From http://nativeplantwildlifegarden.com/plant-this-not-that-shade-plants-for-suburbanurban-woodland-buffers/?utm_content=buffer230fe&utm_medium=social&utm_source=facebook.com&utm_campaign=buffer
The exotic (non-native)
Japanese Pachysandra (
Pachysandra terminalis),
periwinkle (
Vinca minor),
English ivy (
Hedera helix) and
Wintercreeper (
Euonymus fortunei)
have long been staples of New England gardens for their shade tolerance
and ground covering habit. Go to any garden club sale or plant swap in
the spring and you’ll find these plants available by the bucketload —
but if you live in the northeast US and have a bit of woods separating
your property from your neighbors, think twice before bringing any of
these plants home.
Vinca
minor forms mats under trees, but can spread into nearby woods if not
contained or blocked with edging or walkways. This small wooded buffer
in Boston’s suburbs is completely covered with vinca which has crowded
out the lady’s slippers, lowbush blueberries and solomon’s seal which
once grew here.
Because
these plants spread aggressively by their roots or stems, when they are
planted adjacent to moist woods in New England, they can quickly spread
into the woodlands, choking out anything else that happens to be
growing there and threatening unique and fragile woodland plant
communities. English ivy and Wintercreeper also climb trees and can
eventually kill them (not to mention the damage the ivy can do to your
house if you allow it to climb walls).
And once these plants are established in an area to their liking,
good luck getting rid of them if you ever decide you’d like to plant
anything else! Pictured below is a small woodland buffer in Sudbury, MA,
highly valued by the homeowner for its summertime privacy screening
from neighbors. The vinca, pachysandra and English ivy planted decades
ago near the house have escaped into the woods and the homeowner is
frustrated that the young trees are dying, and that she cannot get seem
to get any other plants established here:
This
client opted for professional removal of the invasive plants using a
mixture of low-impact (non-herbicidal) removal methods and looks forward
to establishing a woodland garden with plants such as trilliums,
bugbane, wild phlox, baneberry, wild ginger and ferns.
If you drive around the leafy outskirts of Boston MA, you might be
impressed at the established trees, especially in older neighborhoods
(more than 50 years old). Many of the spaces between houses are heavily
wooded — in New England, trees don’t need much encouragement to grow.
But take a closer look at what else is growing under those trees. You’ll
quickly notice those same few species of plants in just about every
neighborhood!
You won’t see these plants on New England state invasive plants
prohibition lists, simply because they don’t reseed themselves the way
invasives such as
Asiatic bittersweet do — by birds
eating and dispersing their berries far and wide. They spread mostly
from being planted in favorable conditions near moist woodlands. As so
much of our region is now gobbled up by roads and development, those
wooded buffers between homes are often the only wildlife habitat that
remains in metropolitan areas of the northeast. Although birds might
utilize the trees for their nesting opportunities and insect forage, a
buffer taken over by invasives will lack most of the ecological benefits
provided by a diverse understory of native woodland plants. For
homeowners that understand that their yard plantings have an impact on
the wider environment, a little effort to search out appropriate native
plants will go a long way towards increasing the biodiversity and
wildlife value of suburban yards. Not to mention, the results are much
more interesting!
Woodland garden at New England Wild Flower Society’s Garden in the Woods in Framingham, MA.
So, if you do border on moist woodlands, what are some “safe”
alternative groundcover native plants to look for? Try the beautiful
running foamflower (
Tiarella cordifolia), which is (mostly) evergreen and forms a thick weed-suppressing mat under trees:
There is also a native pachysandra called Allegheny Spurge (Pachysandra procumbens)
that hails from the southeast US, but grows happily in my zone 5
central Massachusetts garden. It looks a lot like Japanese pachysandra
but its leaves are less glossy:
Early
season foliage of allegheny spurge is bright and green, and later in
the season turns to a mottled pattern. It is not evergreen in my Zone 5
Massachusetts garden.
Canada Yew (
Taxus canadensis) is a native
yew that loves the cool, damp shade of New England forests. Unlike its
popular Eurasian cousins that are standard as sheared foundation shrubs
in the US (
T.cuspidata, T. baccata, T. x media), this yew stays low (2-3′) and spreads up to 10′ from its base:
Canada
yew growing along a stream at Turkey Hill Brook Farm in Spencer, MA. It
loves the cool damp microclimate of this forested north-facing valley
slope.
Because it’s a deer favorite, wild populations of Canada yew are
becoming rarer in Massachusetts, as suburbia pushes outwards and deer
populations soar out of control. Unlike other conifers, however, Canada
yew will resprout after being pruned (by deer or hedge-clipper), so if
you live where deer populations are somewhat under control (or you are
willing to put up deer fencing), the evergreen Canada yew is worth
growing to help preserve local populations and genotypes.
Wild ginger (Asarum canadense) is another
native that will quickly cover an area in moist shade. It’s growing here
at Garden in the Woods along with several types of fern and Allegheny
Skullcap (Scutellaria serrata).
More native eastern ground covers suitable for moist shade include
bunchberry and
mayapple:
I don’t believe Japanese pachysandra
or Vinca will disappear from our home landscapes any time soon, and
admittedly, as long as they are contained, they should not cause much
harm. A patch CAN be useful if you have dogs. Our border collie Speck
hates the heat of summer and loves to cool off in pachysandra, which
appears to bring him much relief. I have left one well-contained patch
as his personal dog bed…
Maryland’s
Wild Acres is a voluntary program which encourages Maryland citizens to
create backyard wildlife habitat. Backyard wildlife habitat can
increase food and shelter for wildlife, control soil erosion, reduce
sediment in waterways, conserve water, improve water quality, inspire
stewardship and beautify the landscape. The goal of the Wild Acres
program is to create backyard habitats across the State that maximize
wildlife benefits and highlight conservation stewardship. Backyard
wildlife habitat can include decks, yards, large lots and everything in
between. The Wild Acres program offers fact sheets on how landowners can
enhance their habitat for wildlife by creating food, water and shelter
resources. In addition to providing fact sheets, a quarterly
publication, Habi-Chat,
is produced which highlights native plants, animals and
habitat-enhancing activities. While the Wild Acres certification program
does not exist anymore, homeowners can still use Wild Acres information
to enhance their habitats. You can certify wildlife habitat through the
National Wildlife Federation and/or the Maryland BayWise program. 
Common Backyard Herps
