Time to pull the mustard

Garlic mustard (Alliaria petiolata), that is. This exotic wildflower, introduced to the U.S. from Europe in the late 1800s, is killing our woodlands.

From the New York Times, May 2, 2006:

Researchers have found that it disrupts a healthy relationship between hardwood tree seedlings and soil fungi, with results that can be disastrous for a forest.

Many plants make use of arbuscular mycorrhizal fungi, which form an elaborate network of filaments throughout the soil. These fungi are a diverse group, but they all have one thing in common: they help plants take up nutrients from the soil, getting carbon in return.

Garlic mustard is a member of the mustard family, "one of the very few families that do not need to associate with mycorrhizal fungi at all," Dr. Stinson said. These species produce chemicals that have antifungal properties. Native mustards have been around long enough, she suggested, that the mycorrhizal fungi have learned to live with them. But the fungi haven't had time to adapt to garlic mustard. "It basically is killing off the fungi," she said.

It bullies out our native spring ephemerals, it secretes a compound which destroys the soil fungi that is critical to the survival of our trees, and it fools a native butterfly to lay eggs on it that its the caterpillars can't eat. Here's a primer on the proper protocols for pulling it out. It's a prolific seeder, so bagging it is important.

Freaky ramps

Today I was back at Corson's Brook Woods in Staten Island for my Torrey plant walk. I came across this: Ramps (Allium tricoccum) with a spooky white stripe. Prematurely grey from worry over site development? The state did want to build on the site. It's actually probably from a virus. I know some plants in the horticultural trade, such as tulips, have viruses introduced to created patterns on petals or leaves.


Gratuitous wildflower photo of downy yellow violet (Viola pubescens).

Sourland Mountains, NJ

All this rain is ruining my plant walks! I've been looking forward to the Raritain River floodplain walk on Torrey Botanical Society's field trip page. Bluebells, bluebells, and bluebells. They are really just gorgeous. And, for some reason, not in New York. So, I would've gotten my fix if it hadn't rained. And I hadn't gotten lost. Instead, I went to Sourland Mountain Nature Preserve.

Early saxifrage (Saxifraga virginiensis) on a muddy lump. Note the hairy stems. These sticky stalks protect its precious nectar and pollen from maurading non-pollinators such as ants.

Pennywort (Obolaria virginica) is an interesting wildflower with its reduced, scale-like leaves. This species is no longer found in NYC.

Emerging rattlesnake fern (Botrychium virginianum). A persnickety fern, a good indicator of ecological integrity, due to its relationship with mycorrhizal fungi. This species is rare in NYC.
Wild licorice leaves (Galium circaezans)

Jack in the pulpit (Arisaema triphyllum) with deep burgundy stripes on spathe, which acts as an umbrella for the spadix, the actual inflorescence hiding inside which bears tiny blossoms.

Corson's Brook Woods 07

Last year was my first time at Corson's Brook Woods, and it made a big impression on me - such a mecca of spring wildflowers! So, I visited again this year and it did not disappoint.

Blue cohosh (Caulophyllum thalictroides). A striking spring ephemeral, with its unusual flower color and greyish blue glaucous stem. Rare in NYC.

American beech (Fagus grandifolia). I don't know why, but beech trees hold onto their leaves all winter. They are a welcome splash of color in a winter woodland - and even in spring. Rich forest soils.


Bloodroot (Sanguinaria canadensis). Pure white. Lovely and fleeting. Rare in NYC.

Trout lily (Erythronium americanum). An impressive amount, it just went on and on. These types of shade tolerant species are slow growing, and so such large colonies are very old - the population could've been many decades old.


Virginia waterleaf (Hydrophyllum virginianum). Decorative foliage - the silvery spots that look like water stains. I'm surprised this isn't used more in the hort trade. It's a great groundcover. Found in rich forest soils and floodplains. Rare in NYC.

Interactive Key to Wetland Monocots

What a nifty new resource!

There is a new Interactive Key to Wetland Monocots of the US (ca. 2400
taxa) available from PLANTS (plants.usda.gov). See
(http://npdc.usda.gov/technical/plantid_wetland_mono.html) for details.
It is free for use and download and requires no installation or
registration.

The data set was developed cooperatively by the Missouri Botanical
Garden and the USDA NRCS National Plant Data Center and was compiled
from numerous and varied sources by Dr. David Bogler of the Missouri
Botanical Garden (ca. 1.7 million data points). The automated plant key
runs in a new version of SLIKS (www.stingersplace.com/SLIKS) which is
free and requires no installation. It lets you identify the monocots
known to occur in U.S. wetlands. The species list in this key is
derived from the U.S. Fish and Wildlife Service National Wetland
Inventory National List of Vascular Plant Species That Occur in
Wetlands: 1998 National List.

Herbaria aid climate change research

Haven't we been telling you that herbarium sheets are the foundation of all that is good and pure in the world? What is an herbarium sheet, you say? See this (then click on "store").



An old photograph shows that on Memorial Day, 1868, the deciduous trees in Lowell Cemetery in Massachusetts had yet to leaf out. On Memorial Day, 2005, they stood in full verdure. Leafing or flowering dates each year depend on temperature, and global warming has been driving those events earlier in many places. Plants take part in many ecological interactions—with their pollinators, for instance—that are precisely timed. Changes in their seasonal development may therefore bring on broader ecological disruptions. Records of past plant development are scarce, though, so analyzing trends in timing has been difficult.




Now Abraham J. Miller-Rushing and Richard B. Primack, both ecologists at Boston University et al. have compared dated historical photographs, as well as dated herbarium specimens, of plants in flower in eastern Massachusetts, with recent observations of the same species. The plants now flower about eleven days earlier than they did a hundred years ago, when the region was 4.5 Fahrenheit degrees cooler. Their findings echo independent estimates from other data, confirming that old photographs and herbarium specimens are reliable sources for climate-change research. (American Journal of Botany, in press, 2006)

Pollination Station

Lots of news about pollinators.

First, the bad news...
Long-term population trends for some North American pollinators -- bees, birds, bats, and other animals and insects that spread pollen so plant fertilization can occur -- are "demonstrably downward," says a new report from the National Research Council. However, there is little or no population data for many pollinators, which prompted the committee that wrote the report to call for stepped-up efforts to monitor these creatures and improve understanding of their basic ecology. Read more

Now, the good news...
U.S. Postal Service announced the creation of Pollination stamps which will be released next summer to coincide with National Pollinator Week (June 24-30). The stamps consist of four images arranged in two alternate and interlocking patterns. The intricate design of these beautiful stamps emphasizes the ecological relationship between pollinators and plants and suggests the biodiversity necessary to ensure the viability of that relationship.

Depicted on the Pollination stamps are four wildflowers and four pollinators. Two Morrison’s bumble bees are paired with purple or chaparral nightshade (one of the bees is actively engaged in buzz pollination). A calliope hummingbird sips from a hummingbird trumpet blossom. A lesser long-nosed bat prepares to “dive” into a saguaro flower. And a Southern dogface butterfly visits prairie or common ironweed.

And some interesting news...

Researchers Find that Flower Choice Matters

Rebecca Flanagan has probably come as close as a human can to reading the mind of a bumblebee.

Flanagan is studying the behaviors of bees as they gather pollen -- which plant species the bees forage on, which flowers they probe
and in what order, and how many blooms they visit before moving on to another plant.

But why go to such lengths to map the flight of the bumblebee? The bees are pivotal players in determining which plant populations survive through successful reproduction. If scientists could better understand nature’s decision-making process, then they could use the information to increase crop yields and to boost conservation of native plant communities.


For more information on pollinators: www.pollinator.org.

Natives for Invasives

This is a great new publication - there are lots of natives I hadn't thought of using in a horticultural situation. I do have a suggestion for improvement, however. There should be some kind of warning regarding use of Celastrus americana where people need to make sure these plants are purchased from a trustworthy source and labelled properly. Their exotic breathren are very similar and so hard to differentiate - especially the M. rubra. It's for exactly that reason that I tend not to recommend them to the average native plant gardener. That said...
Native Alternatives to Invasive Plants is an indispensable guide for everyone who loves dazzling gardens and cares about the health of North America's natural landscapes. Invasive plants, the overwhelming majority of which are not regionally native, brazenly spread unchecked across residential landscapes, parks, preserves, roadsides, and other wild lands, supplanting native species and ultimately threatening the ancient biological communities in their path. In fact, most scientists now consider invasive species to be one of the top two threats to this planet's native plants and animals (the other is habitat loss). Invasive species cause major environmental damage amounting to almost $120 billion a year. Yet invasive plants are still commercially available, and a few of them remain wildly popular. Japanese barberry, for example, is one of the hottest-selling plants in the nursery trade, and Norway maple is one of the most widely planted trees in the country.

Thank you sir, may I have another?

It has happened yet again - *sigh*. Wild potato vine (Ipomoea pandurata) has once again been cut to the ground.

Here's the problem, this plant, an herbaceous vine, (related to that chartreuse green windowbox favorite) existed in an area that was made into a recreational park. Despite all thoughts to the contrary, the plant came back a few years after it had been hacked to the ground to create said park. However, the plant doesn't know that things have changed. This (unnamed) park is now manicured and all things not trees get weed whacked. (This seems to be true of all NYC Parks - unskilled labor + pruning equipment = death to all plants not 50 ft tall. I'm not exaggerating). Imagine, a vine growing up a fence in a highly managed park. How unseemly! thwack

Why care? Well, wild potato vine is a New York State rare plant. And this site is its only occurrence in New York City. I am meeting with the park manager next week to discuss long term solutions to protect this plant. Which I've done every year around this time. My suggestion for 2007 is going to be a security guard.

The rarest in the land

Poor Torrey's mountainmint (Pycnanthemum torrei). There has been so much hooey over this population (then scroll 4/5 down) of the globally rare plant. It used to be part of the gorgeous! pristine (in some sections)! rare plant inhabited! 130 acres Kreischer Hill parcel, which was owned by the NYC EDC.

But conservation was not to be. Instead of thousands of years old glacial till sandy soils with their concomitant NYS rare communities and species, we have - what we've always needed! - Target, Home Depot, Bed/Bath/Beyond and a Christmas tree store. Hooray! That was certainly worth destroying the uncommonly occuring, sexually reproducing population of American chestnut. But that's just imho.

*Sigh*

Presently we are trying to conserve the population in situ (stop snickering!). This summer, we did a census of the mountainmint population. A transect was set up parallel to Veterans’ Road West. Every meter was marked off. Perpendicular to transect, 1m squared plots were set up. Within each plot the following data was collected – number of plants, number of individual stems, number of shoots, length of all stems, and the presence and number of flower heads. Casual observation suggests that the plants are grouped in clusters along this transect. This data will confirm whether or not this is the case. If so, further environmental factors will be examined to determine causal factors.

Orchids Found in SI

Today I went out with my pal Ray to root around along Staten Island's south shore...won't say exactly where...and we found two orchid species new to City records – large coralroot (Corallorhiza maculata) and bog twayblade (Liparis loeselii). Large coralroot lacks greenery - it has tawny brown stems and no leaves. This is because it does not photosynthesize. It is saprophytic, meaning it feeds off organic matter, like fungi. It is added in its nutrient intake by a short, stubby, branched root that resembles coral. Small white, purple spotted flowers appear in late summer.

As the name suggests, bog twayblade is found in wetland, open habitats. It has unremarkable yellowish-green flowers that are only 1/4” long that bloom in late summer.

Rare Plant Hunting

Today I romped around Pelham Bay Park in the Bronx. I located NYS-listed rare plants Eastern gama grass (Tripsacum dactyloides) and common persimmon (Diospyros virginiana) on an upland copse in Goose Creek Marsh. I noted something interesting – that the Eastern gama grass only appears ringing the upland perimeter of Phragmites, which is highly invasive. Where Phragmites was not observed, gama grass was also absent. T. dactyloides was noted as bearing seeds, but it was too early for the persimmon’s fruits.

Also found a patch of Canada mayflower (Maianthemum canadense). This patch was very small in both size and number of leaves (ramets). Given the undisturbed nature of the site and the seemingly high habitat quality, one would expect to find the plant extensively clonal here - aka a much larger patch. This population will be incorporated into my study of habitat quality using mayflower as an indicator species for forest quality.

New plant listings found and identified from this trip include: climbing hempweed (Mikania scandens), water plantain (Alisma subcordata), three-nerved joe-pye weed (Eupatorium dubium); these are all NYC rare and new finds for the borough. I also found the NYC willow herb (Epilobium coloratum) and the not rare but still cool tussock sedge (Carex stricta).

Avalon's Dunes

In our second installment of looking at plants in Avalon, NJ, we go from the garden to the dune, much more fun. I didn't walk on the dunes, mind you. Just along the designated pathways.
Dunes! Filled with grasses and forbs.
Maybe the most famous dune occupant, beach grass (Ammophila breviligulata). This is the species that is planted in rows whenever there is an effort made to save the beaches from erosion. Through its extensive root system, beach grass binds the loose sandy soils together. This stability allows other plants to colonize the dunes. Avalon has been preserving it's dunes for over 30 years. (They are allowing new development in the salt marshes, however, but that's for another day).
This is a neat plant, trailing wild bean (Strophostyles helvola). It's uncommon in New York City, but fairly common in NJ - because it loves these outer coastal plains. It's a ground-trailing vine in the pea family. This plant is very similar to pink wild bean (S. umbellata), which is rare in NY State.


Note the fruits are encased in bean-like pods.

Avalon's Gardens

I'm lucky enough to be able to spend Labor Day weekends down the shore in Avalon, NJ. (And, it is "down the shore", not "at the beach"). Between lying on the beach, under an umbrella and jaunts in the ocean, I, of course, walk the neighborhood and scout out plants. Here, I present "Avalon's Gardens: Dos & Don'ts".

A definite do! Switchgrass (Panicum virgatum) is a great choice for the full sun and well-drained soils that dominate the yards in Avalon. This is a grass that you'd find occurring on its own in such a site. (Ignore the exotic boxwood and juniper flanking it).
A definite don't! Japanese barberry (Berberis thunbergii) and purple loosestrife (Lythrum salicaria) are highly invasive! And, what's with the cedar chip fetish?
Yam-leaved clematis (Clematis terniflora). Looks great, smells nice, invasive. A don't. This photograph was taken in someone's front yard. You know where else I saw this plant? Along the trees of the Garden State Parkway, for miles and miles.
Ah no! Chinese silver grass (Miscanthus sinensis) - invasive! (And obnoxiously huge, no?)

To end on a positive note - a joe-pye weed(Eupatorium sp.). A definite do, and quite the looker. Its a great nectar plant for butterflies, and has interesting seedheads in winter.

Happy Halloween!

Doll's eyes (Actaea pachypoda {syn. A. alba}) MMMWAH!

Creepy, isn't it? The infructescence of doll's eyes makes an impression on you - wandering in a dark wood in fall, suddenly, it feels as though there are eyes on you. You look down, and it's true!

In late spring, when this member of the buttercup family (Ranunculaceae) is in flower, it would be easy to overlook, with it's small, white, star-like blooms held aloft sharply toothed, compound leaves. At this stage, it closely resembles its congener, red baneberry (Actaea rubra). But the real fun comes later in the season, when stark white berries with dark "eye" spots appear in early fall. (This spot is a persistent stigma from the flower). These berries are collected on a grape-colored stem, which makes quite a striking contrast that lasts over a month. And as tempting as it may be, don't eat them - they are poisonous.

In New York State, doll's eyes is considered "exploitably vulnerable", which means people poach it in the wild. If you come across it, for goodness sakes, don't pick it!

However, it would be easy to enjoy this plant at home - it makes an excellent addition to any garden in partial shade. Growing to 2.5 ft tall, both baneberries are long-lived and willingly germinate from seed.

Invasive willow threatens wetlands, rare plants in East

Egads - another one.

From The Boston Globe

A European invader has been sneaking onto the New England coast, infiltrating and undermining the natives.

The large gray willow, a shrub or small tree that spreads rapidly and closely resembles our native pussy willow, has been flying under the radar for years, colonizing the edges of ponds and crowding out rare plants and animals throughout the eastern United States. It was just identified this spring.

Other countries that have been invaded by the species, Salix cinerea, also called the European gray willow, paint a grim picture. New Zealand considers it a major "pest plant". Australia calls it the worst of the invasive willows and warns it can cross-pollinate with other willows.

There is concern about the threat to coastal plain ponds that are host to a whole complex of rare insects, animals and plants, including the Plymouth gentian, rose coreopsis, hyssop hedge-nettle and slender marsh pink, as well as rare dragonflies and damselflies.

The European willow's presence is confirmed for Cape Cod and Rhode Island. It is expected to show up in coastal areas stretching from Maine to Long Island. The Harvard Herbaria in Cambridge, Mass., has a specimen collected in Old Orchard Beach, Maine, in 1967, so the willow has a lengthy head start on efforts to control it. (Yet ANOTHER reason why herbaria are so important!!)

The full article from The Boston Globe

More on Salix cinerea

Good Gardening: Medley

Solomon's seal (Polygonatum biflorum)

Solomon's seal, with it's tall, arching stems and showy foliage, is a statuesque addition to any shade garden. Once in the ground, they require very little attention.

Flowering dogwood (Cornus florida)

This is another example of why everyone should have a flowering dogwood...the rich fall foliage.

Evergreen woodfern (Dryopteris intermedia) and Sensitive fern (Onoclea sensibilis)

These ferns are attractive as border plantings in moist locations.

Mist flower (Eupatorium coelestinum)

Beloved by gardeners & butterflies alike, this easy-to-please member of the aster family (Asteraceae) is a rampant spreader, so give it lots of room.

Stalking the Wild Orchid

Sadly, wild plant pilfering happens all the time. People can be stupifingly self-centered & just plain evil when it comes to rare vegetation - as chronicled famously in The Orchid Thief. But maybe too I am a little more trusting, I didn't ask the NY Times reporter to don a blindfold.

Here, garden writer Ken Druse takes a walk with the Nature Conservancy in the Pine Barrens of New Jersey...and I am jealous.Read more

Guess what I found!

Somewhere in Van Cortlandt Park in the Bronx...

Schreber's aster (Eurybia schreberi {formerly Aster s.})

This native species has adapted to life on forest floors by being colonial. That is, it reproduces vegetatively, producing a leafy carpet. When it's happy, it will put up flowers, which are white. Easily confused with large-leaved aster (E. macrophylla), which has light blue blooms. But let's say you missed the boat on the flowers, as I did...what to do? Examine the basal leaves closely. Both species have heart-shaped bases. However, in E. schreberi, if you spread the bases, there is a rectangular shape between the lobes. Large-leaved is simply heart shaped. Obscure? You bet. That's why we botanists make the big bucks. It's important to differentiate between the two, since Schreber's aster is rare in New York State. Both species are uncommon in NYC.

Rough-leaved goldenrod (Solidago patula)

But that was just a teaser. I knew that plant was there. The "guess what I found" is this goldenrod. "They are a dime a dozen," you are thinking. Friend, you would be wrong.

Sure, Canada, early, gray, and rough-stemmed are common along roadsides and in old fields. Even seaside goldenrod isn't limited to its namesake habitat. But S. patula is one of the fabled "wetland goldenrods", which makes it unusual & rare in NYC. I had never seen it.

I found it quite by accident, as is the case with the best botanical finds. I knew it was a special goldenrod, and so marked the spot to return the next day. I came back armed with my Gleason & Cronquist and Britton & Brown. When it keyed out to S. patula, it felt as though I had just won a prize - a new find for the city!

HGG: Canada St. Johnswort

In today's installment of "Home Grown Greenery" we take a closer look at Hypericum canadense (Canada St. Johnswort). This native species is a member of the Clusiaceae or Mangosteen family. As you may have guessed, this family has its center of diversity in the tropics, with a few genera found in the more temperate climes. In fact, trees & shrubs are the more common plants found in this family, which makes the herbaceous H. canadense all the more intriguing.

Canada St. Johnswort may be an annual or perennial, but is always diminuitive, growing only to 20 inches tall. As with other Hypericum species, its leaves are opposite from each other, & alternate at 12/6 o'clock & 3/9 o'clock. Thus as one looks down the stem from above, they notice a cross pattern. This is the derivation of "St. John" (wort is the Old English word for plant).

From July through September, tiny, 5-petaled, yellow flowers appear on the tips of every stem. If pollinated, fruits develop - dark red conical capsules containing many small seeds.

The best place to find Canada St. Johnswort is in open, sunny, poorly drained areas such as marshes. This particular plant was found in southern Staten Island in an area of sandy glacial outwash with ribbons of clay soils. This plant is rare in NYC, as are its brethren - there are 5 other Hypericum species in the five boroughs, four are native, all are uncommon. One of the biggest threats to its future is the encroachment of trees & shrubs - shaded out by woody species as a result of succession. This is, of course, with the understanding that the biggest threats to our flora are always lack of conservation leadership. NYC natural areas have been destroyed through development & degraded by exotic invasives.