· by scottzona.bsky.social ·7h ago · view on bsky.app ↗

Buddleja davidii is often called “invasive.” It certainly colonizes disturbed areas (like RR lines), but I’ve never seen it invade intact ecosystems. Weedy on ecosystem edges? Definitely! Invasive? I’m not convinced. 📷: Bluebell Railway nigelmenzies CCBYNCND2 #Scrophulariaceae #Botany 🌾🧪🌱

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Photo of a railway line running through a small, shallow ravine. The slopes of the ravine are covered by pink flowering shrubs (Buddleja davidii). A bridge across the ravine is visible in the background.

#botany #scrophulariaceae

7 comments — live from bluesky

Roland Gromes · 1 · 7h ago

If it prevented the resettlement of ecosystem edges by other plants that would make it invasive, wouldn't it?

🌴 Scott Zona, Ph.D. 🌴 · 4 · 7h ago

The disturbance is preventing the original plants from colonizing, not the presence of Buddleja. If you took away the disturbance that creates the edge, would B. davidii persist? I don’t know.

Brian Eversham · 6 · 7h ago

Interesting discussion. In Britain it rapidly colonises ex chalk/limestone quarry sites and dominates, for decades, where otherwise species-rich calcareous grassland composed of native flora would develop. Many such sites are difficult or impossible to graze, which is probably the missing factor.

Roland Gromes · 1 · 7h ago

Exactly! That would be the important question. And I don't know either. For Fallopia or Impatiens glandulifera I think they are invasive in this way, Buddleja is a maybe afaik

Nick Mitchener 🏳️‍🌈 🔭⚛️ · 0 · 52m ago

It is fantastic for butterflies, bees, hoverflies and moths. We let it grow big each year for them and then cut it right back. The other thing that is brillant is mint

Jackmanii27.bsky.social 🌱 · 1 · 6h ago

That's also the case with other "exotic invasives" like Paulownia tomentosa and Dame's rocket (Hesperis matronalis). Commonly seen inhabiting roadsides and "waste places", not forests and other undisturbed habitats.

Lilesosanna · 1 · 6h ago

have it in the garden - for the insects, it's never invaded anywhere here.

Stephen Heard · 5 · 7h ago

Just had a similar discussion with someone who referred (in passing) to common mullein as "invasive". But I see it primarily on road edges, gravel banks, and open sandy areas where I don't think it's displacing anything native. I argued it's "introduced" and "naturalized" but not "invasive".

dba copedog · 2 · 4h ago

Mullein is my go-to for this argument. Spent a lot of time managing a lot of acreage and have never seen mullein where the soil wasn't already disturbed

🌴 Scott Zona, Ph.D. 🌴 · 3 · 7h ago

“Invasive” gets thrown around too easily.

Stephen Heard · 3 · 7h ago

Yeah, I agree. It's not that "invasive plants" (and animals) aren't a problem - they definitely are. But where I live, something like 30% of the flora is non-native and we need to reserve our opprobrium and our efforts for the ones that really cause damage. (Knotweed, buckthorn, multiflora rose...)

🌴 Scott Zona, Ph.D. 🌴 · 2 · 7h ago

Agree 100%

Dr. Todd Ewing PhD. · 2 · 6h ago

What a beautiful invasion! I bet it smells just a beautiful!

Martin Kroeker · 1 · 6h ago

I guess it depends on whether one considers disturbed areas as ecosystems in their own right ? Certainly most such sites will be man-made rather than natural rockfall nowadays , but if Buddleja outcompetes pioneer shrubs from the local flora it could be considered invasive.

Martin Kroeker · 1 · 6h ago

And apparently Buddleja managed to adapt to European conditions, at least according to some authors www.blackwell-synergy.com/doi/pdf/10.1...