Nettle Family [Urticaceae] |
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23rd March 2016, dog hole cave, Cresswell Crags, Derbyshire. | Photo: © RWD |
Half inside a limestone cave, it spreads by long runners. |
23rd March 2016, dog hole cave, Cresswell Crags, Derbyshire. | Photo: © RWD |
Leaf-clusters before flowering. Leaves have a large variety of sizes. |
17th Aug 2007, Whatstandwell, Cromford & High Peak Railway. | Photo: © RWD |
It takes root in cracks in walls, this one with cement pointing. |
17th Aug 2007, Whatstandwell, Cromford & High Peak Railway. | Photo: © RWD |
Spreading across the surface about a foot across, and perhaps up to 8 inches high. |
31st Aug 2018, broken brick beach, Hightown, Sefton Coast. | Photo: © RWD |
Your Author was surprised to find the plant growing flat on the shoreline where the bricks from bombed Liverpool were dumped and have now been washed onto the shore. This area is washed by high tides (but no green grass), which either means that Pellitory of the Wall is salt tolerant to a high degree, or it hasn't yet experienced a high tide (which would probably wash it away). But if so, it must still be salt tolerant to some degree; for the area must have some concentration of salt here which has not been washed away by the rain (but then, there has been precious little of that this Summer - only now in the early Autumn have we had a little rain). |
17th Aug 2007, Whatstandwell, Cromford & High Peak Railway. | Photo: © RWD |
The leaves are lanceolate, shiny, with prominent veins. |
17th Aug 2007, Whatstandwell, Cromford & High Peak Railway. | Photo: © RWD |
Clusters of tiny red flowers flowers grow in the leaf axils. Those near the end of the stalk are female only with their tiny fuzzy purple-red stigmas just protruding. Those further down are hermaphroditic (=bisexual) flowers, with both male and female parts in one flower. |
17th Aug 2007, Whatstandwell, Cromford & High Peak Railway. | Photo: © RWD |
The leaves are alternate along the stem.
Female flowers are at the tops of branches, you may just discern the style with a pink 'brush-like' tip protruding from two flowers near the tip of the branch. |
16th June 2010, a wall, Colwyn Bay, N. Wales | Photo: © RWD |
Supporting the 'female flowers grow near the tip of a stalk' hypothesis of one source, these are the brush-like stigmas of female flowers. Note vein-pattern of leaves |
16th June 2010, a wall, Colwyn Bay, N. Wales | Photo: © RWD |
The furry stigmas of female flowers. |
11th Aug 2015, a wall, Burscough Bridge, Lancs. | Photo: © RWD |
Leaves hairy, alternate and without teeth (entire). There are two sets of tiny flowers, those at the summit which are female, and those in small bunches (from 3 to n) at the leaf-axils which are bisexual (hermaphroditic). |
2nd Aug 2013, Hilbre Island, Wirral, Merseyside. | Photo: © RWD |
Hairy red petals. Leaves have long hairs which emerge from tiny bumps like those of Bugloss. Stem angular in places. |
17th Aug 2007, Whatstandwell, Cromford & High Peak Railway. | Photo: © RWD |
The sepals of bisexual flowers become tubular in fruit, so these must be the bisexual flowers in fruit. Every part is covered in short white hairs. |
10th Sept 2015, a wall, Hilbre Island, The Wirral. | Photo: © RWD |
Here all the sepal tubes have elongated meaning that these are bisexual flowers which are in fruit, having been pollinated. |
2nd Aug 2013, a wall, Hilbre Island, The Wirral. | Photo: © RWD |
There are two types of flowers on Pellitory-of-the-Wall plants: female and bisexual (hermaphrodite), because these have doubled creamy-white anthers these must be bisexual flowers. Male parts consist of 4 cream-coloured splayed-out stamens with doubled anthers at the tips.. |
10th Sept 2015, a wall, Hilbre Island, The Wirral. | Photo: © RWD |
Here the anthers have opened up to look like white petals and are now devoid of pollen. One of them is missing, presumed flung sling-shot as the stamens spring suddenly outwards from the confines of the four red tepals (now behind and shorter than the stamens). The pale green fruit is just about discernible deep in the centre. |
10th Sept 2015, a wall, Hilbre Island, The Wirral. | Photo: © RWD |
One of the double-anthers, devoid of pollen. The anther itself is 'fibulated' (ribbed like a rack in a rack and pinion cog - The grooved flower stalk on Dwarf Mallow is also ribbled like a 'rack' [but no pinion]). The pale-green fruit here may be sterile? |
11th Aug 2015, a wall, Burscough Bridge, Lancs. | Photo: © RWD |
Bisexual flowers in leaf axil: Four red sepals behind 4 ribbed flattened re-curved stamens (the anthers have dropped off - possibly flung off as the anthers spring back suddenly). In the centre of the between the anthers is a conical pale-green fruit growing. |
31st Aug 2018, broken brick beach, Hightown, Sefton Coast. | Photo: © RWD |
The 4 wide and ribbed filaments protrude from the sepals and are bent over backwards with their anthers open as thin white double-cups. |
31st Aug 2018, broken brick beach, Hightown, Sefton Coast. | Photo: © RWD |
Another viewpoint of the same open bisexual flower; this time the style is visible deep in the centre. |
11th Aug 2015, a wall, Burscough Bridge, Lancs. | Photo: © RWD |
The stamens are highly elastic and spring back when the flower opens, throwing the pollen out, of which there is reportedly a lot. The pollen is also highly allergenic to some folk. |
10th Sept 2015, a wall, Hilbre Island, The Wirral. | Photo: © RWD |
A fertilised fruit will develop beneath this central red style, stigma now spent and brown. Not the bracts are covered in transparent and hooked 'white' hairs for some reason, presumably to cling to animals clothing and carry off a ripened fruit within to grown elsewhere. |
10th Sept 2015, a wall, Hilbre Island, The Wirral. | Photo: © RWD |
One of the bisexual flowers, with both male and female parts? |
Some similarities to : Related to: Mind-Your-Own-Business (Soleirolia soleirollii) and to Stinging Nettle (Urtica dioica). Minute female flowers grow at the tips of the stems, whereas the male flowers grow in clusters within the leaf axils (as one book says) whilst another book (Stace) says that both female and bisexual (hermaphrodite) flowers grow on one plant. But yet another book claims that the flowers are female towards the centre surrounded by either bisexual or male flowers (Readers Digest). You pays your money and takes your choice...
The pollen of Pellitory-of-the-Wall contains a dodecapeptide which accommodates the strangely-named dominant epitopes The hairs of the flowers are sticky but do not, like those of the related Stinging Nettle, sting.
There also exists a very much rarer but introduced and naturalised alien: It grows on old town walls, at the foot of walls, rocks, rubble, or on churches and castles almost throughout the UK. Also on hedge-banks and is a deciduous herbaceous perennial. It is equipped with tiny hooked hairs which hook on to animals fur to be transported elsewhere. It spreads by blown or carried seed. No types of the three differing flower forms possess petals; but the red calyx can take three different forms: flat, bell-shaped, or tubular hairy and erect.
The sexual composition of the flowers is very complicated, with three types of flowers on the plant and are mostly Another source claims that the Fertile flowers are are one of four types: Hermaphrodite and functionally male and female; Hermaphrodite but functionally male; or Hermaphrodite but functionally male. Unisexual flowers are also present, either male, or female. Which together make for five types of flower. In some sexual forms, the stamens only develop after the stigma has protruded from the calyx. Only after the style has dropped off do the anthers un-furl from their confines explosively, scattering their extensive quantities of pollen about, too late to pollinate its own style. The flowers are anemophilous: scattering their pollen on the wind. The male flowers are like those of Stinging Nettle to which it is related. The female flowers have a 4-lobed and brush-like stigma. The fruits are small and when ripe either fall to the ground or are whisked away by the wind.
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Parietaria | judaica | ⇐ Global Aspect ⇒ | Urticaceae |
Parietaria (Pellitories-of-the-Wall) |
Nettle Family [Urticaceae] |