365 Urban Species. #223: Goldenrod. #224: Ragweed.

[urbpan]

A stalk of goldenrod colonizes a roadside planting in the Longwood Hospital area in Boston.


Ragweed by cottonmanifesto. A sidewalk crack near the same location.

Urban species #223: Goldenrod Solidago canadensis
Urban species #224: Ragweed Ambrosia artemisiifolia

Ragweed and goldenrod are often discussed together. These two plants, both common in urban, suburban and countryside contexts, bloom at around the same time toward the end of the summer. Goldenrod (any of more than a hundred species commonly found in North America) produces showy plumes or crowns of tiny yellow flowers. Often it colonizes a field or lot and turns the whole area into a bright wash of color. When I was growing up, any time anyone sneezed in late summer, some parent blamed the goldenrod. The ubiquitous weed was an obvious scapegoat--doubtless that all that yellow must be producing huge amounts of irritating pollen. Of course, the goldenrod's color is intended to attract insects to mechanically transport the pollen from one place to another, and relatively little goldenrod pollen should be drifting on the air (though it can cause human, and canine, allergy suffering). Instead we can blame those plants with flowers with no attractants for insects--no strong odor or bright color. We can point to many kinds of grasses, and then those weeds with green flowers: mugwort, lambsquarters, and of course, ragweed.

Ragweed is considered the worst allergy-producing pollen. Along with its pollen's virulence, we also must cope with the plant's abundance. Ragweed grows well in the city, in poor soil compacted by foot traffic. It's seeds are high-quality food for birds, notably seed-eating urban species such as rock pigeons and house sparrows, who will spread the plant far and wide.

Native Americans used a tea of ragweed roots to alleviate menstrual pain, and rubbed ragweed on their skin to treat insect bites. As ragweed is known to cause contact dermatitis, one can speculate on its affect on skin already irritated by a mosquito bite. The pollen of at least one species of ragweed (Giant ragweed A. trifida) is harvested to make anti-allergy medication.

Goldenrod also has a history of human association. Reportedly it was used to help heal wounds (resulting in the Genus name: Solidago, to make whole or solid) by the Crusaders. Also, when folks in Boston were angry about a certain tax on imported tea, they made "liberty tea" from goldenrod. I'm frankly skeptical about this last use, as goldenrod is one of the only plants uneaten in the deer enclosure that I maintain at work--and those deer eat poison ivy and garlic mustard. In addition to tea, apparently the blossoms can be fried, like dandelion flowers are, into fritters.

Along with the insects that pollenate them, there are many species of insects that use goldenrod as a kind of nursery. There are spittle bugs, hiding in protective froth attached to the stems, and then there are several kinds of insects that inhabit the stalks themselves, causing the growth of goldenrod galls. Some birds, such as downy woodpeckers and black-capped chickadees are attracted to goldenrod fields, in order to feed on the larvae inside their galls.



This ragweed growing in a flowerpot outside of North Station in Boston demonstrates the plant's ability to spread and appear in unexpected places. Photo by urbpan.


Goldenrod by cottonmanifesto. Location: Parkway Road, Brookline. A rare single stalk, of a plant that forms thick stands. (This, and remaining photos by cottonmanifesto.)


A close-up of ragweed, showing the stalk on which the flowers, and then the fruit, appear.


A close-up showing the many tiny flowers that make up the goldenrod blossom.


This sidewalk tree planting in Brookline is entirely surrounded by ragweed.

Comments

[kryptyd.livejournal.com]

I wouldn't be so sure about people not drinking goldenrod tea because of it's horribleness! I used to work in a health food shop and have done (and continue) to take the most vile herbal remedies and teas (bilberry - yuk! aesculus - BLEYAAARG!)

[nutmeg.livejournal.com]

In case you were curious, in my research experiment, Ragweed had more insects on it than any of the other 11 species of plants I collected.

It is quite attractive to the herbivores!

goldenrod as an ecological marker

[lucubr8r.livejournal.com]

In the natural progression from meadow to forest (and after many years and trees die, back to meadow), I believe goldenrod is one of the last flowers to populate a meadow, and heralds the transition to woody shrubs and trees. As fascinating a plant as it is, its ubiquity always gives me pause to consider our paucity of native meadows and the human footprint on the environment.

[derekdicaprio.livejournal.com]

I think just its name is one of the most vile things on this planet. Ragweed? It's just ugly.

[urbpan.livejournal.com]

I almost wrote about that--one is Rags, one is Golden. They're simply descriptive names, but they are pretty revealing, at least as far as how people feel about them.

Giant Ragweed

[(Anonymous)]

I just got a new dog from a shelter. She eats Giant Ragweed everyday. I've been researching it to find out why, but haven't gotten a clear cut answer yet.

[(Anonymous)]

I have been growing a veggie garden for about a year. My wife planted marigold seeds, because she heard that it helps prevent insects in the garden. One day out of the blue (what I thought was a marigold, now knowing it was ragweed...duh) began to grow through out the garden. What an idiot....

[urbpan.livejournal.com]

Iirc, the foliage is similar.