Rosa vosagiaca. Glaucous Dog-rose

Rosa vosagiaca. Glaucous Dog-rose, previously part of Northern Dog-rose pair.

 Rosa caesia subs. caesia (Northern Dog-rose) and its other half Rosa caesia subsp. glauca (Glaucous Dog-rose) , have been split into separate species. Subspecies glauca is now called Rosa vosagiaca.  

This split has made the identification of the most common hybrid rose in Cambridge R, caesia x R. canina =  R. x dumalis more  difficult, as there are now more combinations. 

R. vosagiaca Great Massingham, Norfolk 29th Sept 2026 

 Most Dog-roses in Cambridgeshire are hybrids of either of these two Northern Dog-rose species. 

The previous subspecies of R. canina  (Dog-rose) was split into three separate species R. canina, R corymbifera and R. squarrosa and it has proved quite difficult to find 'pure' examples of each .  My recent blog on R. canina goes through some of the problems, when trying to find a plant that can be photographed, to represent a good R. canina.  By 'pure' I mean a plant that conforms to nearly all the required features as listed in the new BSBI handbook by Roger Maskew and Gareth Knass. Some introgression has to be allowed for as 100 percent purity would be very rare.  

The two 'Northern Dog-roses' have introduced many features into local Dog-roses, however there are no examples of Northern Dog-roses themselves, south of a line from the Bristol Channel to the Wash.

 I was keen to find and photograph a Northern Dog Rose so I could better understand its features.

This proved very difficult as 'UP North', in Yorkshire, County Durham and Northumberland I tracked down grid references for these species only to find plants that failed to have many of the required features. They were it seemed hybrids with mainly R. canina agg. My conclusion is that both species of Northern Dog-rose are a lot rarer than the BSBI maps indicate. 

It was then great news that Lewis Saunders and Alan Leslie had found several bushes of R. vosagiaca in Norfolk. Samples were sent to the BSBI Rose referee, Gareth Knass who confirmed they were R. vosagiaca. 

Follows are some photos of these plants found on a roadside bank at Great Massingham, West Norfolk.

R. vosagiaca and R. canina .agg 26 Sept 2026. on roadside bank.

First impression was a row of about 6 well established large rose bushes with high arching stems ran along the road bank for about 20m. They showed multiple very large orange hips, except the single R. canina agg which had smaller darker red hips. 

First feature was to check, was the hip pedicel which was clear of glands in nearly all samples but very occasionally one or two stalked glands were present.  This was considered acceptable introgression.  The pedicels were very short. 

R. vosagiaca. Typical group of hips with very short pedicels.

The key features of R. vosagiaca are the very short pedicels, large bracts, a large hairy head of stigmas which cover the disc, and a wide stylar orifice. The above photo shows the short pedicel and the bract, although somewhat damaged, is longer than the pedicel.

R. vosagiaca with a large head of stigma with hairs, covering the disc.

R. vosagiaca spit hip showing the orifice is about 1/3rd the diameter of the disc and the hairy stigma.

The above photo also shows that the disc is flat, which is a feature of R. vosagiaca. 

 

R. vosagiaca, abundance of bright red hips.

Another important feature of R. vosagiaca is that the sepals are persistently erecto-patent at least until the hips are ripe. The above photo shows that the sepals are starting to fall off, because the hip is quite ripe although still firm. Just before falling off they are raised to an upright position.

R. vosagiaca Hips showing raised upright sepals just before falling.

R. vosagiaca, close up of sepals showing some stalked glands and some pinnate side protrusions.

Leaves.

R. vosagiaca. New growth leaf showing folded leaflets and slightly glaucous darker upper surface and paler underside.

 

R. vosagiaca. Leaf shape: leaflets well spaced apart, quite narrow and not very pointed at the apex.

Leaf shape in all dog-roses is known to be very variable according to Tony O'Mahony who has studied roses in Co Cork for many years. The above leaf shape certainly fits with the new handbook but details like margin type, glands and hairs are probably much more important than shape.

Leaf margin.

R. vosagiaca. Leaf margin: mainly uni-serrate with some partial bi-serrate tips. 

 No glands present except a few on the margin towards the base of some leaves and no leaf hairs, glabrous on both surfaces. All good as defined in the new handbook.

R. vosagiaca. Rachis has some stalked glandular hairs.

The handbook suggests most plants have no hairs and are eglandular or occasionally have a few scattered glands and pricklets. Maybe this indicates some introgression with a species that has glands.  

Stipules. Not covered in the new handbook but Tony O'Mahony documented that Dog-roses have elongated glandular tips which fall off quickly, whereas Sweet Briars and Downy Roses have round glandular tips which stay on.  See separate blog covering this feature, which works on over 95% of roses tested in Cambridgeshire. 

R. vosagiaca.

The round glandular tips and fact they are staying on the margin, as shown above, suggests that some introgression with a non Dog-rose has occurred but since the only other variance with the expected set of features, is the sparse stalked glands on the rachis it can be accepted as R. vosagiaca. This was confirmed by Garath Knass who considered there might be a very small introgression with a Downy rose. 

If I find this type of variance, I double check features, for example, do a more thorough check to see if any acicles are present, in order to see if an element of R. rubiginosa might be the culprit.

R. vosagiaca New shoot showing wine-red pigmentation.

R. vosagiaca Prickles on new shoot. 

  

Typical dog-rose prickle.

Conclusion.   

At long last I have taken a reasonable set of photos of one of my target species, R. vosagiaca. I thank Lewis Sanders and Alan Leslie for finding these plants and also arranging for the BSBI referee Gareth Knass to check out a sample. It was impressive that Gareth Knass came back quickly with an excellent critique and confirmed that he considered the sample to be R. vosagiaca.  

A remaining question is whether these roses were planted or arrived naturally, as they are just outside the normal distribution range. There was no indication that they had been planted, except a bit further up the bank beyond a gate there was a single rose bush of a type of garden rose. 

At some stage it would be nice to find a R. caesia but that might be next year now. 

Garden type rose.

Garden type rose just south of site.


Peter Leonard
2nd October 2026

R. vosagiaca vs R. canina .agg (right) split hips. 

 

Rosa tomentosa Harsh Downy-rose

Rosa tomentosa Harsh Downy-rose.

A few post flowering photos taken on 2nd July 2026 in Cambridgeshire.

Rosa tomentosa, outstanding feature is the very long pedicels with lots of glands.

The pedicel glands immediately rule out those tricky Dog-roses, so this is definitely an interesting plant. The length of the pedicels being up to 3cm is quite extreme. We are looking at a Sweet Briar or a Downy rose and long pedicels are really only found in either R. micrantha or R. tomentosa.

These two share many common features but R. micrantha would have 'few to many' obvious glands on the underside of the leaf. amongst some hairs. often limited to veins.

R. tomentosa would normally have high density of hairs on the leaf underside, although this is a variable feature and some plants have a much lower density. Stalked glandular hairs on the underside of the leaf can often be absent here in Cambridgeshire or on occasion quite a lot can be present.  If large glandular tips are present, (0.1mm diameter), consider looking for acicles just in case you have found the rare hybrid with R. rubiginosa.

R. tomentosa Underside of leaf showing quite dense hairs and the odd gland on the surface.

Many R. tomentosa plants in Cambridgeshire have a very high density of hairs, being fully tomentose and no glands visible on the leaf surface. This plant has a few glands on the surface and more on the secondary veins and lots on the main vein. It is the leaf surface glands that are most useful for identification in that they are small downy rose type at about 0.05mm diameter. The sweet briar equivalent glands would be 0.1-0.12mm in diameter.

At higher magnification they have stalks and a tiny glandular head not much thicker than the stalk.

The odour of leaf glands can be smelled, but is not as strong as that of R. rubiginosa or R. micrantha.  

So we have glandular pedicels, long pedicels, dense under leaf hairs and even some glands ( not always present) so next up is to look at the leaf margin.

The new BSBI Rose handbooks suggest the leaf margin of R. tomentosa should be biserrate or multi serrate. As usual, the major tips have hydathodes supplied by a vein, and the sides of the tips have secondary minor sub-tips with stalked glands.

 We do not have the major tip, then secondary smaller tip sequence here ( biserrate), just major tips with minor tips caused by the stalked glands. To me this is multi serrate. Tony O'Mahony in Ireland expects R. tomentosa to have multi serrate margins and biserrate or serrate edges may indicate  a cross to R. corymbifera, at least in County Cork. 

The distinction between hydathodes and glandular tips can occasionally become blurred as I have seen glandular tips which are at the end of a vein and also hydathodes which are not the normal conical shape and have a round ball, however this is unusual. See previous blog on Rose leaf margins.

This is all good for R. tomentosa but R. micrantha also has a similar leaf edge. Both are multi-serrate. Many other features are shared, like a flat to slightly convex disc and a narrow orifice.

R. tomentosa Slightly convex disc with a narrow orifice at 0.8mm max.(1/5th diameter. of disc.)

R. tomentosa Orifice small and you can just see some hairs in the styles although broken off to show the size of the orifice.                                                              

R. tomentosa Close up of orifice with cylindrical hole and some remaining styles and hairs.

According to the new handbook the styles can be glabrous or slightly hairy whereas in R. micrantha the styles should be glabrous (no hairs).   A minor point to suggest the plant is R. tomentosa.   

A wider orifice opens up other species like R. sherardii  and mollis and hybrids. It is always worth cutting a hip through the orifice to check shape and diameter as it is one of the more important features in confirming an identification.

To complete the set of photos, next up is a close up of the leaf stipule. 

R. tomentosa Leaf stipule and petiole ( leaf stalk). 

Not only the margin but also the stipule surface is covered with large stalked red glands. The margin is showing round stalked glands which are staying on, unlike the stipule glands on the Dog roses.

R. tomentosa Sepal, hairy on top surface and glandular beneath with pinnate side projections. often sepals can have leaf like extensions, see bottom left. 

These sepals are slightly reflexed when you might expect the sepals to be spreading-erect, however it is now known that the sepals of R. tomentosa  are very variable in the angle they take up and can be very variable on the same plant. They also can fall off quite quickly.

R. tomentosa 

Final shot of a prickle showing quite a strong straight shape whereas R. micrantha would have a more curved prickle.

Conclusion.

I was happy that this plant fitted the requirements of being a R. tomentosa. The narrow orifice is useful in discounting the other Downy roses ( R. sherardii and R. mollis, see separate blog) and was interested to see how many features were shared with R. micrantha. 

With all roses you have to look at all features before deciding what name to put on it and even then recheck to see if everything fits or suggests a hybrid. The main problem with hybrids is weighting the importance of features to decide what possible parents have been involved. Not easy.

Peter Leonard

Cottenham, Cambridgeshire, UK

July 2026 

Reference. Wild Roses of Great Britain and Ireland by Roger Maskew & Gareth Knass, BSBI Handbook no 26, 2025.

Additional photos.  R. tomentosa usually has hairs on upper surface of leaf which this plant did but the hairs were quite hard to see and was variable in density. R. micrantha usually does not have upper leaf hairs.

2Jul26, upper leaf. R. tomentosa.

A better photos from 2021 showing upper leaf hairs.

20Jul21, R. tomentosa, Royston.

Tolpis staticifolia from Salzburg.

Tolpis staticifolia from Salzburg.

A few holiday photos from a visit to Salzburg,  and a new plant for me. 

First plant of interest was found while visiting the Hohensalzburg Fortress overlooking Salzburg. 

Tolpis staticifolia, 3rd June 2026. 

  A slightly different yellow composite as it showed a dark centre to the flower. 

The dark centre attracted my attention, as this was something different.

Very narrow leaves, all basal and leafless stems helped identification.

Narrow leaves lacking hairs also with a paler main vein.

Close up view of the inner florets show a different terminal structure to the outer florets, which is why the centre is darker, although photos on the web show this is not always a prominent feature. 

Although I did not notice this at the time, the photo shows the ray florets (ligules) are hairy on the undersides, an unusual feature. The narrow phyllaries (involucral bracts) have cobwebby white hairs only.

Final shot showing flowering stems are simple or sparingly branched. 

Identification was based using the book, The Alpine Flowers of Britain and Europe by Christopher Grey-Wilson and Majorie Blaney, 1979.  On return from my holiday, I purchased Europe's Alpine Flowers by Bob Gibbons part of the WILDGuides series. This recent book covers more species and contains concise useful information. 

Tolpis staticifolia  was previously called Hieracium staticifolia and it is hard to find more detail on its characteristics.  The hairs on the underside of the ligules and the strange terminations to the inner ligules, which make the centre dark, are unusual, but I didn't find any reference to them in a limited search of either the web or standard literature.  

Peter Leonard

Cottenham, Cambridgeshire, UK

7th July 2026

 

Rosa canina (Dog-rose) identification.

Rosa canina (Dog-rose) identification.

With R.canina agg. being split into  three species, R. canina, R. corymbifera and R. squarrosa I thought I would take a few photos of a 'perfect'  R. canina (or R. canina stricto sensu) in Cambridgeshire.  

The main problem is finding an example of R. canina s.s. which conforms to the new handbook description and does not show features of the two northern dog-roses or R. corymbifera and R. squarrosa.

I don't want an example which has:-

Glaucous coloured underside to leaves or folded leaves.

Zig zag stems.

Stems that show a red colour.

Short pedicels suggesting hybrid with Northern Dog-rose.

Short pedicels with large bracts that obscure the pedicels. R. canina s.s. should have pedicel length in the range 1-2.5cm whereas northern dog-roses should be in range 0.5-1cm and the hybrids could be anywhere, but I would like an example with some pedicels at least 1cm. 

Large hips especially if round/spherical.

R. canina s.s. should have a 'temple dome' shaped uni-serrate margin to the leaves without any glands, so NO glands.

Soft hairs or glands on the petiole/rachis. 

Odd looking prickles.

Leaf stipule glands that stay on and are round rather than slightly elongated.

That's probably enough features I don't want, but there are probably more. This proved quite hard as most R. canina potential plants failed, for one reason or another. 

Pedicel has no glands. A key feature of the Dog-roses.

My selected potential R. canina growing in Wicken Fen.

Erect and arching stems.

Pedicel has no glands and is over 1cm, not enclosed by bract.

Sepal is pinnate and should not have too many secondary side projections or too many glands to be acceptable for R. canina.   Sepals of the three dog-roses R. canina, R squarrosa and R. corymbifera become reflexed as the hip ripens and fall off early.   Sepals of R. squarrosa might have more glands on the tips of the pinnate side projections.

Orifice is narrow and the disc is conical. A conical disc is very common in Cambridgeshire for R. canina.  Sometimes this conical disc is given the name R. canina var. spuria according to the new handbook. The orifice is deep and has vertical groves from forming around the style. 

Next photo shows the sepals have already become reflexed even though flowering has only just finished and the hips have not started to turn red. The rate that sepals move seems very variable even on a single plant but the fact that on this plant they have reflexed early is a good sign for R. canina.

Next the leaves. Green on top and flat not folded.

The leaf has several important features to consider. 

Uniserrate margin with hydathodes only, no glands.

Underside just a paler green. Margin is uniserrate, no glands.

Petiole and rachis has no glands or hairs on. A key feature.


Leaf stipule.

The leaf stipule glands are falling off and the remaining ones are elongated in shape which conforms to Tony O'Mahony's discovery that roses in the subsection caninae ( Dog-roses) have these features. See previous blog that covers this subject. I always pick a new leaf from a new shoot for this test if possible.

Prickles.

It often surprises me the variation in prickles on a single bush but the above conform to what I would expect for a R. canina, in that they have a broad base and are variably hooked. I have seen quite a few potential plants of R. canina locally, near Swavesey, that have very straight prickles which don't look right and suggest some introgression, but what with, is a puzzle.

Conclusion.

The above photos I think are a good example of what a Rosa canina should look like at the post flowering stage. The well known problem that every Dog-rose bush looks slightly different, so you have to accept quite a lot of variation but where to draw the line and decide it no longer fits the 'perfect' R. canina is a challenge.  Some introgression is allowed, otherwise very few roses would be identified beyond R. canina Agg.

Finding a good example of R. canina was quite difficult as most plants have features that could indicate more than a little introgression with another, now separated species, either R. corymbifera, R. squarrosa or more frequently R. vosagiaca / R. caesia. Hybrids with species outside the Sub-group caninae also occur and another rose bush at Wicken Fen seemed to some features of R. rubiginosa with large glands on the underside of the leaves and just the odd acicle.

The above is a personal view but based on the new BSBI Rose handbook which was published in late 2025.

Peter Leonard

Cottenham, Cambridgeshire.

July 2026

An example of a plant that didn't make the grade.

There above photo of a rose near Longstanton, shows a potential R. canina but the sepals are not reflexing at all and are starting to fall off. This suggests some introgression with either R. caesia or R. vosagiaca ( Northern Dog Roses) and the leaves were also folded more than I would have liked. All other features of this bush aligned with R. canina and the observation than no hairs were present on the leaf might suggest this plant has a tiny amount of R. vosagiaca in it. R. canina x R. vosagiaca = R. xsubcanina.