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dwarf thistle

Значение термина dwarf thistle в knolik

dwarf thistle - Dwarf thistle (Carduus acaulis)
dwarf thistle - There was no mistaking it. Thistles of all sorts there were in plenty around: Musk Thistles, a couple of feet high with great, lovely, drooping heads of rich purple, formed a striking group; Creeping Thistles, apparently belying their name, stood still higher, and showed ominous teeth round their single-sexed flower-heads, the males round, the females more oval; Carline Thistles, rivalling the Creeping Thistle in prickliness, were unique with their yellow shining rays - but the Dwarf Thistle, little as it was, held its own and caught the eye on those chalky, spreading Downs. Like so many small islands dotted about over the green sea of the close turf, its rosettes of leaves lay, each like a many-rayed star, close pressed to the earth, each ray a single leaf radiating from one central point, the point where the thick root entered the ground. The ray-like character was emphasised by the pale midrib which ran down the centre of each leaf, while the design was elaborated and decorated by the fact that the margin of the leaves was cut into great teeth right down to the aforesaid midrib, each of these teeth being itself jagged and toothed again, and every ultimate green tooth ending in a sharp, colourless spine. "Surely Mars rules it, it is such a prickly business," one echoed Culpepper as one looked down on the plant; but nevertheless there was great beauty of design in every one of those thistle-leaf islands when one came to consider them.

In the centre of each of the rosettes a number of buds and flowers in all stages stood erect on the shortest of stalks, and formed a brilliant red-purple centre to the green star. The earliest stage was represented by a flower-head bud rather like a green, cupless acorn, with an outer coat of many overlapping scales; an older stage had a flat, white top faintly tinged with purple because the coat had opened and disclosed the light tips of a multitude of feathery hairs and lilac tubes, all tightly pressed together and held in place by the aforesaid coat. A still later stage showed at one point a little ear where several of the purple tubes had suddenly shot up beyond the others, and so in successive stages the number of these rapidly increased until the full-blown Thistle was presented.

If one had rooted up one of these Dwarf Thistles - and the deed is not to be cavilled at, for in spite of their attractiveness they are all pests that take up space and kill the turf beneath - and with a sharp knife had slit right down through the flowering Thistle-brush, this is what one would have found, turning it round and about: firstly, that the coat of green, overlapping scales had no sharp points, and so the head could be handled with pleasure, which is more than can be said of many of the Thistle-heads; secondly, that some eighty to a hundred long, slender florets were set on a hard receptacle or platform. If one or two had been isolated and laid side by side, one would have discovered a little cream-coloured ovary at the base of each, and on it a ring of many silky white hairs, three quarters of an inch long, maybe, standing round a gleaming white tube no thicker than a pin. Above the hairs, however, the tube had swelled a little and also become a red-purple, its top being fringed into fine, erect segments. Honey lay invitingly in the depths. Inside the tube, fine though it was, was a still finer one formed by the heads of the five stamens, and through this, in due time, pushed, like a piston, a red-purple rod clothed with hairs, thrusting before it white pollen grains. In some of the florets the silvery ball of pollen could have been seen lying just on the top of the anther tube - the anthers, by the way, having opened on the inside and discharged their contents into the tube. Matters had been carried a stage farther in florets on the outer ring of these, for the style-piston had grown and thrust the pollen ball off its perch on to the adjacent florets, or, perhaps, the ball had been removed by the body and legs of those many bees and flies that specially favour Thistle flowers, and in their visits smear the pollen from one floret to another, or carry it bodily from one head to another. As the style was completing its growth the stamen filaments contracted, and so the anther cylinder was drawn back into the corolla, thus the stylar column was left bare beyond the petal tube. It then forked into two branches roughened with papillae, and these stretched out waiting for pollination. Later they curved over and touched the sweeping hairs, and thus might have been self-fertilised by any pollen grains still clinging to them.

If we had then turned from our dissected head to its whole neighbour we should have seen how the florets wither and the petal tubes fall away, though the little one-seeded ovaries with their crown of silver hairs still retain their hold on the hard receptacle within the enfolding green bracts. But in still older flower-heads we should have discovered how at length even their hold slackens and their silvery hairs spread a little and assert their true role of parachute; on older heads in the sunshine the fruits would be making their escape, asking but the merest movement of the air to carry their feather-weights -

"Thistle beard
That skimmed the surface of the dead calm lake,
Suddenly halting now - a lifeless stand!
And starting off again with freak as sudden,
In all its sportive wanderings, all the while
Making report of an invisible breeze
That was its wings, its chariot, and its horse,
Its playmate, rather say, its moving soul."
(Wordsworth.)

But it is not to be imagined that the Thistledown so often seen floating is necessarily carrying its seed burden, for more likely than not it is a parachute that has lost its passenger. So lightly attached is the seed that a little jar against a branch, a leaf, or what not, or even an extra gust of wind, will detach it, leaving the feathery hairs to sail on, though their work is accomplished. It must be noticed that these hairs are each feathery, a point of apparently little moment, but one on which the botanist lays stress as a basis for classification, those Thistles with a "feathery pappus" being said to be in the group Cnicus, those with simple pappus (plain hairs) being Carduus proper.

The Dwarf Thistle is essentially a plant of chalky downs and open heaths. Its flowers are found in July, August, and September, and, with all the other eleven kinds of Thistles that plague our farmers, it is classed in the great family of the Compositeæ. Its root is particularly thick and woody, and was at one time chewed as a remedy for toothache.

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brother wort

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