Replacements for Nandina and other learnings

Recently I wrote an article for Houzz on plants to use instead of Nandina domestica, aka Heavenly Bamboo or Sacred Bamboo.  This overused Asian species is adaptable to a wide range of growing conditions in USDA zones 7-9 and has reached invasive status in the Southeastern US.  In Maryland it is listed as a Tier 2 invasive plant meaning that, while it can still be sold in Maryland, it must be accompanied by signage stating that this is problematic species. 

What to Plant Instead of Heavenly Bamboo

In addition to its invasive characteristics, the bright red berries so prominent in winter are actually quite toxic to over-wintering birds.  The cedar waxwing is particularly susceptible due to their feeding behavior.  Blue Jays and Mocking birds are examples of other species that are at risk from this shrub.

You can read more about the toxicity of Nandina berries to birds in this post from Audubon Arkansas. You can mitigate this problem somewhat by planting more plants that bear fruit late in the season, particularly native species; but, you should not consider Nandinas as wildlife-friendly plants. If you want to use Nandinas for aesthetic purposes consider cultivars that do not produce berries such as 'Nana', 'Nana Purpurea', 'Atropurpurea Nana', or 'Gulf Stream.' These non-bearing cultivars are also less likely to spread outside the garden.

One of the species that I recommended in this article is Oregon Grape, Mahonia aquifolium, and other members of the genus.  This broadleaf evergreen shrub is native to the Pacific Northwest, but is also found growing wild in some eastern states, most likely as a garden escapee.  I thought I had some growing in my backyard, too.  While researching this species I discovered that what I had was, in fact, Mahonia bealei, Leatherleaf Mahonia.  This species, originally from western China, is listed as invasive in many of the same states as Nandina.   

Here are two Leathrleaf Mahonia growing in a clump in late January. 
This species of shrub typically grows 4-10' in height,
compared to 3-6' for the Northwest native Oregon grape.

The bright yellow flowers of Leatherleaf Mahonia bloom in late winter to early spring
on clusters of terminal racemes.  This species can be distinguished from Oregon Grape,
M. aquifolium, by the number of leaflets, 9-15 vs. 5-9, for Oregon grape. 
Also the leaf color of leatherleaf mahonia is a dull bluish green compared to
the shinier dark green leaves of Oregon grape.

Learning that what I thought was Oregon Grape was actually a non-native species with invasive tendencies, I've decided to replace it with species native to this area.  Even before this revelation I was considering replacing it with a more appropriate East Coast species.  I would like to have an evergreen shrub that likes moist soils and open shade.  Looking at my list of Nandina replacements for inspiration, I think I will go with Inkberry Holly, Ilex glabra, as the replacement. As with most hollies I will need both a male and a female plant to get berries for the birds.  Fortunately there are both male and female cultivars available in the nursery trade so I will be able to start an inkberry family without too much trouble.  As the male I will go with 'Nordic', a fairly compact species.  There are more choices for the female.  I would like them to grow to about 6 feet, so I have a choice of 'Compacta', 'Densa' or 'Nigra'.

This inkberry is part of a new parking lot planting at a local library
that features mostly native species.  It does well in part to full sunlight. 
My site may be on the shady side, but that may encourage
a more open form that I would like for my particular application.