CAN 



[189] 



CAN 



into it. In all cases it is the best prac- 

 tice to remove the tap root. If the trees 

 are planted shallow, as they ought to 

 be, and the surface kept duly fertile, 

 there is not much danger of the roots 

 striking into the worse pasturage of the 

 subsoil. 



Scrubbing the bark of the stem and 

 branches with a mixture of soapsuds and 

 urine, and, where any pruning has 

 taken place, keeping the wounds covered 

 with a mixture of clay and cow-dung are 

 the best local applications. "We once 

 thought resinous plasters the best, but 

 subsequent experiments have altered 

 our opinion. 



The canker in the auricula is a rapidly- 

 spreading ulcer, which, destroying the 

 whole texture of the plant where it oc- 

 curs, prevents the rise of the sap. Some 

 gardeners believe it to be infectious, and 

 therefore destroy the specimen in which 

 it occurs, unless it be very valuable ; 

 but this we believe to be erroneous, the 

 reason of the disease appearing to be 

 infectious, or epidemic, being, that it oc- 

 curs to many when they are subjected 

 to the same injurious treatment. 



It appears to be caused by the appli- 

 cation of too much water, especially if 

 combined with superabundant nourish- 

 ment. Therefore, although cutting out 

 the decaying part, when it first appears, 

 and applying to the wound some finely- 

 powdered charcoal, will effect a cure if 

 the disease has not penetrated too deeply, 

 yet it will be liable to return imme- 

 diately if a less forcing mode of culture 

 be not adopted. No auricula will suffer 

 from this disease if it be shifted an- 

 nually, and the tap root at the time of 

 moving be shortened ; a thorough system 

 of draining being adopted, and excessive 

 damp during the winter being prevented 

 by proper shelter. 



Parsley grown in a poor soil is also 

 liable to canker in the winter. Mr. 

 Barnes says he never found any appli- 

 cation which eradicated this disease so 

 effectually as a mixture in equal parts 

 of soot and slacked lime, thrown over the 

 plants. The cure is complete in a few 

 days, the vigour of the plants restored, 

 indicating that this species of ulcera- 

 tion arises from deficient nourishment. 



The tubers of the potato also are 



liable to the speck, black spot, or canker, 

 a disease which we once thought occa- 

 sioned by the calcareous earth, lime, or 

 chalk, contained by the soil ; but on more 

 lengthened observation, we find it in all 

 soils, and in seasons characterised by 

 opposite extremes of wetness and dry- 

 ness ; hence we are induced to consider 

 that the disease arises from some defect 

 in the sets employed, or to potatoes 

 being grown too often on the same site. 

 It is quite certain that in ground tired 

 of potatoes the disease most extensively 

 appears. This suggests that it is occa- 

 sioned by a deficiency of some consti- 

 tuent in the soil, a suggestion confirmed 

 by the fact, that in the fields of the 

 market-gardeners near London, which 

 are supplied without stint with the most 

 fertilizing manure, this disease of the 

 potato comparatively is unknown. 



The stems of succulent plants, such as 

 the cacti, mesembryanthemums, and the 

 balsam, as well as the fruit of the cu- 

 cumber and melon, and the stalk of the 

 grape, are all liable to canker in some 

 form. 



CA'NNA. Indian Shot. (The Celtic 

 name for a cane, or reed. Nat. ord., 

 Mar ants [Marantaceas]. Linn., 1-Dian- 

 dria, \-Monogynid). Stove herbaceous 

 perennials. Divisions of the root ; seed 

 sown in hotbed ; rich open loamy soil. 

 Summer temp., 60 to 80; winter, 50 

 to 55. 



C. achi'ras (Achiras).) 5. Dark red. August 

 Isle of Mendoza. 1829. 



angustifo'lia (narrow-leaved). 2. Scarlet. 



April. South America. 1824. 



auranti'aca (orange). 4. Orange. De- 



cember. Brazil. 1824. 



ca'rnea (flesh-coloured) . 4. Flesh. De- 



cember. Brazil. 1822. 



cocci' nea (scarlet). 2. Scarlet. December. 



South America. 1731. 



compa'cta (compact). 2. Red. April. 



East Indies. 1820. 



crrfcea (saffron-coloured) . 2. Red. May.;i823. 



denuda'ta (naked). 2. Scarlet. June. 



Brazil. 1818. 



latifo'lia (broad-leaved). 3. Red. 



May. Brazil. 1818. 



di'scolor (two - coloured - leaved] . 10. 



Scarlet. November. Trinidad. 1827. 



edu'lis (eatable). 3. Red. September. 



Peru. 1820. 



esculcfnta (esculent). 4. Red. December. 



South America. 1822. 



exctflsa (lofty). 16. Scarlet. January. 



Brazil. 1820- 



fla'ccida (weak). 5. Red. July. South 

 Carolina. 1788. 



