It has been a curious pleasure to watch the explosion of mushrooms over the last couple of weeks. Seems that one day the gravel drive is smooth and undisturbed, and the next, a rising bubble of white fungal flesh is cracking open the hard-packed surface. 

Two days ago I took a few photos to document some of the variety I am observing.  Note how the colorful, bracket-style fungus below (2nd photo) is pierced by blades of grass!  And that triple-decker beauty is something I’ve never seen before (it’s actually 3 mushrooms emerging at once, one nearly on top of the other).

Late August and September (even October) is typically a good time to see mushrooms in the NC Piedmont, presumably because we tend to get a little more rain then.  Indeed, the last few weeks have brought a lot of rain here, though not to other parts of the United States. (On August 7, the US Drought Monitor   reported that more than 62% of the contiguous United States was under moderate or worse drought conditions.  Add in those regions with “abnormally dry” conditions and the number goes up above 78%.)

Keep in mind that the mushroom you see sprouting along the trail is one small part—the spore-producing part—of a massive network of fungal threads beneath the soil surface: the mycelium. Fungal mycelium is “a complex fabric of cells permeating virtually all land masses of Earth, from the tundra to the tropical rainforests” (to quote Paul Stamets, author of Mycelium Running).  Only a portion of the fungal species actually produce the mushrooms that we see; many others have microscopic or sub-microscopic fruiting structures.  And what do we know about the diversity of the mycological kingdom?  One expert has estimated that only 5% of fungal species on Earth have been described!

The North Carolina Botanical Garden is involved in the effort to learn more about the diversity of fungi, through the specimen collections of the UNC Herbarium.  It turns out that our Herbarium holds more than 25,000 fungal specimens.  This mycological collection was started early in the twentieth century by Dr. William Chambers Coker, botany professor and founder of the Coker Arboretum, and was added to significantly by Dr. John Couch and Ms. Alma Holland Beers, later botanists at the University of North Carolina.  The fungal  collection is getting an overhaul and reorganization this summer by intern Daniel Adams, who will also begin the process of digitization to make this resource available to scientists everywhere.  This work is part of a very large, National Science Foundation–funded project called The Macrofungi Collection Consortium: Unlocking a Biodiversity Resource for Understanding Biotic Interactions, Nutrient Cycling and Human Affairs.  The UNC Herbarium (and, by extension, the NC Botanical Garden) is one of more than 30 institutions cooperating to make the information on fungal specimen labels available online. Read more about our Charles T. Mohr Herbarium Intern and his work with the fungal collection, here:  http://herbarium.unc.edu/2012internMohr_Adams.htm

You might ask, “Why?”  From the Macrofungi Collection Consortium  description:

From wood-rotting fungi that clear the forest floor of dead wood to the chanterelles and truffles in our food, mushrooms and other large showy fungi (macrofungi) play a critical role in the lives of plants and animals, including the health and welfare of humans. Yet the numbers of different species of these fungi are largely unknown.

Understanding the biodiversity of fungi will be critical in analyzing the effects of habitat change, nutrient cycling in ecosystems, and distributions and diversity of host organisms.

Scientists in the United States have been studying and collecting macrofungi for the past 150 years, which has produced a legacy of some 1.4 million dried scientific specimens, in 35 institutions in 24 states.

These institutions joined forces in an effort to digitize and share online data associated with these specimens. The resulting resource will enable a national census of macrofungi, and will allow researchers to better understand the diversity of these organisms and the relationships between macrofungi and the other species, such as lichens, in which fungi and algae form a wide variety of biotic partnerships.

One of the uses of mushrooms/fungi that I find most interesting, and that isn’t specifically mentioned in the above “justification” for the Macrofungi project, is bioremediation.  Because of their ability to break down the molecular structure of some difficult to destroy toxic substances, fungi seem to have great potential for helping to clean up toxic spills (including petroleum) and polluted water supplies.  See for example: http://www.fungi.com/blog/items/mycofiltration-for-urban-storm-water-treatment-receives-epa-research-and-development-funding.html

Meditate a while on that, if you will. It’s a good time of year to do so.

—Laura Cotterman

In the spirit of the name of this blog, I’m going to share with you a bit of what is going on “around the garden” these days.  It has been a very hot summer in this part of the country—many days with temperatures well above 90 degrees F. So, there is watering to do, and the job of keeping up with the growth of wanted, as well as unwanted, plants, even though we are short-handed.

This week, some of our Horticulture and Conservation staff are at the Cullowhee Native Plant Conference in western North Carolina, learning and networking with other folks who are devoted to propagating and preserving native plants. Thanks to the conference organizers, some of our student interns could attend as well, on scholarship. If you don’t know about this annual event, you should!

There are lots of these beauties, above, blooming here at the Garden: Crimson-eyed Rose-mallow (Hibiscus moscheutos) is in our Coastal Plain Habitat garden and other beds and ditches about the landscape. Interesting how nice the spent flower appears after it twirls itself shut and falls onto the worn boardwalk:

And have a look at this pink-flowered variety, which is planted right in front of the Education Center:

For weeks now, I’ve admired the quantity of pollinators visiting the many different species planted in the new Piedmont Habitat Garden. Here are some wasps (sorry, I haven’t ID’d these yet) on Northern Rattlesnake-master (Eryngium yuccifolium):

Here is a tall and stately grass that I am partial to: Gamma Grass (Tripsacum dactyloides). It is a relative of corn, and apparently deer love to eat it. I took this photo a couple of weeks ago of a plant outside our deer fence—need to go back and see if it has been munched.  The male flowers, with dangling anthers, are toward the apex of the inflorescence, whereas the female flowers, which will become the tasty kernels, are toward the base—you can recognize them by the forked/branched two-part stigma.

Returning to the fruiting theme of last month’s post, here are two fruits on their way to ripening, but not quite yet: Northern Spicebush (Lindera benzoin)—the drupes will turn bright red by fall:

and, our old “weedy” friend, Pokeweed (Phytolacca americana):

Isn’t it great that you can find purple berries, green ones, and even a few last white flowers, on the same plant?

Finally, the North Carolina Botanical Garden has been doing its part to encourage youngsters to connect with nature this summer.  Last week’s session of Nature Explorers camp, “Junior Naturalists” (for 8- to 10-year-olds), included some memorable moments with birds and insects at Mason Farm:

as well as fun in the classroom, where campers turned one of their counselors into a “tree”:

We feel pretty fortunate to be in the thick of all this natural and human activity.

—Laura Cotterman

Recently, while immersing my senses in a bowl of peaches and blueberries, I thought about the marvelous presence of fruit in our world.  Here I sat, eating some of the sweetest products of nature, oblivious to the fact that my behavior has been carefully tuned by the plant world.

I am referring to the fact that fruits essentially exist so that animals like me will eat them and move the seed/s buried inside to a new location—where at least some of the seeds will stand a good chance of sprouting and making new plants.  Never mind the fact that in our current situation, we usually flush our “waste”—containing those blueberry seeds—away!  Peach pits do land in my compost pile and occasionally sprout, but they don’t usually make it to tree stage, sadly.

This year the fruiting season seems to have come early: not really a surprise, as we observed many plants flowering early.  Have you every stopped to notice the many, many kinds of fruits out there in our woods, fields, roadsides?  Now please note that I am using the term fruit in the most generic of senses, as you can see by the photos below:

This Thimbleweed (Anemone virginiana) makes a thimble-shaped head of achenes—which are rather dry, hard, thinly covered (no “flesh” to speak of) seeds. You can see that “thimble” forming when the plant is in flower.  Maybe the achenes are not eaten, for come winter, the heads explode with fluff, which makes me guess that they float away on winter winds.

This Baptisia makes pods that contain several “beans.”  I wonder who eats these legumes?

Wish I’d gotten a better photo of the fruits of New Jersey Tea (Ceanothus americanus): the 3-lobed (3-seeded) “drupes” are so compactly triangular, and they are blushing red right now.

It may be hard to think of a Hemlock cone as a fruit—and really it is not. But the winged seeds (“samara”) developing in there will provide a dense form of protein for many birds and mammals.

I was surprised to see, already, the ripening clusters of drupes on our potted Smooth Sumac (Rhus glabra) plants last week.  What a plant for color!  Fuzzy, red clusters of fruit amid those luxuriant leaves on pinkish stems.  When the leaves turn red in late summer/fall, it is spectacular.  By the way, some of the fruits we eat are defined as drupes—peaches and cherries for instance, as they contain a single stoney seed with a fleshy outer layer.

The berries of Solomon’s Plume (Maianthemum racemosum) are green now, but pretty soon they’ll ripen up with fine red spots all over, giving them a ruby red look. The way this plant leans over, I am guessing that some fairly small, low to the ground animal eats those berries—though I did read in one source that birds consume them.

I hope you will take notice of the abundant and diverse fruits that our native plants provide.  Many of these will be ripe and ready food for wildlife in the cooler, darker seasons when insects are less available.

—Laura Cotterman

The new Piedmont Habitat display garden at the North Carolina Botanical Garden has given us the opportunity to try out some new plants. The fact that this particular garden is occupying a former (paved) road corridor meant we could grow plants that need a lot of light (see previous blog post dated December 21, 2011).

One section or “bed” of this garden displays plants found growing on the mineral diabase in plant communities referred to as glades or barrens.  These plant communities are dependent on natural disturbances (e.g., fire or herbivores) that minimize competition in the understory and create situations with ample light levels.

You may remember that a few years ago (2009, to be exact) the NC Wildflower of the Year was Piedmont Barbara’s-buttons (Marshallia obovata).  With buttonlike clusters of white flowers topping slender stalks, that Marshallia was described, in our own words, as “simultaneously sturdy and delicate, cheerful and elegant, petite and eye catching.” Its natural habitat is dry open woodlands and sunny edges, and we do display it in the Piedmont Habitat Garden.  In fact, it has just about finished up blooming.

But take a look at this other, gorgeously tall, purple-tinged Barbara’s-buttons that began blooming last week in the diabase glade section of the Piedmont Habitat. (Note that large leaves with serrated edges in the background are from a Parthenium plant—not the Marshallia.)

Our staff collected seeds for this beauty—“Oak-Barrens Barbara’s-buttons”—at a protected diabase glade site where powerline right-of-way maintenance and prescribed burning have enabled remnant populations of shade-intolerant plants to survive.  The nomenclature of this Marshallia species is currently being worked out by Dr. Alan Weakley, curator of the UNC Herbarium .

This photo shows how Marshallia sp. 1 looks as it is just starting to bloom.

Don’t expect to see this plant offered in our Daily Plant Sale.  It is very rare, “known from three extant populations and one extirpated population, in Granville County, NC, and Halifax Co., VA, where [it is] associated with numerous rare and disjunct taxa of prairie or barren affinities” (from Weakley, Flora of the Southern & Mid-Atlantic States, May 2011 draft). The Garden’s policy is not to offer for sale plants known to be exceedingly rare or threatened, with few exceptions: 

 “The overriding policy of the North Carolina Botanical Garden is that its activities will support the conservation of the plants and natural areas in North Carolina and the Southeast. Our sale and promotion of [the] horticultural use of rare plants shall be accepted when these activities benefit conservation goals [my emphasis] and will be rejected when these activities compromise conservation goals.” 

Read the full text of our Policy on the Sale of Rare Plant Species here and come by to see this intriguingly rare Marshallia soon!

 —Laura Cotterman

Weeds are big attention-grabbers at this time of year.  Last weekend, as I weeded a particularly wild and unmanaged wildflower plot at my home, I thought about my attitude toward weeds.  The modest 4-by-4-foot bed I was working in is where I have randomly, with no attention to design, planted perennials brought home from the North Carolina Botanical Garden.  The verb “planted” suggests more intention than I can claim:  it’s more like I hastily stick them in the ground, water once, and nearly forget about them.  Furthermore, over the years, some non-native, albeit pretty, plants—for instance blackberry lily—have found their way into this square of ground. I can’t seem to refuse a pail-full of plants passed along by a friend. Fortunately, these nonnative delights have remained understated (i.e., under control). But not so the “weeds.”

On this spring Saturday I was yanking the usual—yellow clovers, sorrels, Bermuda grass—from this unruly bed.  After a few minutes, one aggressive interloper started raising a sense of alarm in me. A delicate, clambering, white-flowered vetch, this annual, it turns out, is not native; I did NOT put it there!

Vicia hirsuta, tiny vetch, comes from Europe and Asia, though by now it is found throughout eastern, southern, and western North America; only the mid-sections of Canada and the U.S. are unaffected.  Searching some sources on the Web, I found that V. hirsuta is viewed as a weed of agricultural crops in a lot of places, including Eastern Europe and Russia.  With its hair-thin but tough tendrils it will hang on stubbornly to other plants, it continues growing after you pull it, unless you grasp it at the very bottom and extract the roots (and believe me, it is hard to find the “bottom” of this viney-thing).  The many short, two-seeded pods are quick to ripen in the spring, too.  It wouldn’t surprise me to learn that the seeds persist in soil for many years.

(photo by Jean Pawek)

What is “a weed”? A plant we don’t want that more or less aggressively invades a space where we’d like to be growing something else?  Well, yes!  Often it is not native to our  geographic region—though this is not always true (think poison ivy). It seems that we never would have come up with the concept if we hadn’t developed the impulse to cultivate the earth with plants that WE wanted.  Couple that with the fact that we move plants, soil, and our bodies, to which seeds attach themselves, around the globe—it’s no wonder there are a lot of “weeds.”

Yesterday I looked through a shelf of books on weeds in our library at the Botanical Garden (did you know that we have an excellent library, and anyone is welcome to come by to use this treasure trove of references? note: books must remain on the premises). Take a look at these marvelous titles I found: 

• A Manual of Weeds with Descriptions of All of the Most Pernicious and Troublesome Plants in the United States and Canada (by Ada E. Georgia, 1927)
• Wildly Successful Plants—A Handbook of North American Weeds (by Lawrence J. Crockett, 1977).  

“Pernicious” and “Troublesome” are terms freighted with bias—understandably so, I might add. But the second title captures the essence of “weeds” for me.  Weeds are plants that have been wildly successful in occupying multiple geographies and reproducing themselves there.  There are many, many strategies for accomplishing this, including tendrils and a vining habit that make the plant hard to remove, seeds that can germinate for several to many years after dropping to the ground, rhizomes that break off in the soil and re-sprout after the plant has been pulled up (a good example in my garden is sheep-sorrel, Rumex acetosella), and one of the most clever of all—getting an animal (like us) to carry you to a new place where there are no predators (herbivorous grazers and insects) that like to eat you or diseases that will kill you.  For this last, think of Japanese stiltgrass, Microstegium vimineum; even goats won’t eat it!

I am not a very diligent gardener.  The long hot summers here leave me defeated by July, so I often don’t attack my garden weeds as heroically as I might. I give up and by September, they’ve dropped a million and one seeds—a situation that, I am all too aware, makes the next year even more challenging.

The tiny vetch in my garden caught my eye last year and I did pull at a few tangled strands.  It gets going fairly early in the spring and displays miniscule white flowers soon after.  But the thin stems and slender pinnate leaves were sort of appealing, in small numbers, so I didn’t take it seriously.  What a mistake!  Short, fuzzy seed pods appeared very quickly, and before I knew it, pulling was pointless because each yank released a crop of seeds from the now brown pods.

I try not to judge any plant too harshly, calling it names and cursing its very existence.  After all, it is only doing what comes naturally!  Nevertheless, weeds do need to be dealt with in a timely manner if we are going to be gardeners.  I’m in favor of the slow and steady method of “editing” out (a term used by “queen weeder” at NCBG, Sally Heiney) the plants we simply don’t want taking up valuable space in our cultivated ground and who generally won’t serve as food and shelter for our native species of insects—who, in turn, serve as food for the native birds we take pleasure in seeing and hearing when we sit down on the porch to rest and drink a glass of cool water after a morning of weeding.

—Laura Cotterman