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P L A 



THE UNIVERSAL HERBAL; 



P L A 



Suffocatio incrementi, is a sterile or weak growth, the leaves 

 become pale, and smaller, and at last the whole plant decays. 

 It is different from consumption in this, that the causes of it 

 are only accidental, and may be removed, so that the plants 

 may still recover. Bad growth is occasioned by parasitic 

 plants, twining plants, and too glutinous a soil. When those 

 impediments to growth are removed, the plants will soon 

 recover. Exulceratio, is a corroded part of a plant, from 

 which proceeds an ichorous filthy water. It takes place after 

 wounds which are not properly taken care of, or which 

 have such an unfavourable situation, that rain or snow may 

 stagnate in them. Farther, it is produced by insects, or 

 spontaneously by unknown causes. No ulcer heals of itself 

 in plants ; it is more or less destructive, the slower we are in 

 bringing assistance. All ulcerated parts ought to be taken 

 off, and the sound parts covered with a coating of grafting 

 wax, or of Forsyth's cement. An ulcer often corrodes wood, 

 pith, or other parts of trees, from neglect of the gardener; 

 in this case, all that is affected, must, without loss of time, 

 be cut away, and, as just now mentioned, the access of mois- 

 ture must be prevented by the application of some grafting 

 wax or cement. From unknown causes, the bulbs of Hya- 

 cinths and other fleshy roots exulcerate. We must endea- 

 vour to effectuate their cure by putting them in a dry place, 

 taking off the diseased part, and covering it with cement. 

 However, we rarely succeed, as the bulbs are mostly destroyed 

 to the very centre. The best remedy for plants is the graft- 

 ing wax, if well prepared ; but in many cases, especially for 

 large wounds, Forsyth's cement, for the receipt of which the 

 king of England paid 15,000 dollars, is by far preferable 

 to the former. It consists of sixteen parts of cow-dung, 

 eight parts of dry lime taken from an old building, as much 

 charcoal, and one part of sand out of a river, which are to 

 be mixed together into a thick salve. In place of cow-dung, 

 ox's blood, and instead of lime, dry chalk, may be employed. 

 This cement is to be spread thinly on the affected part, and 

 to be rubbed with a powder, consisting of six parts of char- 

 coal, and one part of the ashes of burnt bones or carbonate 

 of lime, till the surface of the cement is as smooth as if 

 polished. Forsyth did wonders with this preparation, and 

 cured with it all wounds of plants without any further trouble. 

 It does not keep well, and therefore only as much of it must 

 be prepared, as is wanted for the time, or, if it is to be pre- 

 served, it must be sprinkled with urine. It should further 

 only be applied during dry weather, by which means it covers 

 the wound with a cortex. Rafn asserts, he had experienced 

 the same good effects from a mixture of pounded coal and 

 potatoes, or some other soft substance, and even prefers this 

 to Forsyth's mixture. Carcinoma arborum, or a cancerous 

 affection, occurs principally in fruit-trees, when they lose 

 too much gum, and this undergoes an acid fermentation. 

 This disease appears frequently in low-lying gardens after 

 deluges. A great spongy excrescence rises, which even in 

 the driest weather discharges an acrid ichor, which corrodes 

 every thing. We distinguish two species, the open and the 

 latent cancer. The first species is easily seen, and cured 

 by simply extirpating the affected part. But the second 

 species may have spread far in length, and under the cortex, 

 before it is discovered. We must then hasten to save the 

 tree, and, after removing the wounded part,' apply Forsyth's 

 cement to it. To obviate this disease, we must improve the 

 station of the plant, and endeavour to prevent too much 

 formation of gum in fruit-trees. Necrosis, or dry gangrene, 

 is that disease which causes the leaves or other parts to 

 grow black and dry. It arises from late night-frosts, severe 

 cold in winter, burning heat, suppuration of the sap in single 



branches, and by smaller plants. Late night-frosts, very 

 frequently kill young shoots of plants, which therefore grow 

 black, and shrink. No other preservative can be used 

 against this than covering young plants as soon as cold nights 

 may be dreaded. Some assert, that they have derived great 

 advantage from conductors of frost, which consist of a com- 

 pactly twisted cord of straw, directed into a vessel with 

 water. From severe winter cold, foreign trees suffer chiefly, 

 and such of our native plants as are very delicate. Their 

 inner bark freezes, becomes black, and it is impossible to 

 save them. All the wounded part must be clipped, and the 

 main trunk with the roots only be allowed to remain, to 

 produce new shoots. Intense heat will produce the same 

 bad effects in gardens, or even in forests, where foresters 

 are permitted to remove the mosses and dry leaves from the 

 roots. Single branches sometimes, by the too rapid growth 

 of others, are deprived of their necessary food, and wither 

 away. This may happen without any injury to the plant. 

 Small fungi occasion this disease in the bulbs of the Saffron; 

 it is a nuredo which destroys them. On the Gold coast of 

 Africa, a wind blows called Harmattan, which kills the 

 plants, making their leaves dry and black. Gaiigr<ena. 

 Plants affected with gangrene become soft and moist in some 

 single parts, which at last dissolve in a foul ichor. It chiefly 

 attacks fruits, flowers, leaves, and roots, rarely the stem. 

 Gangrene arises either from too moist or too fat and luxu- 

 rious ground, from infection and contusion. It scarcely 

 admits of a cure, as it infests only single parts ; but if 

 the causes which give rise to it are removed, it may be 

 prevented. Ustilago, appears especially in the species of 

 gramina and grain ; rarely in other plants ; sometimes in 

 Scorzonera, Tragopogon, &c. It arises from a small fungus, 

 which occupies the whole ear, which therefore cannot evolve. 

 Every part of it, on the contrary, becomes a black soiling 

 mass. Moist seasons are most favourable for its evolution, 

 and its formation is, under such circumstances, very rapid. 

 That corn may not be affected with it, such grain only 

 should be sown which has not been kept in damp places, 

 nor has been got from where the disease prevailed. It is 

 natural to suppose that the infection would by such means 

 be propagated. Neither should the grain be placed too 

 deep in the ground, especially where the soil is very fat or 

 moist. When, however, it is once begun, the plants dis- 

 eased cannot be cured. In tender and scarce garden plants, 

 something may be done, by amputating the diseased part 

 before its perfect formation. But in general, this expedient 

 is not advisable. Mutilation, happens especially in flowers, 

 and the name flos mutilatus is used, when single parts of a 

 flower, particularly the corol, are not come to perfection. 

 The causes of this mutilation are unfavourable climate, and 

 improper soil. Flowers, notwithstanding this mutilation, 

 often bear perfect seeds. The species of violet, Viola oclo- 

 rata and canina, often produce in our climate, if the wea- 

 ther is not warm enough, flowers wanting the corols. Cam- 

 panula hybrida has here no corols, but is said to have them 

 in France and Italy. In several of the campanulate flowers 

 we see frequently the corol wanting ; for instance, in Cam- 

 panula pentagona, perfoliata, media. Some other plants, 

 as Ipomoea, Tussilago, Lychnis, are liable to the same acci- 

 dent. Ruellia clansdestina is thus called, because it has 

 sometimes flowers without the corols, sometimes with them. 

 The same is said to be the case in its native country, Bar- 

 badoes. Hespe-ris matronalis, during long-continued moist 

 weather, from superabundance of food, frequently bears 

 blossoms, where the corol becomes a second calix. The 

 Dianthus caryophyllus augments the scales of its calix so 





