During the past several weeks, the woods behind my house were inhabited by a flock of fifty or more robins. These birds didn’t visit my seed feeders though they happily used the heated birdbath many times over during the day. This is the most robins I’ve ever seen during the winter, and it made me wonder what possibly brought them here and what food they are utilizing. I knew they were finding purple berries of some sort since they were leaving remnants of these under the bird bath!
It turns out that winter flocks of robins are not uncommon. They eat both worms and insects as well as fruits during the summer, but they become solely fruit-eaters in the winter. I think this flock was feeding on the berries of the invasive English ivy that is growing up some of the trees, but there may be some fruits left on the native hackberry trees and virburnums in the woods as well. Evidently these nomadic flocks move into an area, deplete the fruits remaining on the vegetation and then move on to a new site. In fact, they are much less visible from my windows today so I suppose they’ve had their fill of this area!
If you want to help the birds in your yard during those harsh winter months, there are a number of native shrubs and trees that will help provide food as well as shelter in the winter. Emelie posted about the wonderful winterberry hollies (Ilex verticillata) on this blog about a month ago. Another set of shrubs which add winter interest are the Red and Black Chokeberries (Aronia arbutifolia and Aronia melanocarpa ). I just planted several Aronia arbutifolia ‘Brilliantissima” this past fall. This 6 to 10 foot deciduous shrub produces loads of small white flower clusters in spring, and these are attractive to early pollinators. The bright red fruits begin to mature in September, and the fall foliage is vivid red as well. In fact, it is considered an excellent native replacement for the invasive burning bush! The fruits, though edible, are quite bitter, so birds don’t eat them until they’ve undergone several freeze thaw cycles in the winter. Thus they persist like the winterberries providing both winter food as well as color! By the way, the red chokeberry is not the same plant as the common chokecherry, Prunus virginiana.
The black chokeberry, A. melanocarpa, is smaller (3-5 feet tall) and has several named varieties such as ‘Autumn Magic’ and ‘Iroquois Beauty’ that are supposed to be more ornamental than the species. It produces white flower clusters in spring and pretty purple/red fall foliage. Its black berries also persist into winter due to their bitter flavor. The fruits of both plants are high in vitamin C and antioxidants and can be used to make juice, jellies, jams and pies if you prefer not to share them with the birds! Both shrubs prefer sunny areas and moist soil where they tend to spread by suckers, although they are not fussy plants and will tolerate drought and various soil conditions. They can become leggy so they are better suited to growing in mass in naturalized areas with other native shrubs rather than as specimens or in formal shrub borders.
There are a number of other species that you can research if you’d like to add some fall and winter food species to provide food for the birds. These include some of the viburnums especially V. trilobum, V. dentatum and V. nudum, as well as hawthorns, crabapples, staghorn sumacs, Eastern red cedar, beauty berries, northern bayberry and some of the dogwoods. Here is a link to a Penn State fact sheet that will give you more information: