Greenhouse Gets a Spring Cleaning

February's native plant workshop, held this past Sunday, was like one of those White Tornado commercials from the 60s, a whirlwind of clean energy zipping through the Mountain Lakes greenhouse, putting everything in order. Pots were stacked, space was cleared for growing the coming season's wildflowers, and Kim led a project to render the unlatchable greenhouse door once again safe and functional.

Prior to the cleanup, we had walked up the long driveway, identifying woody plants as we went. Everyone got up to speed on distinguishing native spicebush from exotic shrub honeysuckle and multiflora rose. And then we started identifying trees by their bark and form. Shagbark hickory lived up to its name, the walnut bark was dark with deep furrows, the red oaks had flat, gray "ski tracks" running down the trunk, and a Kentucky coffee tree had gray "potato chips" flaring out. There were also some very impressive black cherries, pignut hickories and silver maples. Tiny red spots on the pavement proved to be fallen flowers from the silver maples, which get an early start on spring.

Susy of the Whole Earth Center provided cider and cookies. There were nine of us, all told. Thanks to all!

-- These native plant workshops are sponsored by Friends of Princeton Open Space and the Whole Earth Center.

Wildlife Refuge Restoration Begins in Earnest

A misty morning at Rogers Wildlife Refuge in Princeton. This observation deck looks out on a great diversity of native plant and birdlife . The relatively dry ground the deck stands on, however, is dominated by invasive shrubs like multiflora rose, honeysuckle and privet.

This past Sunday, we cut these exotic shrubs at the base with loppers, covering about a half acre of territory in a couple hours. The marsh has few enough of these exotic shrubs that there's a chance we can cut them all down before spring, making more room for native species and greatly reducing the seed source these exotic fringe areas represent.

Thanks to Owen and Kathy for their help!

Restoring a Marsh

This past year, the Friends of Princeton Open Space received a grant from the federal government's Wildlife Habitat Incentive Program (WHIP) to restore four acres of habitat in Mountain Lakes Preserve. The initial phase of the restoration involves removing the intimidating architecture of invasive shrubs from the chosen locations in the preserve.

Recently, volunteer Michael Arntzenius and I took advantage of the cool winter weather to take on the dense growth of exotic multiflora rose, privet and shrub honeysuckles growing around a springfed marsh.

When confronting a ten foot-high wall of invasive shrubs, some of which are well-armed with thorns, one helpful motivation is the liberation of the native species partially buried in the invasive tide.


Here is a particularly satisfying situation, in which a native red chokeberry can be relieved of competition from the invasive multiflora rose growing up, through and over it (cluster of native stems to the left in photo). Just two strokes of the loppers shifts the balance, allowing the native to lay claim to sunlight and soil moisture in the coming growing season.






After some struggle, and a few encounters with the business end of the rose bushes' armor, we cleared a pathway along the edge of the marsh, which has remained hidden behind the thorny wall for decades.










Here's how the marsh looks in late May, with fringed sedge, skunk cabbage, winterberry thriving in the springfed opening. Per usual, the wettest areas are dominated by natives, with the exotics having the upper hand around the fringe.

2nd Workday At Mountain Lakes--More Progress

During the Sunday workday at Mountain Lakes on Feb. 10, we were treated to a command performance of rapid mood swings by the weather. Clouds gathered, then scattered, the wind roared through the treetops, then settled down; finally, snow began to fall, dusting the valley in white. Through all of this, we continued working down the small valley, pulling up the smaller invasive shrubs and cutting the bigger ones at the base, expanding on the work done the week prior. Some of the larger exotic shrubs--honeysuckles and privets--were left standing for later cutting into sections that can be used to "corduroy" the muddy trail running past the worksite. Thanks to Steven, Russ, Brownlee, Cynthia, Annarie and her daughter and son, and Kathy for all their help.

Habitat Restoration Update

Another habitat restoration session is planned for this Sunday, Feb. 10, at 2pm. To participate, drive up the driveway at 57 Mountain Ave in Princeton, and park in the gravel parking lot. Please wear work clothes, leather gloves, and bring tools if you have them. Bowsaws, loppers, pruning shears, clippers--any of these would be useful, though I have a few extras. Below is an account of what transpired last weekend.


This past Sunday's workday at Mountain Lakes was very productive. The "winter" weather (sunny, 45 degrees) and soft soil proved perfect for pulling out hundreds of small honeysuckle and privet shrubs that have been invading the valley.

We left the two or three native shrubs in the mix (red chokeberries), and noticed many sedges and a few Christmas ferns ready to respond to the new dose of sunshine they'll receive now that the invasives are removed. One not-too-invasive exotic, wineberry, was left in place, the idea being that we'll control it by eating its raspberry-like berries in the summer.





In this photo, the adults stand back as the kids take on an invasive honeysuckle shrub.

Native Plant Workshop, Sunday, Jan. 27

The first of the new year's series of monthly native plant workshops in Princeton will be this Sunday, January 27 at 2pm. We'll meet at the Community Park North parking lot (next to Pettoranello Gardens at Mountain Ave and 206), and walk up to Mountain Lakes House, doing some winter plant identification along the way. At the house, we'll have a planning session for the new year's field trips and initiatives, and take a look at the lakeside spot we planted last fall. The Whole Earth Center will provide cider. The workshops are open to the public.

Among initiatives are:

• Growing native wildflowers and grasses this spring from locally collected seed. Some can be grown at the Mountain Lakes greenhouse, but participants can also plant and care for a few flats in their backyards, use some of the plants and make the rest available for the workshop plant sale and local restoration projects.
• Start a native plant workshop listserve, for participants to post questions, info and ideas.
• Develop plant inventories for local preserves.
• Other initiatives participants suggest.

If the weather is inclement, come directly to the Mountain Lakes House at 57 Mountain Ave. There's a parking lot at the end of the long driveway.

The workshops are co-sponsored by Friends of Princeton Open Space (FOPOS) and the Whole Earth Center.

Public Library's Environmental Film Festival

Below is the link to info about the great film festival at the Princeton Public Library, in its second year, happening now through January 12. I'll be making a slide presentation entitled "Restoring Native Habitats In Princeton Preserves and Backyards" on Saturday, Jan. 12 at 1:30.

The 2008 Princeton Environmental Film Festival

Wednesday January 2 – Sunday January 6, and Saturday January 12

All screenings and talks are free and open to the public and are in the Community Room at the Princeton Public Library, 65 Witherspoon Street, Princeton, NJ.

COMPLETE SCHEDULE and more information: http://www.princetonlibrary.org/peff/

The Color-Coded Forest

Even this late in the fall, some shrubs and trees announce their identities by the colors of their leaves. They can appear as if a child carefully colored in a number-coded landscape-- oaks and blackhaw Viburnums bronze, the Asian photinia a golden yellow that turned to dark brown in the hard frost. Here is a photo of Pettoranello Gardens, with native oaks bronze above a shrub layer of still-green exotic honeysuckles.

The logic here is that the honeysuckles evolved in a milder climate on another continent, whereas plants native to America adapted to longer winters by dropping their leaves earlier.


Just upstream of Mountain Lakes, the extent of exotic invasive shrubs is especially revealed this time of year, as the vistas open up. The pink of winged Euonymus has just fallen, but the invasion of honeysuckle shrubs can easily be tracked by their persistent green.

A Norway Maple's Memory of Distant Lands

The frost hit hard two nights ago, as the temperature dipped to the low 20s. A full moon shone down from so nearly straight above, and so bright on a cold snap night that even a town slicker took notice. I went outside and in the stillness heard the floppy sound of Norway Maple leaves hitting the ground in a steady letting go. No other kind of tree was dropping its leaves--only the Norway Maples, still responding after centuries in America to cues and tempos learned long ago in distant lands.

Autumn's Backyard Dance Audition

Today, an Indian Summer day, with brightly colored light filling the backyard, I tried to make myself still enough to watch leaves fall.

The trees in my backyard are a mixed blessing. They obscure the sunsets and the vast sweep of the sky, but today they are offering their own endless permutations of beauty. Each leaf, huddled in vaulted obscurity all summer long, has but one chance to show its personality. Gliding back to the ground from whence they came, the leaves of a silver maple tree slice through the air, each in its own way. Some are in a rush; others stretch the moment for all it's worth. Some spin fast, some slow, some descend in spirals tight or broad. Others glide like well-crafted paper airplanes, landing far afield. Each catches the light in this moment of distinction, these few seconds of quiet fame.

As if they were dancers auditioning for a ballet that will be forever in the writing, I wish I could congratulate each one on its flight--its contribution to the beauty of an autumn day--before it fades beneath a shimmering shower of countless others.

Ivy Control, Part 2

A typical scene along a property line, where English Ivy has taken over. Say you tire of its imperialistic ambitions and static green, but don't want to engage in a down and dirty tug of war (see previous post, 3/5/07). If it happens to be fall, and leaves are plentiful, it's a perfect time to do it in without hardly a pull.



Enter that most versatile of substances, cardboard, easily requisitioned along curbsides. The bigger the pieces, the better. Some people use newspapers, but many layers are needed, they decompose too fast, and their small size makes for many more cracks where the ivy could push up. Tools needed are shown.

The principal behind this approach involves the need of plants for energy. Cut off sunlight for months at a time, and even a powerful-looking patch of ivy will fade back into the ground. With a constant need to metabolize, and no new energy coming in, the ivy roots die of starvation.

Use this approach only if there are no spring bulbs or other desired plants mixed in with the ivy.

Begin by pulling the ivy away from trees and shrubs. If it's rained recently and the ground is soft, most stems pull easily out of the ground. Cut the stubborn ones with hand clippers. Also work along the edges of the patch, pulling the ivy back to reduce the area that needs to be covered.



Then spread the cardboard, overlapping 6" to a foot to prevent any ivy from pushing up through gaps. Where there are lots of shrubs to work around, and different sizes of cardboard to work with, it starts to feel like a jigsaw puzzle, finding the right piece to fit any particular spot. In these photos, the process is simplified because the shrubs are all in a line.



Be sure to cover all the ivy, or sever connections between the areas covered and those that will remain exposed. Otherwise, the ivy that doesn't get covered will continue sending energy to the ivy under the cardboard.



Now it's time to cover the whole thing up with leaves, giving the impression that there is no ivy or cardboard. Over, say, two to six months, the ivy will give up the ghost, the cardboard will decompose and the area can be planted with wildflowers, bulbs, what have you. In the meantime, the leaves provide a quiet, woodsy feel. This whole project took about two hours.

Potts Park Update

Heavy rains have slowed installation of new play equipment at Potts Park, the little pocket park that time almost forgot and most Princetonians don't know exists.

















Construction vehicles were trapped in high water, causing further delays. Bob the Builder says he's doing everything he can to get the project back on track.















Meanwhile, a small, climbable forest has been planted on the south side of the park, and is expected to grow in fun potential over the next few days.

October's Native Plant Workshop--Plants in the Ground

This past Sunday's workshop featured a tour of habitat restoration projects sprouting along the edge of Pettoranello Gardens, followed by a planting session next to the upper Mountain Lake. We had gorgeous weather and lots of wildflowers to put in the ground--all grown from locally collected seed in order to preserve whatever traits the local genotypes may have to offer.

Hibiscus, swamp milkweed, cutleaf coneflower, sneezeweed (it doesn't make you sneeze) and woodgrass (actually a sedge) were planted in full sun along the water's edge and marked by stakes and string to protect them from accidental mowing.

With some luck, Mountain Lakes offerings for pollinators next year will be markedly improved.

Thanks to all who came and enjoyed the weather, each other's company, cider and cookies provided by Whole Earth Center, and the satisfaction of making a glorious setting even more so.

Native Plant Workshop, Sept. 23, 2pm

At this month's 4th Sunday installment of the Native Plant Workshop, to which all are welcome, we’ll discuss two new initiatives. One is to collect seed of native species this fall, for growing seedlings next spring. The other is to organize and train volunteers to inventory plant life in Princeton’s parks and preserves, for inclusion in an Environmental Resource Inventory being prepared this year.

Following the discussion, we’ll head to Rogers Refuge (photo), a birding mecca below the Institute Woods, where an “accidental” man-made marsh hosts 100 species of plants. This time of year, redwinged blackbirds are gobbling down wild rice, and blooms can still be seen of pickerelweed and tickseed sunflower. No boots necessary, since we'll stick to gravel roads and the observation tower.

Meet at the Whole Earth Center in Princeton, at 360 Nassau Street.

The workshops are sponsored by Friends of Princeton Open Space and the Whole Earth Center.

Tickseed Sunflower Along Quakerbridge Road

Take a drive out towards Route 1 on Quaker Road and you'll find the roadside near the canal filled with bright yellow. Though goldenrod plays a part, the chief protagonist is tickseed sunflower. Unlike the many species of native perennial sunflower, this one's an annual, in the genus Bidens.



Bidens was one of the showiest wildflowers along bike trails when I lived in Durham, NC, and though I'd lived here in Princeton for four years, I had yet to see it growing here in abundance until I turned the corner on Quaker Bridge Road and saw it stretching out across a broad field.








This photo was taken a few days past full bloom, but halfway out into the field was a bright yellow world teaming with monarch butterflies bouncing from sunflower to sunflower. The butterflies are by now making the long journey to a hilltop in Mexico for the winter, and the Bidens are making seeds for next year's Really Big Show.

Princeton Freshmen Take On Ailanthus

There's a bench at Turning Basin Park in Princeton, located strategically on a bluff overlooking the canal. Nice view, except that the canal could not be seen due to a wall of Tree of Heaven sprouts that had grown up in front of the bench.

This past Friday, the view of the canal was restored, thanks to a workday organized by Princeton WaterWatch and Butler College. While a couple picnicked on the bench, 25 Princeton University freshmen came down to the canal and cleared the Tree of Heaven (Ailanthus) from the slope between Turning Basin Park and the canal. I gave them an introductory spiel about the role of Friends of Princeton Open Space in town and the value of doing habitat restoration.

Though most had arrived with little knowledge of plants, they soon found themselves vigorously taking on Princeton's most invasive tree. While clearing the view for the one bench, they found another that had disappeared completely beneath the swarming invasive growth (on the left in the photo). A highly invasive vine, Porcelain Berry, was also cut along the slope. Any resprouts next year should be considerably weaker, since cutting them this time of year will cheat their roots of any nutrients the leaves and stems would have sent down in preparation for winter.



The view of the canal restored (the couple were comically oblivious to our efforts), the students then treated themselves to canoe rides. All in all a fun and rewarding afternoon.

PDS Student Make a Difference at Mountain Lakes

Mountain Lakes, part of 400 acres of preserved land between 206 and the Great Road, is a popular hiking spot for Princetonians. Home base of the Friends of Princeton Open Space, its habitat is in great need of ecological restoration.

On September 7, 100 Princeton Day School freshmen and accompanying faculty arrived at Mountain Lakes for their second annual community workday. PDS has informally adopted the area in the upper right of the photo, stretching upstream along the two creeks that feed the lakes.


Using loppers, the students broke up into workgroups and took on the thorny multiflora rose that has displaced native species from floodplains in Princeton, as it has all over the eastern U.S.

Two hours later, large piles of the cut invasive rose were amassed in the woods, and native species like blackhaw Viburnum, sassafras and spicebush suddenly had more room to grow.

The students showed great perseverance and teamwork in achieving an impressive transformation of the landscape.

Here, two students push the thorny shrub's branches out of the way with garden rakes, allowing another student to reach in and cut the stems at the base with loppers.

After lunch, the students returned to learn more about the ecological forces at work in the preserve.

During the past couple Aprils, the ENACT environmental group from PDS, led by Liz Cutler, has also come to Mountain Lakes to help with invasive species control.

Thanks to all the students for their hard work. And thanks to Mark Widmer for coming by to take photos.

Scout Restores Lost Trail in Community Park North

Stray into the woods behind Pettoranello Gardens, across 206 from the Community Park soccer fields, and you may wonder if you've happened upon ruins of an ancient civilization lost in the overgrowth. Strange towers rise out of the thickets, and improbably massive picnic tables lay half-sunken in the dirt. Markers reveal the identity of various trees, suggesting a nature trail once meandered through this forgotten landscape.

Old rec dept. maps show that trails did in fact once traverse this area, but most disappeared beneath the invasion of exotic shrubs over the past couple decades. Multiflora rose silently covered this land in a Sleeping Beauty-like shroud of thorns.

Then along came Harald Zurakowski, Princeton resident, seeking an eagle scout project. With help from the Friends of Princeton Open Space and the township, Harald planned his project, then mobilized family and friends over the Labor Day weekend to reblaze lost trails and make this place hospitable once again for hikers and native species.


Harald poses in front of one of the Long-Buried Climbing Towers of Community Park North.

















This is a "before" shot, showing the intimidating thicket of multiflora rose, privet and shrub honeysuckle that Harald and friends took on with nothing more than handtools and grit. The goal was to create a viewscape in towards Pettoranello Pond from higher ground nearby.







In the process, they created access to a rocky creek next to Pettoranello Gardens.












After the viewscape was successfully cleared, they planted native wildflowers and ferns provided by Mapleton Nurseries. A few native shrubs--silky dogwood and spicebush--were spared during the clearing.

Prairie at Bowman Hills Wildflower Preserve

One of the finest examples of native grassland in the area can be found at the entry to Bowman Hills Wildflower Preserve, along the Pennsylvania side of the Delaware River. I stopped by last Friday, while driving from Washington Crossing to New Hope, and found it in full bloom. The photo shows Wild Senna, which likes the wetter soils at the bottom of the slope. All the classic prairie grasses can be found here: Big Bluestem, Little Bluestem, Indian Grass and Switchgrass. The Big Bluestem--the dominant grass of the tallgrass prairies of the midwest--are eight feet high.

In Princeton, the most likely place for future native grasslands to be planted is in the retention basins at local parks. One such project is underway at Farm View Fields, with help from Partners for Fish and Wildlife.

Indian Grass is the most common warm-season prairie grass to be found in the area. It needs sun, so likes areas that are mowed yearly, such as roadsides and right of ways. The anthers give it a golden tint this time of year. Back in pre-colonial times, it would have been munched on by buffalo, whose range once extended to the east coast.

Wild Rice at Rogers Refuge

One of the more spectacular sights this time of year in Princeton is the wild rice blooming at the Rogers Wildlife Refuge. Though sometimes called "the Institute Pond", the refuge is actually located on water company property. A giant step towards restoration of the marsh was taken last year when Partners for Fish and Wildlife treated the invasive giant Phragmitis reeds that were slowly but surely taking over the marsh. Quickly taking the place of the Phragmitis monoculture is an impressive array of natives, including the wild rice, pickerel weed, arrow arum and water plantain. The refuge lies between the Institute Woods and Stony Brook, at the end of West Drive. It's best known as a birding mecca, and is taken care of through a collaboration between Friends of Rogers Refuge (FORR), the township and the water company. To get there, take Alexander Road down almost to the canal, turn right on West Drive and stay left until you reach the small parking area next to the observation tower.




Wild rice, like corn, is an annual that grows to astonishing heights in a single season. Most people associate it with Minnesota, but it flourishes in Princeton, the Trenton Marsh, along the Connecticut River, and I've even seen it growing in a stream in Florida.

Canal Towpath Walk on Saturday, August 11, 10am

Many of the showiest wildflowers along the canal in Princeton bloom this time of year. I'll be leading a walk along the towpath this Saturday, August 11, at 10am, starting where the towpath crosses Washington Road in Princeton. There's a parking lot next to Washington Rd. just south of Carnegie Lake and the canal, where a service drive heads up to the university's ballfields. If you get there late, we'll be heading eastward along the towpath, towards Harrison Street.

The land along the canal hosts a remarkable diversity of native wildflowers, thanks to its combination of sunny openings and moist ground. The reduced mowing regime instituted last year by the D&R Greenway State Park has allowed many previously suppressed species to flower and spread.

The walk is sponsored by the Friends of Princeton Open Space.

(The photo is of Purple-Headed Sneezeweed, named of course for its reddish brown center, yellow petals, and general lack of sneeziness)

INVASIVE ALERT--Mile-a-Minute in Princeton!!

A new invasive plant has made its way to Princeton. While passing by on a bicycle, I found it growing next to a driveway within sight of the Princeton Shopping Center. It's triangular leaves and curved spines are unmistakeable. "Mile-a-Minute" is it's name--appropriate given its rate of growth.
I'll add to this post when I find out where else it's been found, whether it's officially listed as a noxious plant in NJ, and any details about what to do if you find it. In the meantime, keep an eye out for it. If you find it, let me know, and if it's on your property pull it out!

Update, 3/2011: After stopping by several times to knock on the door, I finally met the homeowner, who was glad to get rid of the weed. We pulled it out before it could make seeds, and haven't seen it since.

Canal Wildflower Bonanza

This is the start of prime time along the canal. The area I walk is just west of Harrison Street. All the classic floodplain wildflowers are blooming. Just finishing up are tall meadow rue, lizard's tail and buttonbush (white flowers), and purple-headed sneezeweed (yellow). Just coming on is the small forest of cutleaf coneflowers (yellow) that grow up to 8 feet high. Though fewer in numbers, you may see JoePyeWeed, swamp milkweed, and fringed loosestrife.
The purple spires, mostly along the canal, are purple loosestrife, a highly invasive exotic. Tyrol knapweed, also an exotic, has violet flowers.
The blackberries are abundant and ripe, and shrubs like elderberry, Arrowwood Viburnum (photo) and silky dogwood are heavy with ripening berries for the birds.

Some Canal Wildflowers

Tall Meadow Rue -- One of the many native species that thrives in sunny, wet areas, of which there are few in Princeton.








Swamp Rose--This is the native rose, found growing on the banks of Lake Carnegie and the canal.






Crown Vetch--This is an invasive exotic groundcover. It used to be planted along highways, before its invasiveness was recognized. It's common along highway 76 in Pennsylvania, and also pops up in Princeton here and there.











St. JohnsWort

Late June Wildflowers Along the Towpath

(You can type any of these names into an internet search engine to find info)


Tall Meadow Rue
St. John's Wort
Silky Dogwood (fading)
Elderberry (shrub; berries good for making jelly, if the birds don't get them first)
Daisy Fleabane (very common)
Purple-Headed Sneezeweed (just opening)
Purple Loosestrife (invasive exotic--fortunately not too many thus far)
Swamp Rose (the native rose, with a pink flower, as opposed to the exotic multflora rose)
Lizard's Tail (grows at edge of Carnegie Lake)

Wetland Garden Plants Get Upscale Digs

300 native wetland wildflowers and sedges were relieved of oppressive crowding this past Sunday by Native Plant Workshop volunteers. Each of the plants--rose mallow, swamp milkweed, cutleaf coneflower, woolgrass and the infamously named Purple Headed Sneezeweed (it has yellow flowers and doesn't make you sneeze)--now has its own root space to grow through the summer. They'll be camping out in these containers, protected from squirrels by hardware cloth, until they can fill vacancies this fall in local wetlands and floodplains such as at Mountain Lakes Preserve. The plants were grown from locally collected seed, as a way of preserving whatever might be special about the local genotypes. Thanks to Valerie and Lynne for their help.