Polypodies

A magnificent fern grows on an old Ash-tree on the banks of the Dordogne. It is a Polypody, but which one? There are three species in Perigord and sometimes a hybrid between two of them is found. The species are very much alike. To be sure of your identification you have to look at the sores (the lids of the sporangia) under a microscope et count the cells. Well, in the field you normally don't carry a microscope.

Hybrids are often polyploids - the number of chromosomes has doubled or tripled - and thus the organs (leaves, flowers) can be much larger than those of the parents. This one is really big, it has fronds up to 70 cm. So probably it is the Hybrid Polypody (Polypodium x mantoniae).

It has other characteristics of its presumed parents. The big pinnate leaves are long triangles with toothed margins as in the Intermediate Polypody (Polypodium interjectum). The leaves are planar, the pinnae - the segments of the leaves - are a bit hanging in the picture but they are basically all in two dimensions as in the Common Polypody (Polypodium vulgare).


In this fallen tree lives one of the two parents, Common Polypody, as in an apartment building with several floors.

They are rather small and the fronds are long with parallel margins.

Often Polypodies grow on trees, but you can find them also on the forest floor. Or maybe this one lives on a dead trunk hidden under fallen leaves? Possibly this is an Intermediate Polypody (Polypodium interjectum) considering the shape of the leaves, slightly triangular with the basal pinnae uplifted. But this is just a guess!

Burr Cucumber

Burr Cucumber (Sicyos angulata) is an invasive plant that loves summer sun and humidity, two things abundantly available on the Dordogne river banks. This plant from North America can be found in the West of Aquitaine since about fifty years and, following the rivers, it makes progress in the East. Slowly, in 2010 it had not yet arrived in Bergerac. But now there are also Burr Cucumbers in Coux et Bigaroque and maybe also further away.

It is a kind of monster, its creepers can reach more than 8 meters away. It covers the river banks and their vegetation, and it climbs...

... and climbs. In fact, it thrives like a cucumber or a pumpkin on the compost heap. As it should be for a member of the Cucurbitaceae family.

Until now there has not been a little morning frost this year, so Burr Cucumber goes on flowering.

It is not easy to find beauty in it, it is a messy plant, with its unkempt creepers and disheveled leaves that grow in any direction. But this is also a question of taste, is n't it?

The star-like fruits are festive, anyhow, like too-early christmas tree baubles.

In spite of its name the fruits do not look at all like cucumbers, nor are they edible. By contrast the leaves resemble much the leaves of a kitchen cucumber plant.

Common Michaelmas Daisy

Like dirty snow too early in the year. The banks of the Dordogne are covered in a mass of tiny white flowers. Common Michaelmas Daisy (Symphyotrichum x salignum) is an American and it looks like it is happy to be in France.

It colonizes the banks of rivers. It takes only a few years to cover a whole surface with dense and chaotic vegetation, by means of its rhizomes that go everywhere. An invasive species is supposed to make life difficult for indigenous species, thus Common Michaelmas Daisy is considered to be an invasive. Since 200 years it lives in France, but only recently it spreads really fast. Why? Maybe because the long and warm autumns of the last few years helped it grow and flower during a long time? Should you call it a pest? That would be exaggerated, or?

Large stalks stand up or lay down, here they are draped over a dead branch. They carry loose clusters of composite flowers.

 Ligulate flowers are whitish with often a tinge of pale lilac, and the tubular flowers, nearly invisible in the image, are yellow. The stem is more or less hairy.

In the background you see the trunks of some Ash-leaved Maples (Acer negundo), a very common tree in the river woodlands of the Dordogne. This one is also an invasive species of northamerican origins.

Field Maple

Leaves are turning into gold.

Hera a leaf of a Field Maple (Acer campestre). This tree is easy to find in the wild but it is also often planted. A row of Field Maple make a good hedge and protect against windy weather and it is easy to trim. It is not a difficult tree, it grows on nearly all kinds of soils (maybe with a slight preference for limestone) and supports very well dry summers.

Here it is embellished with spider webs and lichens.

The fruits are called samaras and they are typical for maples. They grow in pairs, every samara carries a wing, and when they fall down together they turn and wheel like little helicopters.

Some branches with summer leaves.

Floating Primrose-willow

It is supposed to be a really intrusive invasive plant, but, no matter, Floating Primrose-willow (Ludwigia peploides subsp. montevidensis) is pretty to look at.

At the end of summer, yes, until in October, it shows off ist yellow flowers. It grows in water or at in places where land and water touch. Here and there it form dense mats of vegetation on the banks of the Dordogne river or even in the water where there is not much current.

Rosettes of leaves detach themselves from the mother plant and float down the river to new spots.

Autumn Squill

On this roadside colours have changed. It is no longer sallow grey and dry yellow.
Many tiny blue stalks appear from the morning fog.

 

Those are Autumn Squills (Scilla autumnalis) and, never seen before, this year there are so many of them they nearly cover the soil. And they are big, most plants have a dozen of flowers or more. Well, big...

You would not think plants like those dry summers. But maybe, in this case, the underground bulbs took some strenght from abundant and long-lasting spring showers? In summer Autumn Squill has no leaves or stems above ground, so possibly it did not suffer thet much from hot sunshine and drought.

A little white plant between hundreds of blue flowers. Why not?
  

The flowers are still closed, waiting for the sun coming through. In an hour they wil open up like little stars, and it will be more easy to see they are real squills.

There are not only Autumn Squils here. Carline Thistle (Carlina vulgaris) and a tiny Rough Marsh Mallow (Althaea hirsuta) are dried out completely and veiled by spider webs. They also are part of the flora of calcareous meadows.

Hop Trefoil

Like everywhere in Dordogne clovers abound. There are about twenty different species, white, pink or yellow. Hop Trefoil (Trifolium campestre) is very common and like all clovers it leaves consist of three leaflets stipulated at its base. It flowers in May and June, and if the summer is not too harsh and dry it will linger on.

Not this summer. It was rather hot and there was virtually no rain in three months. No problem, most plants in this kind of meadow do survive very well and have a full life cycle, flower, and produce  seeds, before the beginning of the dry season. 

See here the result. A meadow in tints of brown and grey from dried and sun-scorched plants. Yes, there is beauty in it, let's admit it...
The scorching changed the colour of the heads of Hop Trefoil, but not their shape. The Hop Trefoil flower heads are round and brown. The fruits are ripe now, but completely hidden in the dead flowers, like with other clovers the petals stay on the plant after flowering.

Some months ago. The banner - the largest petal of the butterfly-shaped flower - is folded backwards and downwards

Harebell

Little blue flowers grow between the taller grasses on a roadside. Harebell (Campanula rotundifolia) begins to flower at the end of summer and goes on until the first frost. It grows nearly everywhere and the hot and dry August weather does not bother it at all.

Its thin stems carry little blue bells, opening like a five-pointed star.

The english name is easy to understand, they are just the right size for a hare who wants to take home a bunch of flowers to put in a vase. But why the scientific name 'rotundifolia'? There are not many leaves and those you can find are long and slender, not round at all.

You have to go back some weeks. At ground level you find a small plant with round, or nearly round, leaves, young leaves, and all kind of shapes in between. When the Harebell begins to make new sprouts, it starts with roundish leaves. When the season goes on, it makes leaves of a more oval shape. And the newest leaves are outright longish. When at last the first flowers develop, the round leaves have all but disappeared.

'Mountain Needle Sunrose'

The weather is really hot, the sun burns and scorches, plants turn yellow and brown.

Here a 'Mountain Needle Sunrose' (Fumana ericifolia, no English name known) begins to take autumn colours. This very small bush grows at ground level in sunny meadows and other open areas on limestone soil. In spite of the mountain in its name it prefers lowland or hills.

Now there are many rust-coloured fruits, with here and there still a flower.

To see the flowers you should start early, the flowering of this tiny Rochrose is ephemeral and after only a few hours the petals fall.

There exist other Needle Sunroses, but with this one the flowers have long pedicles that bow down after flowering.

Lamarck's Bedstraw

Lamarck's Bedstraw (Galium divaricatum) is too subtle to be seen easily. You look through a cloud of thin stems and very tiny fruits and what you see is essentially the grass that grows behind it. With a camera it is a bit more easy, you focus on the plant and the vegetation around disappears in an out-of-focus blurry.

It is a real Bedstraw, chaotic stems growing in every direction without any regard for the laws of gravitation. You don't know where the plant begins or where it ends.

The square stems have some verticillated leaves at the nodes. Very tiny course hairs give it a rough and scabrous feel when touched.

Concerning the flowers, they exist but you need a magnifying glass to see them, a flower measures half a millimeter maximum. A small reddish or pink bump on the young fruits, that's all. In theory they are star-shaped with four points, like other bedstaws, but this is theory as long as you can't see.

After flowering, the flowers at least respect gravity's laws, the small fruits hang down on short peducules, and this distinguishes Lamarck's Bedstaw from a near relation among bedstraws. Rather subtle, also...

Spotted Rockrose

Some cyclopic objects look at us.

They are petals fallen from a Spotted Rockrose (Tuberaria guttata).

It is a transient flowering. You can look for Spotted Rockrose and not find it, and yet a week later it is there in multitude.

Its favorite habitat is sandy and subnny and not on limestone soil. Here, in a poor meadow after haymaking it grows abundantly.

Many-seeded Slender Tare

This is a very tiny vetch, after flowering it is nearly invisible, unless you really look for it in a calcareous meadow. Many-seeded Slender Tare (Ervum gracile) has a rather long name for such a small plant. 

With some difficuly you can see it is infested by aphids. There were three or two flowers on every flower stalk but only one developed into a seed pod. In this species often the flowerstalk ends in a little point above the flowers or pods.


Two weeks ago it was still in full bloom, with slender curved tendrils.

Now the pods develop. They are a bit transparent and you can see there is a row of several seeds, yes, it is many-seeded for such a small vetch.

 

Dewdrups glisten in the morning sun on leaves, tendrils and seedpods.

 

 

 

Yellow Vetch

In a flowering meadow grows this Yellow Vetch (Vicia lutea) in large amounts. In fact it is not yellow at all, its flowers are white. It has tendrils to climb sunwards in grasses and other plants.

You can see there are many insect visitors. Like many other vetches it has black spots on its stipules. Those spots contain a sugary substance attractive to insects, especially ants.

Also Red Soldier Beetles (Rhagonycha fulva) are fond of Yellow Vetch. Many of them gather on it to meet a partner to mate.

Talking about nuptials, between the flower also hides a male Nursery Web Spider (Pisaura mirabilis) and he carries a parcel between its legs, his wedding present.

He is looking for a female to bring her a prey wrapped in silk. If he comes without a gift, she will eat him immediately without giving him time to make love to her. The present will keep her occupied while he couples with her, and with some luck he will get away with it !

Two vetches

The first thing you see of Coronille minima is its colour. This is what you call yellow! This vetch is a mediterranean species and it has no English name.

It is a perennal plant that grows in dense clumps covered with yellow flower crowns. This year they are bigger as usual, it has rained so much that even in the arid places it prefers it grew bigger and bigger.

You nearly cannot see the leaves, there are so many flower heads! Every leaf consists of about a dozen small folioles, and they are thick, as if they are cut from a sheet of handicraft foam.

Apparently the same type of foam has been used to cut the leaves of another Coronilla, the Scorpion Vetch (Coronilla scorpioides) here below. They are the same greyish-green, but bigger and more irregular.

Its flowers are small and its fruits are long. In fact they look very much like a scorpions tail.

Here it grows in a cultivated field, but you can meet it also in a dry calcareous meadow.

Dwarf Spurge

Dwarf Spurge (Euphorbia exigua) is the smallest Spurge in Dordogne. Some full-grown plants are not bigger than two centimeters. It grows in calcareous meadows, especially in spots where vegetation is sparse and the soil is visible.

The species is rather diverse. Often the plants are greyish green, but sometimes it is more yellowish green with a reddish stem, as here. This exemplar is really big, it looms large above the tiny 'Controversial Sandworts' (Arenaria controversa) around it.

This year it is abundant, maybe because of the rain. Here some individuals from a carpet of thousands, each one with its flower head.