Where Trees and Summer Wildflowers Cohabit

Since I gave such short notice about the canal walk tomorrow, I'll offer this virtual tour. Along the DR Canal towpath, just west of Harrison Street in Princeton, there's a nature trail loop. Most people head to the canal with a bike or running shoes to clock some miles, but for those who want to take in their surroundings, the winding, mowed trail offers a lot of wildflower interest this time of year.

While most habitats hereabouts are either dense forest or open field, the trail loop is more of a glade or savanna, with scattered trees offering many gradations of shade and sun to please the eye and meet the varied needs of diverse wildflowers.

Most of the trees along the winding trail are oaks--some planted long ago by the university when this strip of land was tended as an attractive entryway into campus. Oaks tend to have thick, fire resistant bark that can survive the sorts of periodic fires that once would have sustained open woodlands such as this. One of the oaks is a bur oak, uncommon in NJ but famed in the midwest for the bur oak savannas it lords over with its dark spreading limbs contrasting with the deep green obovate leaves that remind me of bison. Many of these savannas have been restored using prescribed burns.

Here's the wildflower that led to the creation of this mini-preserve and nature trail. The cutleaf coneflower has a rosette of leaves at its base. At some point around 2006 I was walking along the towpath and noticed these basal rosettes, which were surviving what were almost weekly mowings at the time. There were many of these clumps scattered throughout the broad area between Carnegie Lake and the towpath, all of which were getting mowed down before they could bloom. It seemed a waste of natural "talent", so I contacted the DR Canal State Park staff, and they agreed to reduce mowing to once a year in that area. There was a bit of a complication because the land is owned by the university, but they were amenable as well. The show of cutleaf coneflower that first year was spectacular.

Seeing the attractive result, the park staff later added a trail and a sign. My role is to send a reminder in late winter to make sure they mow before spring growth begins. Less mowing, more wildflowers--all in a day's rest.

To the right of the sign is a patch of native switchgrass--a tallgrass prairie species that propers in the east as well and is sometimes planted for ornamental purposes.

There's also a patch of knapweed, a nonnative which appears to be Tyrol's rather than the highly invasive spotted knapweed that's moving east from the midwest.

There's a plausible cause and effect here, given that the larvae of ladybugs are voracious consumers of aphids, numerous on the underside of this common milkweed leaf.

Deertongue grass, another native grass that is sometimes used as an ornamental, for instance in the raingarden in front of the Whole Earth Center, prospers along the trail.

The various species of goldenrods are just coming on. Goldenrods get wrongly blamed for being allergenic, because they bloom at the same time as the inconspicuous ragweed.

Some benches were donated to provide restful views of the rowers laboring away on Carnegie Lake.

If you take a closer look at the shore, you'll see yellow pond lilies, lizard's tail and rose mallow hibiscus.

It's really gratifying to see that wildflowers are growing more numerous under the state park's annual mowing regime, with lots of ironweed elevating above the other vegetation,

and expanding patches of Joe-Pye-Weed. This species has hollow stems that provide homes for the local insects.

At one point on a bright morning walk last weekend, I had to stop for a moment, take in the majestic oaks, the bountiful wildflowers extending down the long corridor of the winding trail, a downy woodpecker busy on a limb overhead, insects feasting on the nectar--and realize that we actually did accomplish something here that is lasting, and without spending a nickel. A change in management released the native growth force that had been there all along. Managing with nature rather than against it brought better results with less work.

One fun aspect noticed this year is that the mowing crews appear to be getting creative with the trail mowing, adding attractive lookouts,

and a new circular clearing. Not sure what the purpose of this one is, but it could well serve as habitat for low-growing species that can't compete where there's only one mowing per year.

A favorite sedge, fringed sedge, grows along the trail edge here and there.

Another favorite: wild senna, which in this photo looks a bit like a beehive hairdoo wig that's been in the attic too long. The seedpods are forming below the last few blooms at the top.

Showy tick trefoil is another legume that forms pods quickly beneath blooms higher up. Anyone heading off trail may find these on pantlegs after the walk.

Sticking with the theme, pokeweed berries form lower on the stalk, with flowers higher up.

Pokeweed is usually considered too rambunctious for a garden, but is very attractive and at home in this floodplain.

The long pods of Indian hemp, which is related to milkweed, not that miracle plant hemp, which still remains tragically illegal to grow in the U.S.

This native Clematis virginiana has toothed leaves, while the non-native Clematis autumnalis sometimes found in gardens has smooth-edged leaves. Both can be highly invasive in a garden, popping up in new, undesired spots in the yard.

A really bad actor is this non-native porcelainberry, with leaves and viney growth habit reminiscent of wild grape. Its berries turn white, blue or pink--very attractive but avoid the temptation of picking them and transporting them elsewhere. You can see this kudzu wannabe's over-the-top aggressive growth behind the Clark House at the Princeton Battlefield, and it's been colonizing new areas of Princeton. In past years, it looked like it was going to overwhelm all the wildflowers along this trail, but this year the balance is better for some reason.

The elderberry bushes were getting mowed down each year, which kept them from blooming and making berries, so I've started tagging them to alert the mowing crew in late winter to mow around them. Little interventions like that can make a big difference, simply by making it a little easier for the native growth force to do its thing.

The trail got windier, and actually more interesting, after the stiff winds of Hurricane Sandy, when many trees fell and the trail was mowed to circumvent them.  

Jewelweed is a common annual whose tubular flowers attract hummingbirds. Try touching the swollen seedpods to see what happens.

The trail loops back to the towpath. Walking back towards Harrison Street, you'll see the elephant-ear sized leaves of a Princess tree (Paulownia) that gets cut down each year or two by a different crew that's responsible for keeping vegetation controlled along the canal itself.

Climbing hempweed--that's not related to hemp either--is a native vine common along the edge of the canal.

Sometimes it has parasitic dodder mixed in.

That's the hike. Oh, I forgot the figwort--a tall wildflower that only a botanist could love. It's not blooming in the photo, but the flowers are so small that you're not missing anything. I've only seen maybe five plants of this species in all of Princeton, so it's special to see it has survived another year on this island where land and lake, tree and wildflower, native growth force and human tending, all cohabit so pleasingly.

Canal Wildflower Walk This Saturday

I'll be leading a walk along the canal this Saturday, August 22, starting at 8:30am. Morning light adds to the freshness of this landscape. We'll meet along the towpath just west of Harrison Street, where there's a nature trail sign. All are welcome.

Wildflowers have been at their peak this past week--a perk for all of us who haven't fled Princeton in August--and there should still be a good show this weekend. We'll focus on the nature trail loop that I "catalyzed" back in 2006, when I alerted DR Canal State Park staff that there were some wonderful native wildflowers that were getting mowed down between the towpath and Carnegie Lake. The park staff reduced mowing to once a year (less work!), added a broad, well-mowed trail that connects in multiple places to the towpath, and the native flora has responded by growing in greater abundance each year.

The nature trail threads through Princeton's closest approximation of an oak savanna, where there are enough openings between trees to allow summer wildflowers to prosper underneath. All of these Hollow-stemmed Joe-Pye-Weeds are facing north, towards a gap in the tree canopy.

We'll see how natural and cultural influences--from canal building to hurricanes--have combined to shape this diverse, dynamic floodplain habitat.

Parking: There are two small parking lots at either end of the Harrison Street bridge. More distant parking is in the Lake Lane area, just off Harrison St. north of the lake, and at a lot on Washington Road just south of the towpath. If you get there late, it should be easy to find us along the trail loop. This link should take you to a map.

High Season for Floodplain Wildflowers

This is high season for floodplain wildflowers in Princeton, the sorts of native plants that also thrive in raingardens. The first rose mallow Hibiscus (H. moscheutos) appeared one morning about three weeks ago like a big eye looking out from the backyard garden. They're still going strong, and must be impressive along the banks of the Millstone River, easily accessible by boat, upstream of Carnegie Lake.

I planted one in a client's backyard swale, and it delighted them with its first bloom a few days ago, only to be later bombed by a branch from an ash tree towering overhead. The large branch, which landed squarely on the newly planted garden, appeared to be perfectly healthy, and there was no recent weather to point to as cause. It was a freak event, the garden rebounded, but still there was something uncanny about the timing.

Other floodplain wildflowers in bloom are wild senna (pictured), Joe Pye Weed, cutleaf coneflower, and cardinal flower. Boneset, whose bloom marks the climax of pollinator activity, is just opening up.

A couple other native species that haven't been seen growing wild in Princeton but add to the blooming power of our backyard is Culver's Root (past bloom by now) and cup-plant--a robust plant in the Silphium genus that towers over all others, except of course, the trees.

Roosters in Princeton

To all the voices that hold forth in Princeton, add some cockadoodledoos. I had heard that there were some roosters among us--a painter who grew up in South Africa told me a few years ago the sound made him feel at home--but had not heard any until this past month. One was east of Harrison Street a few blocks, which I took the liberty of photgraphing. The other is within crowing distance of town hall.

The legality of having poultry in Princeton comes up now and then. There are some ordinances left over from the borough/township days that were contradictory. The straightest answer I got when I looked into it was from the town's former animal control officer, who said they are legal, or at least tolerated, as long as the neighbors are happy. It was my impression that roosters were not permitted, but it may be that the happy neighbor rule determines whether any ordinance, written or improvised, is enforced.

Though a rooster would never tell you this, they aren't needed for egg production. We'd have to ask the owners if they intentionally bought roosters. Chickens are sold when just a couple weeks old, when sex identification can be tricky. Famed Princeton resident Joyce Carol Oats said, in response to a question I asked after she read from her memoir at the Princeton Public Library, that chickens in general and roosters in particular were an important part of her childhood.

We currently have one Pekin duck and four Aracana chickens. The chickens are quiet sorts, but the duck can speak out at various points during the day, calling for more food, or announcing to the world that it is now waddling across the lawn. Neighbors tell me they like the sounds, as a rural salve for the traffic noise on Harrison Street. The droppings disappear into the grass, and any scratching the chickens do leaves our flower gardens undisturbed.

As pets, they are low maintenance. Clean the coop now and then, make sure there's food and water in the backyard, open the coop in the morning, close it at night. We free-range them, meaning they have the run of the fenced-in backyard. We have lost a few to hawks over the years, usually in late fall and winter when wild prey are less available and the birds have less cover. It can be traumatic, but it brings us up against important issues of life and death, pet vs. livestock, quality of life vs. longevity, risks and rewards, and our relationship to the wild animal community that also calls Princeton home. Interestingly, it's the white birds that the hawks have left alone, as if hawks, too, associate whiteness with some otherworldly nature.

The chickens have shown no desire to fly away, and the duck is so heavy that she has even less chance of clearing a fence than the contraption the claymation chickens built in the movie Chicken Run. The chickens lay eggs most days, and the duck produces one egg per day like clockwork. An Italian neighbor, who barely speaks english, knocks on our door periodically, seeking a dozen duck eggs for her Chinese daughter in law. Perhaps the greatest pleasure, in a town where yards go unused and can tend towards sterile display, is seeing how much the birds appreciate and take full advantage of what the yard has to give.

Though a rooster might help protect the hens, our "guard duck" performs a similar role while producing copious amounts of eggs. In addition to her big, boisterous voice during the day, at dusk she assumes her post just inside the coop door, her beak a formidable weapon ready to unleash against any would-be intruders.

A previous post gives more details, and local sources of chicks. Rosedale Mills told me they were selling chickens beyond the optimal April/May season, though it helps if they are fully grown by the time winter comes. 

Trees and Thunderbolts

There's a puzzle in this picture, which shows one tree where two trees once stood. The second tree is evidenced now only by a patch of brown mulch on the left. The story told by Pam Ruch of Morven Museum and Gardens is that a lightning bolt hit the first tree, stripping bark from one side. They thought for sure that the wounded tree would die, but instead, a couple years later, the tree next to it gave up the ghost.

What happened? Apparently, the lightning penetrated into the ground, then traveled over to the root system of the neighboring tree, where the full electrical force was delivered. The effect was a deadly version of an old slapstick routine, in which the target of the punch ducks, causing the punch to land on the next one over. The first tree was conduit, the second tree victim. The first tree bore the visual symptom, the second tree bore the invisible brunt.

There's been a theme of thunderbolts lately. I've been memorizing a monologue of King Lear--part reveling in, part railing against the elements as he stands out in the heath engulfed in a storm, amidst "oak-cleaving thunderbolts" and "all shaking thunder".

And then my friend Perry sent me a photo of what we call the Lone Pine. Its bark, too, has finally been cleaved by a thunderbolt after many years standing alone on high ground at a nature preserve we created about 15 years ago in Durham, NC. There's such a thing as "witness trees", for instance trees at Civil War sites that were alive at the time of the battle. The Lone Pine is a witness tree of sorts, having witnessed the logging of all the trees around it some years before the land was donated to our nonprofit.

The outcome was more sanguine than King Lear's, because these 80 acres had a native seedbank waiting to mend the wound. With trees gone, dormant native forbs sprang to life in the newly abundant sunlight, coating the ground with a tapestry of sedges, grasses and wildflowers. Quail and woodcock flourished in the early successional habitat.

That rich chapter in the preserve's history, dominated by the height-deprived, came to a quick close, with the emphatic rebound of trees. If King Lear had been into land management, he might have railed against the sun-grabbing dominance of trees and the city's rigid ban on prescribed burns, and called on the thunderbolts to start some grass fires to maintain at least a few patches of open habitat, lest he lose the heath from which to call out his bottomless grief to the heavens.

The Lone Pine now has lots of company as young shortleaf and loblolly pines rise thick around it. But something in me misses that younger, more open habitat, when one pine stood lonely and defiant against the sky.

Note: When lightning touches sandy ground, it makes a material akin to glass, which happened some years back along the canal. My theory, untestable but which perhaps would find company in a google search, is that lightning gave early peoples the idea for making glass.

Plant, Run, and Rescue

We did a plant and run at the Princeton High School this past June. The planting was intentional; the running was not. A plant and run is when everyone shows up to plant a garden, but no one comes back to take care of it. I'm the type that's more likely than most to follow through, but the lesson sometimes needs to be relearned.

When my younger daughter expressed interest in doing something along environmental lines at the school, I suggested, not too surprisingly, that she and her friend plant some native wildflowers in one of a number of raised beds that had for some years been growing only weeds. We did, and at least I came away with a high sense of good deedery, owing not only to having involved the next generation in transforming a weed-filled bed into a demo for natives, but also having catalyzed the repair of the gardens' water supply with a well-placed email or two, thereby improving the prospects for all the raised beds going forward.

We had intended to return soon thereafter with mulch, but life intervened, and by the time we remembered, a rainless week later, the plants were looking pretty sad. In the meantime, some students supervised by the school horticulturist had fixed up all the other beds, which is reason to celebrate though suddenly our bed looked neglected by comparison. Still, after a deep watering, careful weeding and a fresh layer of mulch, prospects for recovery were good.

One rainy month later, as if perched on the cog of an internal Mayan calendar, the memory of the garden again surfaced in the mind, leading to our walking the dog over there to see how things were going. Our good deeds had disappeared in a mountain of weeds (there on the right in the photo), while the other beds were growing well-tended swiss chard and beets.

This is where a keen eye comes in handy. There's the cutleaf coneflower in a sea of foxtail grass.

And there's the late-flowering boneset amongst the ragweed.

The thin mulch had done little to discourage the weeds, though it did keep the soil soft enough to allow extraction of a nutsedge with it rhizome system intact--a rare sighting, like seeing baby pigeons.

We carefully liberated the intended plants, which thankfully had hung in there despite the competition.

At some point, the weedy seed bank will exhaust itself, and the native wildflowers will dominate, but after years of growing weeds, this raised bed is a bit like a wild horse that resists taming. It's a good lesson for one generation and a reminder for the other, about the power of weeds and the importance of followup on good intentions.

Let's see, those most recent photos were taken about two weeks ago. Hmmm. I think I know where the evening walk with the dog is headed.

Lose a Tiger(lily), Gain a Paw(paw)

"Come see our tiger lilies!", I was told at a party recently. Naturalists get this sort of invitation now and then. I was a bit skeptical that they were tiger lilies, though, because there was mention of spreading,

and the only tiger lilies I've come across in Princeton are the ones in this photo, behind Conte's. Nevertheless, I took them up on the invitation--my interest piqued by the owner's enthusiasm about these lilies.

Sure enough, they proved to be daylilies, a step above the humble, unimproved orange found in abundance in my yard and many others, but daylilies nonetheless.

Now, I didn't really want to be a bearer of bad news, or even not-so-bad news, since a day lily is still a lily, whose blooming is no less worthy of the owner's enthusiasm for lacking a tiger in the name. People's relationships with plants should not be taken lightly. The plant names that inhabit my brain in abundance tend to take up only the briefest of residencies in the minds of most others, falling away like leaves in a late October breeze.

So when a plant name lodges firmly and resonantly in someone's mind and heart, it's hard to point out that this plant that has come to be known so emphatically as a tiger lily is in fact a daylily. The flower itself is far from plain as day, but "day" can't compete with "tiger" for affection. Which day is the daylily named for? It could be a good day or a bad day, sunny or gloomy, we really don't know. There's no hint of wildness in a day. A day is a mere vessel to be filled with meaning, not a gloriously fearsome beast stalking your yard, fortunately in the benign form of a flower. As I weighed my options, a homeowner's connection to a plant, facilitated by a colorful name, hung in the balance. What to do?

Long a slave to truth, I sought at least to soften the news, by saying that all lilies that grow in Princeton with that classic orange color really should be deserving of the tiger lily name.

After all, with tigers all aprowl on campus, guarding various entryways, the Princeton University Tigers on one side of Nassau Street, Little Tigers on the other, and tiger stripes dominating the color schemes in parades and giftshops, doesn't tigerdom eventually seep into all things and people who reside here long enough? A certain fierceness, perhaps, lurking beneath the civilized demeanor. If nothing else, it manifests in a Princetonian's capacity to leap into the breach and spout copious, tenacious opinions at town hall meetings.

The owners seemed to take the news well enough. If daylilies they are, then daylilies it is, from here on out, though I could tell a bit of magic had fallen away from their front yard. We continued to the backyard, which had that minimally managed grow-what-will look. I was tempted, because of the ground made wet by a very active sump pump--the house having been built on what was likely once a tributary of Harry's Brook--to recommend various of the floodplain flowers that would prosper there, but resisted. There was something soulful and relaxing in this yard that wasn't trying to be anything other than what it is, shaded by Norway Maples and backed by a thick stand of bamboo that obscured the condos just beyond the fence.

I looked around and saw the usual, a pokeweed here, a rose of sharon there, Japanese honeysuckle growing on the fence, and was going to go back to conversation when I happened to look up and saw, what's this? Pawpaws? The northern growing tropical fruit that many of us covet, many have planted, and many must now wait years for any chance of a crop. And here it was, a mature tree loaded with fruit, prospering unbeknownst to anyone in a grow-what-will garden.

I pointed it out, proud of my find, hoping it might make amends for the loss of a tiger lily. Surely, the taste on the tongue of the word "tiger" cannot compare to the lush, yellow, mango-like pulp of a pawpaw. Only later did I realize that I had taken away a tiger, but left them at least with a paw or two. Who knows, maybe it's the distant descendant of the lost pawpaw patch of Harry's Brook, where sabertooth tigers stalked the megafauna of yester ice age.

Addendum: If you dare to walk right up to a tiger lily, you will see the spots on its petals and small black bulblets in the upper axils. The bulblets, if memory serves, can be plucked and planted, to make little tigers. 

Other lilies hereabouts are the towering native Turk's Cap lilies at Morven Gardens, 

with their whorled leaves,

and another, the most truly wild but also the shortest, flying below the deers' radar out at the Mercer Meadows prairie restoration on Cold Soil Road. 

"Reading Getaways" in Local Parks

The Princeton Public Library, ever on the lookout for new programming, will be hosting "reading getaways" at two local parks this summer. Join "friends and neighbors for an hour of silent reading", this Wednesday, July 22nd at 6:30pm at Marquand Park on Lover's Lane, and Sunday, August 16 from 4-5pm at the pond at Pettoranello Gardens. 

The idea comes from the popular "reading invasions" in Buffalo, NY.

Native Trees of Princeton

An attentive reader commented that the page for "Native Trees of Princeton", which I thought I had added along the top of the homepage, does not exist. Funny, I clicked on the "publish" button but the list of trees refused to publish, nor did it magically publish itself during the ensuing weeks when my mind was on other things. Maybe Googles ever more sophisticated software detected that it still needed work, which is to say it was a bit "drafty".

Here it is, nonetheless, published as a post rather than one of those enduring "pages" at the top of the blog. It was created as a step towards fleshing out, or foliating, a rather bare tree list we have on the Princeton Shade Tree Commission website.

My apologies to any native tree species not included here. Please speak up. Catalpas, we'll talk.

ATTRIBUTES OF SOME NATIVE TREES IN PRINCETON 

This is an extensive but informal list of native trees you may encounter in the wild or in your yard, with some description, based on ten years of observation. 

Acer negundo (box elder)--Grows wild. Not commonly planted. It's soft wood can provide good habitat for birds. Considered messy and not very well formed.

Acer rubrum (red maple)--A durable, very commonly planted street tree. Also common in the wild.

Acer saccharinum (silver maple)--Common in yards and in the wild. Not often intentionally planted. Has a reputation for dropping limbs, but performs well in many yards, providing an attractive, open shade.

Acer saccharum (sugar maple)--Less common, but a sturdy, attractive native.

Amelanchier canadensis (shadblow, shadbush, serviceberry, Juneberry)--A very small tree or large bush. White flowers early in spring, supposedly when the shad are surging up the Delaware. Berries edible, but frequently attacked by cedar apple rust, so don't get your hopes up. Even our resident catbirds were disappointed.

Asimina triloba (pawpaw)--Small tree, up to thirty feet. I heard there's a wild stand behind someone's house down across Carnegie Lake, and a substantial patch in a park over in Cranbury. Plant more than one to increase prospects for the often elusive fruit. They clone, so best planted where there's a little room to expand.

Betula lenta (cherry birch)--Grows wild along the Princeton ridge. Not commonly planted in yards.

Betula nigra (river birch)--Beautiful bark and form, frequently sold with three trunks.

Betula (paper and grey birches)--These species are more characteristic further north.

Carpinus caroliniana (blue beech, hornbeam, musclewood)--Common along the Princeton ridge. Not often intentionally planted.

Carya alba (mockernut hickory)

Carya cordiformis (bitternut, swamp hickory)

Carya ovata (shagbark hickory)--Hickories are common in the wild, but not frequently planted.

Castanea dentata (American chestnut)--Devastated by the imported chestnut blight in the early 20th century. Only a few small specimens persist in the wild. The disease does not kill the root, which then resprouts. Backcrossing has developed resistant native varieties with a small percentage of asian genes, e.g. 1/16th Chinese. Some of these 15/16th native trees have been planted in parks and preserves in Princeton in an effort to reestablish the species. A few chestnuts grow along streets in Princeton, but are either Chinese or Japanese. The nut husks are very large and prickly.

Celtis occidentalis (hackberry, sugarberry)--Sturdy native, infrequently seen in the wild, underutilized in planted landscapes. They line Walnut Street across from JW Middleschool.

Chionanthus virginicus (fringe tree)--Very attractive flowers. Small tree/large shrub. Some evidence in Ohio that it can be attacked by emerald ash borer, but more evidence is needed before deciding not to plant.

Cornus florida (flowering dogwood)--Attractive small tree, commonly planted, with berries that provide important nourishment for birds migrating south in the fall. Fairly common in the wild, but an imported fungus has cut back on its numbers. It can be harder to establish that the Korean dogwood, whose fruit are eaten by monkeys in its native Asia.

Crataegus crus-galli (cockspur hawthorn)--Attractive small tree. Rarely found in the wild. Underutilized in planted landscapes, perhaps because of thorns.

Diospyros virginiana (persimmon)--Attractive mid-sized tree. Females bear fruit, which may be appreciated or viewed as messy.

Fagus grandifolia var. caroliniana (beech)

Fagus grandifolia var. grandifolia (beech)--Beech trees are common in the wild along the Princeton ridge, but are seldom if ever planted.

Fraxinus americana (white ash)--Princeton's most common tree, soon to be decimated by the arrival of Emerald ash borer. Though typically encountered in second growth forest, it can grow to a towering height, with a few extraordinary specimens to be found on campus and in older neighborhoods. Planting ash is discouraged, since all ash species will soon be dependent on chemical injections for survival. Anyone owning an ash they wish to keep should get it treated, with emamectin being the most frequently recommended insecticide to inject into the trunk.

Fraxinus pennsylvanica (green ash)--Usually found in wetter conditions, and less attractively shaped, than the white ash. Same susceptibility to emerald ash borer.

Gleditsia triacanthos (honey locust)--The wild variety has thorns and is rarely encountered, perhaps because it was spread by now extinct megafauna. The unripe seed pods have a sweet, edible inner lining. One large specimen can be found near the old gas station at Princeton Shopping Center. Planted varieties, such as those at the new Dinky station and Hinds Plaza, have no thorns, and provide a pleasant, open shade. The tiny leaflets conveniently disappear back into the lawn in the fall.

Gymnocladus dioicus (Kentucky coffee tree)--A remarkable tree, rarely found in the wild, for reasons similar to honey locust. Its very large compound leaves emerge late in spring, and drop early in fall, making the tree ideal for planting on the south side of passive solar houses. They were used in the landscaping for the Dinky parking lot.

Hamamelis virginiana (witch hazel)--Attractive small tree/large shrub. The native species flowers in late autumn, while asian species flower in the spring.

Juglans cinerea (butternut)--Rarely seen. Some are hybrids. The native species has suffered from the introduction of a fungal disease. Efforts are underway to bring back the butternut in Princeton, in parks and nature preserves.

Juglans nigra (black walnut)--Common in some wild areas, and in some backyards. Rarely planted, due to large nuts and the juglone compound emitted by the roots, which can suppress growth of tomatoes and other plants.

Liquidambar styraciflua (sweet gum)--Sturdy, large tree, common in the wild and sometimes planted intentionally. The "gum balls" it drops can be a drawback for some.

Liriodendron tulipifera (tulip tree)--Fast growing, long-lived tree that can reach great size. Flowers tulip-like and attractive, but usually too high up to appreciate. Common in the wild, but not typically planted intentionally.

Magnolia virginiana (sweetbay, swampbay)--Small tree. Can have attractive flowers. Not typically planted along streets.

Morus rubra (red mulberry)--The white mulberry (M. alba, nonnative) is also found in Princeton. A small tree. Bears abundant, edible berries similar in appearance to blackberries. The berries can be messy, and the tree lacks an attractive form. Very tasty berries, though, if you can reach them.

Nyssa sylvatica (black gum, tupelo)--Beautiful fall color. Sporadically encountered in the wild. Long-lived, sturdy. Is becoming more frequently planted along streets.

Ostrya virginiana (ironwood, hophornbeam)--Small tree. Not common in the wild, nor in the landscape trade.

Oxydendrum arboreum (sourwood)--Small tree with bright red fall foliage. Craggy form. Underutilized; may not be well adapted for the nursery trade. More common in the wild further south. Several specimens in Princeton, including one next to the church across from the high school.

Platanus occidentalis (sycamore, plane-tree)--Can be confused with the London planetree, which is a hybrid between two species, one of which is P. occidentalis. Attractive, large tree, with highly ornamental bark. Its more susceptible to anthracnose than the hybrid.

Prunus pensylvanica (fire or pin cherry)

Prunus serotina (black cherry)--The native cherries are attractive mid-sized trees typically found in earlier successional forests. They nearly rival oaks in the diversity of insects they provide food for, and so are very important for food chains.

Quercus alba (white oak)--One of the most majestic trees. The white oak "family" (those with rounded lobes, such as white oak, swamp white oak, and willow oak) are less susceptible to bacterial leaf scorch than the red and pin oaks (pointed lobes).

Quercus bicolor (swamp white oak)--Sometimes planted along streets.

Quercus coccinea (scarlet oak)--Attractive, but less commonly planted.

Quercus palustris (pin oak)--Very common street tree in Princeton. Its lower branches characteristically angle downward and often die back. Many are being lost to bacterial leaf scorch, which causes gradual dieback.

Quercus phellos (willow oak)--More frequently planted than in the past. More common in states further south. Its narrow leaves can form an attractive mulch, somewhat like pine needles.

Quercus rubra (red oak)--Common tree in the wild and along streets. Susceptible to bacterial leaf scorch.

Quercus velutina (black oak)--Encountered in the wild. Less commonly planted than red oak.

Robinia pseudoacacia (black locust)--Native to the Appalachians. Widely planted and naturalized elsewhere. Its wood is resistant to decay, it has attractive flowers, and can achieve a very attractive form with dark, craggy limbs contrasting with the foliage. Can be invasive in some habitats, and can clone, sending up young shoots armed with thorns. But some specimens in Princeton front yards are beautifully formed and well behaved.

Salix nigra (black willow)--Fast growing. Sometimes planted in low areas in the belief that it will dry the soil out.

Sassafras albidum (sassafras)--Attractive tree, common in the wild. Can clone, which may be why it's not commonly planted.

Tilia americana (American linden, basswood)--Attractive. Underutilized. Sporadically encountered in the wild. Linden trees along streets are generally not the native species.

Ulmus americana (American elm)--Though the elm was hit hard across America by Dutch elm disease, Princeton varieties have shown considerable resistance, allowing specimens to perform well and provide shade for many years, even though they may eventually succumb.

Ulmus rubra (red elm, slippery elm)


Native Evergreen Trees:

Ilex opaca (American holly, Christmas holly)--Attractive native, sometimes used in yards. Can grow eventually to 30 feet or so.

Juniperus virginiana (eastern red cedar)--Small tree. Useful in some situations.

Pinus strobus (eastern white pine)--Not encountered in the wild unless in planted stands. Its native range is to the north of Princeton. Can get big, and tends to drop large branches during ice storms.

George Washington Battles the Bindweed

Some may think the battle is long over, carved into stone at Battle Monument, but while George is looking the other way, the bindweed is growing, growing, extending its reach every which way. First it mobs the iris. What could be next?

OMG, it's headed straight towards Monument Hall! Won't someone do something? George, we know you and all those other founding fathers were into plants. You had "a vision for the capital city of the United States that included a botanic garden that would demonstrate and promote the importance of plants to the young nation." It says right there on the website. Congress put the U.S. Botanic Garden a stone's throw away from the capitol building, for heaven's sake. But somehow we all got on a high horse and decided plants didn't matter.

No, that white flower is not bindweed's flag of surrender.

Where George is looking, everything's fine. The left flank is holding. Wild indigo and inkberry continue to grow unmolested.

But wait, what's this? Oriental bittersweet, overwhelming the right flank? What audacity.

Clearly, the wild indigo is calling for reinforcements, albeit very quietly. Don't be so stonefaced, George. Loosen up, take a look around you. Mobilize the troops. That was a great battle you won there, but the battle continues. We need you now more than ever.

Fireworks That Feed the Fauna

Flowers are like slow-motion fireworks, rising up, up, then bursting forth in radiant colors. Hardly noticing the slow build, I was surprised at the sudden unleashing of color soon after the official onset of summer. Behind the purple coneflowers in the photo are the red of beebalm and the white spires of bottlebrush buckeye, whose tubular flowers have been attracting sphinx moths and hummingbirds.

The 4th of July fireworks were impressive, particularly when reflected in Lake Carnegie,

but the slow bloom of a garden has more lasting appeal. It's also more edible, at least for the pollinators. Buttonbush, a favorite of bumblebees, is doing a pretty good imitation of fireworks. Tall meadowrue and Queen-of-the-Prairie (Filipendula rubra) have been adding clouds of white and pink.

Used Pot Thank You

Thanks to all who dropped off plastic plant pots at my house in recent weeks! They're quickly getting put to use for planting up natives, like this soft rush, woodland phlox and rose mallow.

I'm always glad for more, at 139 N. Harrison St. Put them next to the driveway, in from the sidewalk.