Botany Blog Plants of the Northeastern U.S.

January 28, 2013

Don’t trust everything you read on Wikipedia

Filed under: Naturalized Plants — admin @ 22:24

So I was a little bored this evening and decided to do a little reading on the flora of Madagascar. One of the interesting things I learned is that the Didiereaceae is a family of spiny plants found in Madagascar. The family has been considered endemic to the island, but recent molecular evidence suggests that it should include the genus Portulacaria, which would expand the range of the family beyond the island of Madagascar.

That much seems to be accurate. What really caught my attention was a mysterious claim on Wikipedia that the common purslane (Portulaca oleracea L.) was now being called Portulacaria oleracea. Well that is significant since we would then have a new family represented in NY State. The problem is that the Wiki article does not give an authority for this name. It gives an authority for the other species of Portulacaria. This is important, because if there is no authority then one would conclude that there is no published rationale for giving this species a new name or placing it in a new family! You won’t find this name in Index Kewensis, but you can find references to the name on other web pages. I would suspect the authors of those web pages got their information from Wikipedia. And that’s why you shouldn’t trust everything you read on Wikipedia.

August 13, 2012

Buffalobur Nightshade

Filed under: Naturalized Plants,North American Native Plants — admin @ 19:44

Buffalobur Nightshade (Solanum rostratum) is a member of the nightshade family (Solanaceae) that is native to the Great Plains. It has been introduced, presumably accidentally, well outside its native range. The plants shown here were recently found in Onondaga County, NY. It is a somewhat attractive plant in flower but the stems and calyces are covered in stiff spines. Plants have a spreading habit.

Buffalobur Nighshade habit

Flowers have yellow petals and 5 stamens; 4 stamens are of equal length and the fifth elongate and curved

Solanum rostratum flowers

The fruit is a berry that remains enclosed in the calyx which is beset with vicious spines

Solanum rostratum fruit

The leaves are deeply pinnately lobed. This species is in the same genus as potato and is vulnerable to damage from the same insects.

Solanum rostratum leaf

 

April 6, 2012

Viola odorata

Filed under: Naturalized Plants — admin @ 22:24

I was searching Google images the other day for a good picture of the flowers of Sweet Violet (Viola odorata) and could not find one, so I took a few pictures using a hand lens today.

Sweet Violet

 Although we have a number of native violets, this species was introduced from Europe and is commonly found in lawns. It has leaves and flowers arising directly from slender stolons (runners) rather than leafy upright stems. The flowers can be white to purple. A feature that distinguishes it from similar violets is a downward curved hook at the end of the style.

Sweet Violet

March 17, 2012

Plants blooming now

Filed under: Naturalized Plants,North American Native Plants — admin @ 14:57

With the exceptionally warm weather we are experiencing now in the northeast, I decided to take a trip to Little York to see if any plants were blooming. While the spring ephemerals are still at least a few weeks from flowering I did find Daphne and Speckled Alder in full bloom.

Speckled Alder

Speckled Alder

The male flowers are in the larger catkins, while the female flowers are in the short reddish ones. Daphne has more showy blooms, with 4 magenta petal-like sepals and a light fragrance. While the speckled alder is a native wetland shrub, Daphne mezereum is native to Europe and parts of Asia. It can be found in some of our rich woodlands, often along trails. The flowers are followed by bright red fruit in May or June.

February Daphne

Not much else was flowering, however the maples and aspens appear to be flowering on the hillsides a few weeks earlier than I’ve seen in previous years.

March 11, 2012

European Frog-bit

Filed under: Naturalized Plants — admin @ 12:32

The European frog-bit (Hydrocharis morsus-ranae) is thought to have been first introduced to St. Lawrence County in New York in 1974. The distribution map from the NY Flora Atlas (below) shows the counties where specimens have been collected.

Frog-bit range in New York

This map does not appear to reflect the current distribution of this species. I have observed it at Raquette Lake in Hamilton County and at Three Rivers in Onondaga County. It likely spread to the latter area from Oneida Lake via the Oneida River. This species looks like a tiny water lily with 3 white petals. It might be confused with the native Nymphoides cordata, which has 5 petals.

Common Frog-bit

European Frog-bit

There is an American frog-bit (Limnolobium spongia) that is native further south of New York and is occasionally introduced. It differs from the European frog-bit in having branched (rather than unbranched) roots, petals less than 1.5 times as long as the sepals (rather than more than 1.5 times as long), and one stipule per leaf that is attached below the petiole (rather than 2 free stipules).

December 12, 2011

Epazote

Filed under: Naturalized Plants — admin @ 01:56

The plant known as epazote or Mexican tea (Dysphania ambrosioides) is naturalized in the eastern United States as a weed in gardens, on roadsides, and in waste places. It is a pungent herb that has traditionally been used as a flavoring for black beans and is reputed to have carminative and anti-parasitic properties. Until recently most authorities called this plant Chenopodium ambrosioides. However the genus Dysphania, which was originally applied to a small number of Australian species, has been expanded to include species of Chenopodium with glandular trichomes (Mosyakin & Clemants 2002).

The essential oil of the plant consists mostly of the bicyclic monoterpene ascaridole. The name is likely derived from the genus of parasitic nematodes Ascaris. It is reputed to be explosive when heated or treated with organic acids. The chemical structure of ascaridole seems to hint at the hazardous potential of this compound.

ascaridole

source: Wikipedia

Literature Cited

Mosyakin, S.L. and S.E. Clemants. 2002. New nomenclatural combinations in Dysphania R. Br. (Chenopodiaceae): taxa occurring in North America. Ukrayins’k. Bot. Zhurn. (Ukr. Bot. J.) 59:380–385.

August 4, 2011

Nepalese Smartweed

Filed under: Naturalized Plants — admin @ 22:49

Was at Lime Hollow a few weeks ago and came across an unfamiliar smartweed growing next to a gravel path. This one had winged petioles, something I don’t usually associate with plants in the genus Polygonum. I snapped a picture hoping I could figure out the species based on this feature

Polygonum nepalense leaves

But no luck figure this one out…until a few days ago I was out at Kettle Bail State Forest and found what appeared to be the same plant growing along the edge of a truck trail. This one had flowers on it and I was able to key it out – Polygonum napalense, or Napalese Smartweed, is a native of China known only from Sullivan, Delaware, and Otsego counties in NY. Assuming I have the identify correct on this one it is now known from multiple locations in Cortland County, .

Nepalese smartweed habit

Napalese smartweed flowers

March 16, 2011

Early Spring Flowers

Filed under: Naturalized Plants,North American Native Plants — admin @ 23:51

Spring begins in only a few days, and while the showier spring ephemerals won’t be up for at least a month there should be some buds breaking in the coming weeks. Skunk cabbage is already blooming in some places, and soon some of the following should be emerging.

Coltsfoot (Tussilago farfara) sends up its dandelion-like flowers before its leaves. It is a native of Europe and Asia and has naturalized throughout North America. It has been used medicinally as a cough-suppressant but there now evidence that a chemical constituent of the plant is a powerful mutagen. It is typically found in disturbed areas.

Coltsfoot

In wetlands one may find Sweetgale (Myrica gale) blooming in early April.  This plant associates with nitrogen-fixing bacteria and the crushed leaves smell much like bay leaves. It is in the same family as Bayberry (Morella pensylvanica), which has fragrant berries that have been used to make candles.

Sweetgale

In moist woods of Central New York one can find Spicebush (Lindera benzoin), a shrub with fragrant leaves and orange or red berries that ripen in the fall. The floral effect of Spicebush is reminiscent of Forsythia but not quite as showy. It is the larval food plant of the spicebush swallowtail.

Spicebush

July 18, 2010

Bittersweet Nightshade

Filed under: Naturalized Plants,Uncategorized — admin @ 19:12

Bittersweet Nightshade (Solanum dulcamara) is an herbaceous vine in the potato family (Solanaceae). It is native to Eurasia but has naturalized widely in North America. It occurs in a variety of habitats provided sufficient light is available. Several features aid in identification. First are the purple flowers with five reflexed petals and bright yellow stamens

Bittersweet Nightshade Flowers

The fruit matures from green to yellow, orange, and finally bright red and resembles a small tomato (also in the potato family). The plant gets its name from the reputed taste of the fruit, which is said to be bitter at first but later sweet. While the fruits are said to be less poisonous than the rest of the plant, I have never dared to taste one as all parts of the plant contain solanine which is extremely toxic. While poisonings are rare, fatalities have been known to occur.

Bittersweet Nightshade Fruit

The leaves are somewhat arrow-shaped and often have two or more lobes at the base. The color is dark green and they seldom have evidence of herbivory. The smell of the leaves is perhaps this plant’s most distinguishing characteristic, similar to tomato but much more foul and disagreeable. This trait has come in handy when it has been necessary to identify seedlings in the field.

Bittersweet Nightshade Leaves

June 27, 2010

Poison Hemlock

Filed under: Naturalized Plants,Uncategorized — admin @ 19:40

Poison hemlock (Conium maculatum) is a biennial herb that can grow to 3 m tall. It has a smooth stem that is often purple-streaked or spotted. The leaves are broadly triangular and divided into 3-4 segments with finely divided leaflets.

Poison Hemlock Leaves

The white flowers are produced in umbels up to 6 cm wide and rather resemble a large Wild Carrot (Daucus carota).

Closeup of Poison Hemlock Flowers

This species is native to Eurasia but has been introduced and has spread widely throughout North America. Most often found in partially shaded, disturbed areas on soil ranging from dry to wet, it is perhaps best known as the plant given to Socrates after he was sentenced to death. All parts are extremely poisonous but the parts of the plant that are most toxic are the seeds and root.

Poison Hemlock Flowers

 

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