Cabomba 



( 149 ) 



Cactus 



Gall Weeril (Ceutorrliyni'iis sulcicollis). Various 

 members of the Brassica tribe suffer through this 

 pest. The insect is fully developed early in the 

 summer, and deposits eggs on the lower portion of 

 the stem, beneath the ground. The grubs feed on 

 the soft part of the stem and the main roots, and the 

 irritation causes galls to appear. If these are cut 

 open they are found to contain white grubs. Gall 

 Weevil is often confounded with Club Hoot. After 

 removing the crop, dress the ground in the autumn 

 with gas lime, at the rate of 1 peck to the square 

 rod (30} square yards), or quicklime at the rate of 

 1 bushel to the rod. Allow either to remain on 

 the surface a few weeks before digging in. Avoid 

 planting a similar crop on the same ground the 

 next season. Kemove the galls from the stems of 

 affected seedlings, and dip the plants in a puddle 

 of soot, lime, chiy, and water. Scatter sand, in 

 which p.'inillin has been soaked, among the plants 

 in the seed bed. 



Club Jiaut (Plasmodiophora liraalcre). Anbury, 

 Club Hoot, and Finger and Toe are names by which 

 this destructive fungoid disease is known. A slight 

 swelling of the root is the first sign of the fungus, 

 followed by a knotted, club-like appearance, which 

 prevents the roots from performing their functions, 

 and the plant collapses. When the disease is in 

 an advanced state the roots become very much 

 contorted, and a mass of rottenness. After the 

 decay of the roots, the spores are liberated, and 

 remain in a resting state in the soil for one or 

 two years. This should be borne in mind, and no 

 crop liable to the fungus grown on the infested 

 ground for a few seasons. Burn all diseased stems 

 and roots. Apply gas lime in the autumn, and 

 quicklime at the rate recommended for Gall 

 \\Yrvil. Dip the roots and stems, before planting, 

 into a puddle of lime, soot, clay, and water. Burn 

 all specimens that betray signs of the disease. 

 Avoid light, sandy soil if possible. Earth up the 

 Mrm> when the plants are half grown, to encourage 

 surface roots. 



CABOMBA. 



A. genus of small aquatic plants with yellow 

 (lowers (ord. NyrnphaeaceEe), which are mostly 

 suited for growing in the greenhouse in summer 

 and in a cool place in the stove in winter. They 

 require water about 1' deep, with 2" or 3" of good 

 soil in the bottom. The principal species is 

 aquatica. 



CACOUCIA. 



Tropical climbing shrubs (ord. Combretaceae), 

 characterised by terminal racemesof bright-coloured 

 flowers. Propagation is effected by cuttings of 

 half-ripened shoots, and other cultural require- 

 ments are met by a warm, moist house, and a 

 mixture of peat, loam, and sand. 



Principal Species : 



coccinea, My., sc. 



CACTUS. 



Description. A name often applied collectively 

 to the various genera of Cactese. The family is 

 confined to the arid desert and mountainous 

 regions of the warmer parts of America and 

 aili;ii-i.nt islands, though some species have become 

 naturalised in other countries. The chief charac- 

 teristics of the order are readily noticed, both in 



Cacalia (see Emilia and Senerio). 



habit and flowers. All come under the heading of 

 shrubs or small trees, and are distinguished by 

 succulent, curiously angled, or flattened stems 

 which in most cases are leafless and multitu- 

 dinous clusters of fine, sharp hairs or bristles, as in 

 Opuntia and Mammillaria ; or long, stout, horny 

 spines or flattened hooks, as in Cereus and Echino- 

 cactus. They vary to a great degree in habit, 

 some of the dwarf Mammillarias being barely 1" 

 high and having the stems crowded together in 

 large, cushion-like masses. Others, as in Echino- 

 cactus, make large, globular stems, 18" high ; 

 while some Cereuses make single columnar stems 

 20' or more in height. Opuntia and Phyllo- 

 cactus are quite different again, by reason of their 

 flat branches. The flowers are remarkable on 

 account of the large number of highly coloured 

 sepals and petals, which in many instances are 

 very much alike. The stamens are thread-like, 

 indefinite in number, and fall to one side of the 

 flower. The fruits of several species are edible, 

 the best known being the Indian Fig (Opuntia 

 Ficus - indica). In tropical and sub-tropical 

 countries the stronger Opuntias are used as hedge 

 plants. 



Propagation is effected by means of seeds, 

 cuttings, division, or grafting. Seeds should be 

 sown in a mixture of loam and leaf mould, to 

 which has been added an equal bulk of sand and 

 small crocks, pots being used which have pre- 

 viously been half filled with crocks. Cuttings may 

 be made of any portion of a stem, and they must 

 be dried in the sun for several days before insertion 

 in a similar compost to that used for seeds. In 

 cases where plants make dense tufts of stems, 

 division at the time of potting may be tried. In 

 a few instances grafting is resorted to, the 

 method known as " inverted saddle " being adopted. 

 A house with a minimum temperature of 60 and 

 a dryish atmosphere, is well adapted for prop- 

 agation. For small seedlings and unrooted cuttings 

 very little water is necessary. 



Soil. Good fibrous loam should form the founda- 

 tion of the potting material. To an equal bulk of 

 this should be added sand, broken sandstone, or 

 brick rubbish. Pots should be filled to a depth of 

 one-third with drainage, and the soil pressed firmly 

 about the roots. During March and April is the 

 best time to pot. If a rockery is made and the 

 plants are planted out, better results are obtained. 



Other Cultural Points. Water is given in 

 summer, but less than is supplied to other plants. 

 After August the supply must be gradually with- 

 held until the end of September, after which time, 

 with one or two exceptions, little or no water will 

 be required until spring. Modifications of this 

 treatment will be mentioned with each genus 

 when necessary. 



Principal Genera : 



Cereus. 



Echinocactus 



Epiphyllum. 



Other Genera : 



Echinocereua (see Ce- 

 reus). 



Echinopsis (see Cereus). 



Eriosyce. 



Melocactus. 



Mammillaria. 



Opuntia. 



Phyllocactus. 



Nopalea. 



Pelecyphora. 



Pereskm. 



Pilocereus (see Cereus). 



lihipsalis. 



For particulars see each genus. 



Cactus Uahlia (see Dahlia). 



