Although considered edible, also consider that most Oxalis species have oxalic acids which in quantity prove harmful.


Phytolacca americana, Pokeweed, Pokeberry or Poke

Pokeweed bush.

Phytolacca americana is native to the North American continent. As a kid, I used to let the pokeweed grow tall in our backyard and then harvest the stalk, drying it in the sun for a week. Afterwards, I made spears with the woody, straight stalks. Us kids also made "wine" and dye with the berries. We never drank that wine, fortunately, as we intuited this was a bad idea. And of course, it is a bad idea because all of this plant is poisonous. However, it is common to boil the young greens in the American South. You may still be able to buy cans of it down there.

Pokeweed in a can.

Poke berries are loved by many birds -it is not poisonous to them. While this plant is perennial, it also propagates via seeds dropping from all those happy birds. Pull to remove from the garden, but leave some in the wild parts for the birds. I find pokeweed to be attractive, but contributing to that may be a bit of nostalgia.

Pokeweed leaves, berries and rose-colored stems.


Plantago lanceolata, English, Ribwort, or Narrowleaf Plantain

Basal rosette.

Above, is a mature, flowering specimen in a poorly kept "lawn." It likes full sun to part shade. You are likely to find this in poor soils, fields, road edges, and weedy lawns. Plantains are known to do well in compacted soils.



Plantago major, Common Plantain, Broadleaf Plantain

Single plantain with seed stalk.

A patch of plantain.

Plantago major is one of the most common weeds of roadsides, lawns, and pathways. This plant will grow in wet or dry, highly compacted soil, areas little else can. There are native species of this plant in the area, but if it's in your lawn, it is likely to be this one. Best method for eradication is to pull it after a good soaking rain and keep your soil aerated. Otherwise, you'll just have to live with it, because these are tough.


Persicaria pennsylvanica, Pennsylvania Smartweed

There are several native and non-native forms of what was until recently called the Polygonum family and is now Persicaria. Smartweed is an excellent place to begin your weed identification journey as there are overlapping traits among the native and non native varieties, making it a challenge to your observational skills, and the names seem to keep shifting. As I stated in Our Weeds, part 1, I often leave this weed in the garden for its ability to fill blanks with its attractive foliage and pink flowers. It self-sows abundantly so that there is never a shortage of plants. The young plants are distinctive and easy to pull.

A good sized patch of Smartweed.

It can be a nice garden plant. As a species, Smartweeds are successful across a broad range of soil types, light conditions and zones. I've seen them growing in ponds, at the edges of ponds, prostrate in lawns, in sidewalk cracks, and more.


Rumex acetosella, Red Sorrel or Sheep Sorrel

I think Red Sorrel is really good-looking in a field of grass, where it is likely you'll find it. It is also found on other disturbed areas like roadsides or brownfields. It tolerates poor drainage and acid soils. If you have it, dealing with those conditions may be part of the mitigation process. Apparently it has a strong sour taste and has been known to be fatal to sheep.

Red Sorrel.

Red Sorrel flowers can also be yellow.


Rumex crispus, Curly Dock

This stand of Curly Dock has been getting stronger by the year. I think we lose neighbors to it. It may eat people.

Aphids enjoying the succulent stems of Curly Dock.


Silene latifolia (alba), White Campion

White Campion is an attractive, flowering weed of pastures, meadows, and other weed-filled places. Maybe you don't want to pull it, but if you do, it has a tap root. Wet the soil thoroughly first to make the pulling easier.


Tragopogon dubius, Western Salsify

You might think Western Salsify is a giant dandelion. Common throughout the American West, it is making inroads into the drier parts of the eastern states. Hard to get much more east than Long Island, NY, where this one was growing along a fence line near the shore.

Dandelion-like seed head can be up to 6 inches across.


Trifolium repens, White Clover

Trifolium repens is a part of the Pea family of plants, and one of many Trifolium (clover) species including Red Clover and Hop Clover. If you do a web search of the word clover you'll get equal parts how to kill it in your lawn and how to grow it in your lawn. Either way you have it, clover is an introduced species commonly used as forage for livestock and honey production. White Clover is a perennial, spreading over ground and rooting at its stem nodes.

A community of white clover.


Trifolium pratense, Red Clover

Red Clover is much like the white clover, but more upright and typically larger. It is often found in old farm fields. pastures, and roadsides.


Veronica persica, Persian Speedwell, Birdseye Speedwell.

I found this specimen of Persian Veronica in an athletic field in Red Hook, growing at a bland time of the year, maybe late March. I yanked it up and planted it in a barren spot underneath a rose. Now it cannot be stopped, but is easy to pull should it go too far.

It spreads along the ground, self seeding along the way. Blooms early and is visited by some bees and flies. Birdseye Speedwell may not tolerate mowing if you have this and want to get rid of it. Clearly I didn't mind it so much that I transplanted it to the garden.

Bluish, small flower.


No comments:

Post a Comment

If I do not respond to your comment right away, it is only because I am busy pulling out buckthorn, creeping charlie, and garlic mustard...