How sunny is the space? Is wax myrtle hardy for you? If so, is it evergreen? Would you consider a mixed screen?

Remember, benefiting wildlife isn't just about berries. Many birds need insects, so consider plants that attract insects.

Here is a link that might be useful: top 20 plants for caterpillars

@esh - I have 15 out of the 20 perennials on my property (I've used Tallamy's guide since the start of my project) so I'm not as concerned about that. My problem is that I've concentrated so much on how many host species each plant can support and didn't pay as much attention to design.

Out of all the plants I've considered over the years, I've never considered a wax myrtle. I'll have to look into it more. I would definitely consider a mixed screen. If it were you and you had that 20' strip, how many myrtles and how many viburnum would you plant and in what arrangement?

That's why I've never heard of it -- out of its range. I'd have to go with the northern bayberry, Myrica pensylvanica.

Northern bayberry is nice but I haven't seen it get very big, at least in my zone. It also tends to be a bit bare where the fruit form. Would definitely recommend it for other uses in the landscape.

I planted a privacy screen once that consisted of American highbush cranberry, eastern ninebark, american filbert, and blackhaw viburnum. Of those american filbert worked the best but would likely get too big for your space. The blackhaw and highbush cranberry worked quite well and produced nice flowers in the spring, fruit in the summer/fall and sometimes nice red fall color. They can get pretty big (though there are dwarf cultivars of the highbush cran), so I'd estimate planting 4 feet apart at a minimum.

Oakleaf hydrangea is also nice if it gets plenty of sun, but tends to be quite sparse in the winter. I've seen it used in hedgerows at zoos and botanical gardens. Nice flowers and reddish fall color.

If your soil is acidic and has good drainage you might consider mountain laurel or Catawba rhododendron.

If it were you and you had that 20' strip, how many myrtles and how many viburnum would you plant and in what arrangement?

Probably only two myrtles (and you'll want females) and then the rest viburnum. Is Viburnum rufidulum in your range? That has prettier leaves, I think. You could mix the two of them.

Other ideas for full sun are Beautyberry (mockingbirds love the berries) and Aronia (now with a new name).

Lots of good info and many options to consider. Really liked that wax myrtle til I found out I was out of its northern range. I'll probably pick some combination of things mentioned... but what about a pawpaw patch?

Esh, if you're referring to Aronia being placed in the genus Photinia, there were a couple of papers published in 2007 that provided evidence for rejecting that change. I'm not aware of any subsequent studies.

lycopus, really? That would be great. Any idea why USDA plants database not accept that rejection? They changed their names and Aronia is now just listed as a synonym.

I think the USDA is behind the times, perhaps due to budget cuts or maybe they just don't keep on top of changes in nomenclature. I just took a quick look at how they classify the families Scrophulariaceae and Orobanchaceae and it appears they haven't adopted many of the changes that have been proposed over the last decade. They might just be waiting until the Flora of North America publishes those treatments.

c2g:

Pardon my asking, but where do you garden? Zone 6 covers a multitude of bases - including me. It'll help home in on appropriate species.

If you are after year-round screening, having something or two that is evergreen will assist. You should consider American Holly (Ilex opaca) at least. You also might think about Magnolia virginiana var. australis as well. Both - with a bit of pruning - can have ample density of foliage to screen out that Prius/garage.

You haven't said, but how much more turf are you willing to part with along that edge? If you can unify the bedding with the Populus clump, then something like Viburnum prunifolium will fit. I reckon you are aware that Blackhaw Viburnum has no trouble reaching 20'x20'?

Additional plants to extend your seasons of interest, bird attractiveness, and screenability: various shrubby dogwoods like Cornus amomum and Cornus racemosa; a dense stemmy Viburnum dentatum mass; and even a heavily winter-fruited Winterberry like Ilex verticillata 'Winter Red'.

Finally, you could dog it with an incredibly marcescent big shrub like Hamamelis vernalis - and come out smelling like a champ.

@viburnum - I live in Philadelphia.

For whatever reason, I'm not too fond of American Holly.

One day my entire yard will be a planting bed, but for now I have two small children and a swing set right next to that bunch of quaking aspen. The blackhaw option is seeming to be more trouble than its worth since I'd rather go with something that doesn't require pruning.

I have a sweetbay magnolia in another area of the yard as well as two ilex, which unfortunately happen to be of the same sex, so no fruit set and they've been really slow getting established since I planted them a few years back.

I'm going to look into the shrubby dogwood option a bit more. I have a cornus florida 'cherokee brave' on the other side of the yard that gets a fair share of bird action.

Wish I was in the range of wax myrtle. All the other evergreen shrubs I like are either too big for the space, or they're trees. I'll sacrifice the winter privacy of an evergreen for something somewhat densely twiggy and flowering.

I like witch hazel, but I believe I read that they're of limited value to wildlife.

What about Ilex glabra? It's a slow grower but it's evergreen, stays a modest size, and produces berries for the birds. And doesn't look anything like opaca. : )

Also, any thoughts about Mountain Laurel? If your soil is acidic enough, some of the cultivars don't get as big as the wild Kalmia. Like 3 to 4 feet max.

Mountain laurel is a definite posibility. My property is packed with a little bit of everything, and my instinct is to fill that row with a mountain laurel on the left, which would get most of the shade from the maple above it; and then some combination of 2 or 3 gray dogwoods and a blackhaw viburnum (saw that combo on another post in the wildlife gardening forum). Plan on some pruning until the kids get bigger at which point I get rid of the swing and 90% of the lawn and go for a completely naturalized look. Does that make sense from a design perspective, or is it crazy talk?