MOUSE-EAR HAWKWEED

MOUSE-EAR-HAWKWEED

Pilosella officinarum

Daisy & Dandelion Family [Asteraceae]

month8may month8jun month8june month8jul month8july month8aug month8sep month8sept month8oct

status
statusZnative
flower
flower8yellow
inner
inner8red
morph
morph8actino
petals
petalsZMany
stem
stem8round
sex
sexZbisexual

10th June 2009, ex-rly track, Smardale, Yorks Dales. Photo: © RWD
Mouse-ear-hawkweed is not a Hawkweed (species of Hieracium) but rather a Pilosella species of which there are only a few in the UK. It grows on rocks and stones (as here on a gravelly ex-railway) or short grasslands on well-drained soils. A single leafless stalk bears a single yellow flower.


10th June 2009, ex-rly track, Smardale, Yorks Dales. Photo: © RWD
The flower stalks are un-branched, leafles and up to 30cm tall (max 50cm). Leaves have a silvery edge, with long hairs on the upper mid-green surface but whitish with hairs on the underside. They are oblanceolate (wider nearer the far end and narrowing towards the flower stalk and are stalkless). There are more basal rosettes than there are flower stalks, they spread by rooting another smaller basal rosette nearby.


29th May 2010, ex-quarry, Hodbarrow, Millom, Cumbria Photo: © RWD
The flowers have a fairly wide cup and dandelion-type flowers which are a paler yellow than Dandelions. Often the outer parts of the outer ray florets are tinged a pale red, but not always.


22nd June 2007, Castlefields Basin, Bridgewater Canal, M/cr. Photo: © RWD
Specimens A. Black and long stem hairs and shorter hairs on sepals, neither glandular on this specimen. Long white hairs on leaves. The upper stems of these specimens are covered in ants. Here only the tips of the outer ray florets are tinged pale-red.


22nd June 2007, Castlefields Basin, Bridgewater Canal, M/cr. Photo: © RWD
Specimens A. Black and long stem hairs and shorter hairs on sepals, neither are glandular on this specimen.


22nd June 2007, Castlefields Basin, Bridgewater Canal, M/cr. Photo: © RWD
Specimens A. The basal leaves. No Mouse-ear Hawkweed has leaves on the stems. The lower stems may have long thin white hairs (rather than perhaps black above), as do the leaves. The long white hairs on the leaves may come from a tiny blackish pimple.


8th June 2005, Ashford-in-the-Water, White Peaks, Derbys. Photo: © RWD
A birds-eye view of the lemon-yellow flowers.


8th June 2005, Ashford-in-the-Water, White Peaks, Derbys. Photo: © RWD
The un-opened flowers are much redder - three are visible here. It looks like these specimens are extending trial runners with leaves attached to perhaps become basal rosettes a bit further (if there was any Earth there for them to take root!).


10th June 2009, ex-rly track, Smardale, Yorks Dales. Photo: © RWD
The end of the ray florets is square with 4 cuts (making 5 florets per ray floret). The florets in the centre have 2 concolorous yellow stigmas atop a style.


3rd June 2017, Wolfscote Dale, White Peaks, Derbys. Photo: © RWD
An un-opened flower bud - they look a little like unopened flowers of Orange Hawkweed (Polosella aurantiaca) at this stage, having deep-red outer florets. The shorter disc florets are all huddled inside. There are two rings of narrow sepal teeth cupping the flower, a shorter outer set and a longer inner set. The exact appearance of the hairs on the sepal teeth is variable. There are usually black, but whether they have tiny spherical glands at the ends or not is variable. So too is whether they have conical bases or not. This specimen has both spherical glands at the tip and conical bases. The hairs sometimes split into two or three near the ends (stellate hairs).


23rd May 2008, Shell Island, Llanbedr, Welsh Coast. Photo: © RWD
This specimen has both spherical glands at the tip and conical bases. The hairs sometimes split into two or three near the ends (stellate hairs) [just left of dead-centre].


29th May 2010, ex-quarry, Hodbarrow, Millom, Cumbria Photo: © RWD
Black hairs on the sepal teeth: This specimen lacks the globular glands at the ends, but does have conical bases. The hairs have longer white extensions further down, with some being very long indeed.


5th June 2006, Potters Tarn, Staveley, Cumbria. Photo: © RWD
Flowers just a short time before opening fully.


10th June 2009, ex-rly track, Smardale, Yorks Dales. Photo: © RWD
Leaves with long white hairs.


29th May 2010, ex-quarry, Hodbarrow, Millom, Cumbria Photo: © RWD
A typical basal leaf with either 3 or 6 leaves. The leaves are stalkless and winged where they taper to the flower stem.


10th June 2009, ex-rly track, Smardale, Yorks Dales. Photo: © RWD
Leaves white beneath with short matted hairs and shaped like the ears of mice, hence the name of the plant.


Not to be semantically confused with : Mouse-ears such as Common Mouse-ear (Cerastium fontanum) nor with Mousetail (Myosurus minimus) nor Mousetail Plant (Arisarum proboscideum). Nor with species of Hieracium such as Spotted Hawkweed (Hieracium maculatum) [plants with similar common names]

Mouse-ear Hawkweed exists as seven species / hybrids which Clive Stace thinks should be better described as being just varieties rather than hybrids or sub-species. These differ in several features making the features in the above photos differ from each other, in the way the hairs are black or white, simple or glandular, with splits in the ends (stellate hairs) or not and variations in their length. Also in the reddish colouring of some petals, or not and whether the stolons are stout or slender and long or short, the flower stems leafy or not and the size of the flower. Thus varieties called Spreading Mouse-ear-hawkweed, Tall Mouse-ear-hawkweed and the [RRR] rare Shetland Mouse-ear-hawkweed are encompassed in these 7 variations. Some of these variations also occur more often in certain places in the UK, but apart from the rare Shetland variation can also be mixed in with other populations.

The above photographs, because their characteristics vary between themselves, will be several of these 7 varieties (except for the rare Shetland one which is found only in Shetland).

Uniquely identifiable characteristics

Distinguishing Feature : The long hairs on the basal leaves which are shaped like the ears of mice.


  Pilosella officinarum  ⇐ Global Aspect ⇒ Asteraceae  

Distribution
 family8Daisy & Dandelion family8Asteraceae

 BSBI maps
genus8Pilosella
Pilosella
(Mouse-Ear Hawkweeds)

MOUSE-EAR HAWKWEED

MOUSE-EAR-HAWKWEED

Pilosella officinarum

Daisy & Dandelion Family [Asteraceae]