Friday, May 19, 2023

Documenting the PHS Ecolab's Recovery From Last Year's Trauma

Passerby on Walnut Street may have noticed that the Princeton High School Ecolab wetland was completely stripped of vegetation by an outside contractor this past November. After the shock of having so many native shrubs and wildflowers suddenly gone, it took us awhile to realize that the roots of the native plants might still be alive beneath the bare dirt. Having lobbied successfully to have stewardship of the Ecolab returned to the teachers, students, and volunteers who had cared for it free of charge for fifteen years, we are watching for signs of its rebirth. 

Most obvious is the annual grass planted by the contractor for erosion control. But I took a closer look and found gratifying evidence that the wetland will rebound. Click on "Read more" below to see a photo inventory of 40 native species (and a few very manageable weeds) that have popped up thus far, ready to refoliate this wonderful teaching resource for the school's environmental science program.

The weeds are truly modest--a little bit of white clover,
one ragwort (a weedy native), 

a willow oak (native, but all trees need to be pulled out, given the proximity of buildings).
Among the plants worth keeping, there's a native wild strawberry, 
Indian hemp getting ready to bloom,
tall meadowrue

Only one tiny winged euonymus, easily pulled.
Just a few multiflora rose to be dug out.
An ash tree to be pulled or cut (no trees allowed!).
Common milkweed
Late-flowering thoroughwort--a late-season wildflower that can sometimes look weedy, sometimes elegant.
Either dandelion or curly dock.
One of my favorite native sedges, fringed sedge, whose tough roots make it a good choice for stream restorations.
Buttonbush, working on generating those pretty golfball-sized clusters of flowers that bumblebees love.
A native Hibiscus moscheutos--the biggest flowers in the basin.
Great to see pickerelweed coming back. It has blue flowers through the summer.

Marsh marigold--a very rarely seen native wildflower
Black cherry growing out of a wall needs to be pulled so its roots don't hurt the wall.
Looks grassy, but is actually a sedge.
This too looks grassy, but is actually blue flag iris, also rarely seen in the wild.
Joe Pye Weed is coming back here and there.
The tiny leaves are a non-native aquatic plant. 
Not sure what this is.
Boneset, good. Growing out of the wall, not so good.
Virginia creeper is a native vine, but can get rambunctious. 

Evidence that an environmental science class has been weeding out thin-leaved cattail, leaving some in the distance for now.
Thin-leaved cattail is a native, but spreads aggressively underground. 

Maybe enchanter's nightshade, with a name scarier than the plant itself.
Sensitive fern is no slouch. It can spread in wet areas to form attractive mini-groves.
Lizard's tail is another native that's rebounding well.
Bidens is an annual native. Some species are very showy, like sunflowers, others not.
Good old jewelweed, a native annual with tubular orange flowers all summer that the hummingbirds like.
A polygonum (smartweed). May become problematic if desired plants don't grow over it to limit its spread.
The native swamp rose I put in long ago is resprouting.
Equisetum spreads over the ground. 
Ironweed--another pretty, tall wildflower of wet meadows.
Cutleaf coneflower
Lots of elderberry shrubs popping up.
The stump of a sycamore is sprouting. Again, no trees! Especially those sprouting from the wall.

A native sunflower. These spread aggressively underground, but could be held in check if surrounded by shrubs that shade them out.
Poison ivy--best get that early.
An oak, asiatic bittersweet vine, and wild grape. Probably should weed all of these out.

Good to see the silky dogwoods coming back. 

Native cup plant gets impressively big.

Duck potato--a keeper.

Blackhaw Viburnum is coming back, too.
The one native wildflower whose seeds are sprouting prolifically is wild senna.

Happy not to see any stiltgrass popping up. Will need to keep an eye out for it though. One nice thing about the Ecolab is that it's isolated, so weeds that are ubiquitous elsewhere are less likely to find their way here.


  1. Laurie Larson5/23/2023 12:33 PM

    Duck potato! Wonderful name. I know it as arrowhead. Thanks for this fascinating post, Steve.

  2. Can offer American groundnut tubers, Erigeron seedlings, Tragopogon pratensis, more blue species Iris, even a Sisyrhinchium (sp?) in bloom. Let me know.