THISTLE. 



THORN. 



mw). The principal biennial thistles are the 

 spear or bull-thistle (C. lanceolatus), the marsh- 

 thistle (C. palustris), and the cotton-thistle 

 (Onopordum acantheum). The perennial species 

 are two, the common sow-thistle (Sonchus ar- 

 tenm), and the common or field-thistle (Cnicus 

 arvensis), or Canada thistle. The dwarf or 

 stemless thistle (C. araw/is), the star-thistle 

 (Centaurea calcitrapa), and the common carline- 

 thistle (Carlina vulgaris), are more frequently 

 found to infest dry sandy pastures and calca- 

 reous soils than loamy or damp grass-lands. 

 Where they prevail to a great extent, there is 

 no remedy like breaking up the land and taking 

 a course of crops ; for palliative remedies are 

 of little avail. Hand-weeding, when the weeds 

 are confined to local spots, and are only just 

 beginning to spread generally over the soil, 

 will be found effectual ; but when once the pas- 

 ture becomes generally infected with the seeds 

 and roots of these plants, no time should be 

 lost in using the plough, harrow, and horse-hoe, 

 and a judicious course of cleansing crops be- 

 fore returning the land again to permanent 

 pasture. 



Among the species of pasture-weeds that 

 generally prevail in loamy soils, and are also 

 prevalent in clayey and damp soils, are the 

 marsh or red plume-thistle (Cnicua palustris), 

 the meadow or small purple plume-thistle 

 (Cnicus pratensis), and the melancholy plume- 

 thistle (Cnicus heterophyllus). In crops of artifi- 

 cial grasses, such as sainfoin, lucern, &c., 

 where the dwarf plume-thistle (Cnicus acaulis) 

 prevails, and when it is impracticable, under 

 such circumstances, to draw out this weed 

 without injuring the crops, a good remedy will 

 be found in the use of common salt. Children 

 may be employed to apply the salt by hand to 

 the crown of the weed. If the least part of the 

 root of the thistle be left, it springs up season 

 after season. Besides possessing this principle 

 of vitality in the root, its seeds are so winged 

 with down as to render dissemination, even to 

 a great distance, by means of the wind, almost 

 certain. 



It is obvious that the annual and biennial 

 species of thistles may be readily removed by 

 preventing their running to seed and dissemi- 

 nating themselves, which is best effected by 

 carefully eradicating them, or frequently mow- 

 ing them over close to the surface, and rolling. 

 But in the perennial kinds, from their roots 

 continuing in the earth, increasing and throw- 

 ing out new shoots or stems every year, there 

 is much difficulty in extirpating them, and they 

 perhaps can be no other way destroyed than 

 by rooting them out of arable land by deep 

 ploughing and frequent harrowings, or by fal- 

 lowing or laying the land down to pasture ; the 

 annual species seldom appear in pasture-lands. 

 But for destroying the common thistles the best 

 method is by weeding-pincers, or the finger and 

 thumb when in loose land, cutting them over in 

 the bleeding season frequently by weeding- 

 knives, and applying salt to the cut stalk. 



The most common thistle found in the United 

 States is the C. lanceolatus, a biennial. The 

 most troublesome pest, the C. arvensis. (See 

 CANADA THISTMJ.) Dr. Darlington thinks the 

 yellow thistle a foreigner introduced into the 



United States. It is the most prickly of all 

 the tribe, and hence called by botanists Carduus 

 spinosissimus, and Cnicus horriduus. The root 

 of this is considered by some biennial, by others 

 perennial. The tall or tallest thistle (C. altissi- 

 rm/s), is common along fence-rows, &c., in the 

 Middle and other States. The dwarf carduus 

 (Carduns Pujj7i),is common in Pennsylvania 

 and other Middle States, growing in old fields, 

 &c., from 1 to 2 feet high, with flowers of a pale 

 reddish-purple, and quite fragrant. The heads 

 are handsome, and the largest of any other 

 American species. Several other species of 

 thistle are found in the United States. See 

 CANADA THISTLE. 



THISTLE, PLUME (Cnicus"). This is a 

 separation from the genus Carduus made by 

 Sir J. E. Smith. They are prickly, herbaceous 

 plants, and differ chiefly in the down being 

 evidently feathery, not merely rough. The 

 biennial species may be readily destroyed by 

 mowing before the flowers form seed. There 

 are in England nine indigenous species of 

 plume thistle. Some of which are common, in 

 waste ground, moist meadows, &c. Those 

 which give most trouble to the farmer are, the , 



Marsh plume-thistle (C.palustris), a biennial, 

 growing plentifully in moist meadows or pas- 

 tures, and watery spots by road-sides. Stem 

 from 3 to 6 feet high. 



Creeping plume-thistle (C. arvensis). A very 

 troublesome perennial weed in cultivated fields 

 and by way-sides, from its fleshy root, which 

 is very tenacious of life, creeping deeply into 

 the earth to a great extent. Stems 3 or 4 feet 

 high. 



Branching bog plume-thistle (C. Forsteri). A 

 perennial, flowering in July and August, with 

 a tapering root. 



Woolly-headed plume-thistle (C. eriophorus). 

 A large and conspicuous perennial plant, grow- 

 ing in waste mountainous ground, and by road- 

 sides, on a limestone or chalky soil. 



Melancholy plume-thistle (C. heterophyllu*'). 

 A perennial, growing in moist mountain pas- 

 tures in the north. 



Meadow plume-thistle (C. pratensis). A pe- 

 rennial, growing in low, wet meadows and pas- 

 tures, especially among trees. Root fibrous. 



Dwarf plume-thistle (C. acaulis). A peren- 

 nial, growing on chalky and gravelly soils. 

 Root woody, running deep into the ground. 

 Stem entirely wanting. The large bright-green 

 leaves, spreading close to the ground, in a 

 circle near a foot in diameter, choke all other 

 herbage. 



THORN (CVategw*). A name given to 

 several indigenous shrubs and small trees. 

 See BLACK-THORN, BUCKTHORN, HAWTHORN, 

 WHITTUOHN, &c. 



Of this genus of shrubbery trees so valuable 

 in an agricultural point of view, there are 

 many species and varieties. Dr. Darlington de- 

 scribes the folio wing as found in Chester county, 

 Pennsylvania* 1. The Newcastle or cockspur 

 thorn (C. crus galli). Two varieties of this exist, 

 the most common of which is much employed 

 in making the fine hedges for which New- 

 castle county, Delaware, is celebrated. Dr. 

 Darlington thinks that, with proper manage- 

 ment, this kind will ultimately make a more 



1035 



