Bursaria spinosa subsp. spinosa

Blackthorn, Boxthorn at Mount Majura

Request use of media

Identification history

Bursaria spinosa subsp. spinosa	20 Apr 2024	abread111
Bursaria spinosa	1 Mar 2024	Tapirlord
Bursaria spinosa subsp. lasiophylla	1 Mar 2024	Tapirlord
Bursaria spinosa subsp. lasiophylla	1 Mar 2024	abread111

Identify this sighting

Please Login or Register to identify this sighting.

User's notes

6 of these in pink guards

12 comments

abread111 wrote:

1 Mar 2024

@Tapirlord I think I made a mistake, I cannot see the hairs on the back of the leaves, can you?
So maybe it is subsp spinosa
Barbara

Tapirlord wrote:

1 Mar 2024

There isn't really enough detail in the images to be sure, I had assumed these were natural plants hence subsp lasiophylla; since this isn't the case let's leave it without the subsp ID

abread111 wrote:

1 Mar 2024

I'll check again next time I am there.

Mike wrote:

1 Mar 2024

PlantNet says lower surface of leaves ‘densely covered in dense hairs’ and to me this looks like grey underside unless you magnify it. So says a non-botanist. 🙂

waltraud wrote:

2 Mar 2024

We (FoMM) don't know who has planted them and from where the seedlings were sourced. The species might well be the non-local Bursaria. According to the ACT Census of Vascular Plants there is one naturally occurring local Bursaria which is B. spinosa subsp. lasiophylla, Australian Blackthorn. See also discussion around Bursaria spinosa that FoMM planted by mistake - in this case the source was Greening Australia and they gave us Bursaria spinosa subsp. lasiophylla replacements.

waltraud wrote:

13 Mar 2024

the grey underside visible in the second photo indicates the dense hair cover Mike refers to so I think / hope it is the local subsp.
I haven't found out yet who planted.

abread111 wrote:

20 Apr 2024

Sorry, I did check again and it is NOT the local subsp. No hairs on underside of leaves. Adding extra photo to show this.

waltraud wrote:

23 Apr 2024

But the second photo seems to show the underside with hairs i.e. beige colour which would indicate lasiophylla. need to collect sample and I hope that ranger Riley who planted the Bursaria can confirm the species when he is back in Canberra.

abread111 wrote:

23 Apr 2024

Wal, there are no hairs, I did collect a sample and looked under magnification. B.

Mike wrote:

24 Apr 2024

Flora of Australia says 'Very similar to Bursaria spinosa subsp. spinosa, but subsp. lasiophylla retains a more erect multi-stemmed shrubby form and most parts of these plants are heavily tomentose with persisting appressed white hairs, particularly the undersurfaces of the leaves. Bursaria spinosa subsp. spinosa is rapidly glabrescent. Both subspecies have tiny sepals and bracts ( < 2 mm long) that are rapidly shed as a unit at petal break, and the stands generally display a range of developmental stages from very juvenile to adult forms.' and 'The two subspecies are fairly easy to distinguish as the autonym, Bursaria spinosa subsp. spinosa is replaced by Bursaria subsp. lasiophylla on heavier clay soils at higher altitudes in tablelands and lower mountain ranges in south eastern Australia. Subsp, lasiophylla may represent a clinal form of the common glabrous subspecies.' For subsp. spinosa it says 'This subspecies is fairly easily distinguished as the rapidly glabrescent leaves are slightly longer and narrower and the petals are longer than those in subsp. lasiophylla.' Other sources distinguish by the size and shape of the leaves.

abread111 wrote:

24 Apr 2024

thanks, Mike, the problem is these are small, planted relatively recently and some nurseries just sell B. spinosa without bothering about subsp. So no matter what ranger Riley says he planted, we need to be sure of the ID by looking. Previously The Fair planted what was supplied as B. spinosa subsp lasiophylla and found that some of them were B. spinosa subsp spinosa.

waltraud wrote:

24 Apr 2024

okay Barb the apparent beige colour seems just to be just a light effect. Question is what to do. It is not desirable to grow non-locals which may or may not spread and hybridize with the locals. At our Fair project site we remove those that we can identify as B. spinosa subspecies spinosa that Greening Australia gave us by mistake. We may need to consult with an expert because these are PCS plantings; someone other than a volunteer need to convince PCS that planting of non-locals isn't a good idea...

Please Login or Register to comment.