The Truth about Nandinas Killing Birds

Nandina ‘Burgundy Wine’ along the front of my house – in January. Other evergreens are Osmanthus ‘Goshiki’ and Carex ‘Ice Dance’.

I recently welcomed visitors to my townhouse garden, happily at first, until I was asked – more than once – to defend the Nandinas shrubs I’d planted along the foundation. The visitors had heard or read something about cedar waxwings being fatally poisoned by Nandina berries.

Here’s a closer view of the accused Nandinas, with gorgeous winter color when my garden is at its worst, but NO BERRIES.  Yet to my accusers, cultivar/schmultivar, berries or no berries, the homeowner (me) has to answer for herself!

So in my defense (and you all know what fun it is to have to defend yourself) I turned to the most knowledgeable people I could find online, starting with the Garden Professors Facebook group. There Don Shor summarized the (apparently) sole report of such a poisoning: of cedar waxwings in Georgia found dead in 2009, five of them with their bellies full of Nandina berries, which contain cyanide and can indeed be fatal if enough are consumed. Audubon Societies and other groups were quick to tell us to remove it from our yards, or at least remove the berries.

Shor presents the facts he’s uncovered:

“Other birds don’t eat as much or as rapidly as cedar waxwings,” said Rhiannon Crain, project leader for the Habitat Network with The Nature Conservancy and Cornell Lab of Ornithology…Cedar waxwings completely stuff every possible part of their body with berries. They will fill their stomach and their crop with berries right up into their mouth until they can’t fit another berry inside of them.”

 

It isn’t just Nandina berries. Consider the following other incidents with cedar waxwings: South Dakota: killed by eating Cotoneaster flowers; in Nebraska, killed by eating crabapples and cotoneasters; in Indiana: ethanol poisoning from overwintered hawthorn fruit; Texas, killed by gorging on blueberries along a highway.

“They’re cedar waxwings,” said Capt. Garry Collins of Texas Parks & Wildlife, rather nonchalantly. “It’s a natural phenomenon. “It’s seasonal. Happens nearly every year.”

The bottom line: Where there are dense stands of Nandina, late-season berries in some areas might be the sole food source at that time for cedar waxwings. Their feeding habits can lead to mortality events in those regions. But where Nandina is not invasive and is part of a mix of food sources, cedar waxwing mortality is unlikely. If you’re really worried about it, the berries can be cut off, and fruitless varieties are available. The amount of cyanide in Nandina berries is very low, not a risk to you or your family or pets.

Garden Professor ringleader Linda Chalker-Scott had this to say:

I would imagine this is a very rare problem. In the sole report, the only thing the birds had eaten were Nandina berries. I can’t imagine many landscapes that would have only nandina berries available for frugivorous birds. In any case, it makes a good argument for diversifying one’s landscape plantings.

And one of my gardening gurus from decades ago – Ann Lovejoy – wrote “Don’t be afraid of a good shrub” for a paper in Washington State, concluding that “On the basis of this single — if well-documented — report, Heavenly Bamboo is getting a bad rap.”

Ironically, until that fatal day in 2009, nandinas were widely touted as excellent bird food. Those poor cedar waxwings had nothing at all in their tummies but nandina berries, while millions of birds have enjoyed a mixed diet including some nandina berries over the past two centuries. Too much of a good thing can be fatal. While just swallowing a few whole won’t harm you, actually chewing and eating quantities of seeds or pits from apples, cherries, apricots, pears, peaches or plums can make you sick or even kill you. 

Even more to the point, few nurseries bother with the straight species these days. Floppy and leggy, it has long been superceded by compact, non-fruiting forms. Of these, ‘Gulf Stream’ and ‘Moon Bay’ are particularly reliable, long-lived and handsome year-round. Both mature to 4-5 feet high and wide, with colorful new growth as well as good fall and winter color. 

So, should you rip out all your nandina? Not at all. Even if you happen to have the plain Jane species in your yard, you can make sure that it won’t wander or kill off any critters by simply cutting off the spent flowers before they set seed.

Ann wrote the best pruning advice I’ve ever seen for Nandinas (last paragraph here), and recommended them for spots close to doorways. 

“Gulf Stream” Nandina variety, showing its excellent winter color (and no berries).

Why Nandinas are So Popular

In my back garden, Nandinas provide a narrow band of evergreen screening below the Crossvine, which won’t grow low to the ground.

 

More complaints about Nandinas include its invasiveness in some places, and in many more places, its ubiquity. Well, sorry! Sometimes plants are used by seemingly everyone and seemingly everywhere because in disturbed sites that present problems to humans, they’re often the best solution. In the case of Nandinas, based on my experience growing several over 30 years, it’s because:

  • They’re evergreen.
  • Sun or shade – no problem.
  • They come in a variety of eventual heights from 2 to 6 feet and 3-4 feet wide, without sheering. Great for tight spots.
  • Within a year or so of planting, they’re so drought-tolerant you can generally forget about them.

So the next time I open my garden to visitors, I’ll have a link – to this very blog post – to send to accusatory visitors, of which I’m sure there will be more. These are the times we’re gardening in.

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