December 23, 1891.] 



Garden and Forest. 



609 



the-Valley racemes ; hence the popular name. Late summer 

 or early autumn is the flowering season, but it may be retarded 

 and prolonged for a considerable space of time by shading 

 from sunshine. C. arborea does not flower freely unless the 

 roots are well confined, and it can be induced to bloom when 

 comparatively small by attention to this peculiarity. Of 

 course, it must be supplied with food in the form of liquid- 

 manure. The foliage soon loses its refreshing green if the 

 soil about the roots is allowed to become dry, and it is the 

 lovely contrast of perfect flowers and leaves which gives the 

 plant its charm. Cuttings of firm young wood root easily in heat. 

 Phormium tenax. — This plant, well known as New Zealand 

 Flax, deserves a place among fine-leaved greenhouse plants. 

 It is without stem, and the straight leaves, bright green above 

 and glaucous on the under side, from five to six feet long and 

 two or three inches wide, appear in fascicles, radiating dis- 

 tichouslyfrom a common centre like the ribs of an extended fan. 

 The branched scape, bearing insignificant yellow liliaceous 

 flowers, is developed in summer, and exceeds the leaves in 

 length by about two or three feet. The foliage, however, is 

 the most attractive feature of the plant, and especially is this 

 true of the variegated variety. In the latter broad stripes of 

 yellow and white intermingle with the green of the leaves, 

 giving the plant a very pleasing appearance against a dark 

 background. There are several other forms of P. tenax, but 

 the species and this variety are perhaps the best for general 

 purposes. Both plants are very easily cultivated, and succeed 

 well in any house from which frost is excluded in winter. In 

 summer they thrive luxuriantly planted out in the garden, but 

 they must be taken up early in autumn. The species makes 

 the most vigorous growth in a rich sandy loam, but soil of a 

 comparatively poor character should be used for the variety, 

 by reason of its inclination to revert to the original green color. 

 A cellar frost-proof and fairly light will answer for the storage 

 of these plants in winter where there is no greenhouse. They 

 are quite at home in porches and entrances at any season of 

 the year, and when grown as house-plants they need no better 

 position. I once knew two specimens which had been grown 

 mainly in a hall-way for fifteen years. One was green, the 

 other variegated, and they occupied twelve-inch pots, without 

 a single change throughout all that time. They were placed 

 outside in front of the house a few weeks in summer, during 

 which time they received frequent doses of liquid manure 

 and a top-dressing of fresh soil. The remainder of the year 

 they spent in the hall at the bottom of a dark mahogany stair- 

 case, where they always looked well. No plant except, per- 

 haps, Aspidistra lurida, will survive more ill-usage than P. 

 tenax. The leaves are stiff, tough as leather, and therefore not 

 easily injured, and they are unusually slow to resent neglect in 

 watering. P. tenax was introduced to Ireland by a Mr. Un- 

 derwood from New Zealand in 1798. It is very common in 

 New Zealand, and its fibre is used by the natives in the manu- 

 facture notably of cordage. Considering the interest now 

 taken in Ramie and other fibre-yielding plants by Americans, 

 it is a matter of some surprise that P. tenax has not been tried 

 more largely. The fibre appears to be easily separated. In 

 1822 a company was organized for the purpose of cultivating 

 this plant in Ireland for its fibre, but the project had to be 

 abandoned on account of the slow growth made by the plant 

 under the climate of that country. 



Cambridge, Mass. 



M. Barker. 



Calanthes. — The season of these useful and brilliant Orchids 

 has come around again, and we are more pleased with them 

 than ever. The various tints of coloring of C. Veitchii con- 

 trast finely with the white varieties of C. vestita, C. ricbra and 

 C. occulata. A few plants set in between good specimens of 

 Adiantum Farleyense in the warm greenhouse have an excel- 

 lent effect. They take the eye at once, and give the house a 

 bright appearance while they last, which few other plants can 

 surpass. For cut flowers these Orchids are among the best. 

 Not many spikes of C. Veitchii, with fifty flowers and buds on 

 each, with Asparagus plumosus, say, for green, are needed to 

 make a centre-piece for a dinner-table that ought to please the 

 most fastidious. Florists ought to find profit in growing 

 Calanthes ; they increase rapidly, are no more trouble than 

 Roses ; they come into flower mostly after Chrysanthemums 

 have faded and gone, and would be valuable for the holiday 

 trade. They require an even temperature when in growth of 

 not less than sixty-five degrees at night and ten to fifteen de- 

 grees higher in the daytime. They grow best in a fibrous 

 loam, with a little thoroughly decayed cow-manure and a 

 sprinkle of sand to keep the mass porous. The pots should 

 be half-filled with potsherds, for thorough drainage is essen- 

 tial. The plants will bear feeding with liquid-manure after 



the fleshy roots have penetrated all through the compost and 

 the young bulbs begin to form. They must be shaded from 

 bright sun, and the long flower-stems carefully kept down 

 from the glass. 



A hundred plants in bloom at once, with fifty flowers and 

 buds on many of the stems, present a beautiful appearance, and 

 such a display can be seen now in the conservatories of 

 Mrs. J. W. Lasell in this town. 



Whitinsville, Mass. vY. S. 



The Forest. 



The Subjection of Torrents by Reforestation of 

 Mountains. — III. 



CORRECTIVE WORKS. 



'T'HESE may be considered as barriers, drains and rectifi- 

 *■ cations of the bed. 



The barriers, whether of dry masonry or of hydraulic mor- 

 tar, of timber or of living wicker-work, all have, as an object, 

 the enlargement of the section in such a manner as to ulti- 

 mately permit the establishment of a fixed and definite bed, 

 preventing all erosion, and giving a solid support to banks 

 otherwise unstable. Their deposits may be used to build up 

 the old bed, by forming a series of stairs across the channel, 

 and thus reducing as much as possible the great first cost of 

 dams. These secondary works, judiciously employed, may 

 even be retained among the greater works which it will 

 be necessary to maintain continually, and thus reduce the 

 number of the latter. The dams of the first class, besides 

 this principal function, have the effect (1) of breaking by thefalls 

 they produce the rapidity of the water-flow, and preventing a 

 sudden concentration in the main channel or in the river to 

 which the torrent is tributary, and (2) of holding back above 

 them the coarse material which formerly was carried into the 

 valley below. 



In addition to important works of the first class constructed 

 in the principal bed of a torrent, there are placed in all its 

 branches a series of rough barriers of rip-rap, so that the whole 

 upper basin is under control before a specific correction of the 

 channel is undertaken below. The value of this method, both 

 as regards economy and safety, has been sanctioned by nearly 

 twenty years' experience. 



The number of important works of the first order, their forms 

 and their dimensions depend upon the special character 

 of the torrent under consideration, and it sometimes happens 

 that the most powerful torrents require fewer great engineer- 

 ing works than certain others of an inferior development. 



So far as the rough barriers are concerned, experience has 

 shown that in many cases they may be widely spaced, espe- 

 cially in those places where the deposits are of rocky mate- 

 rial. In certain ravines the deposits have a slope of twenty- 

 five to the hundred, now held in place by vegetation. The 

 little wicker-work dams in the small ravines can only be em- 

 ployed where the slope is less than one to five. Covering the 

 bed of the channel with branches, or even with trees, piled two 

 or three meters thick, with the tops up-stream, has been sub- 

 stituted where the slope is steeper. This system, in'use about 

 eight years, has quickly furnished most valuable results in the 

 immediate correction of gullies. 



Drainage, cautiously tried at first, has assumed a great de- 

 velopment during the past ten years, since its effects have 

 proved so striking in some torrents.- These drains are 

 superficial and much ramified. They were first tried with the 

 object of giving the waters from melting snows or torrential 

 rains a rapid and immediate flow toward mains on the line of 

 the greatest slope, but they proved of greater and more 

 permanent value than their projectors had dreamed. The 

 earth, formerly unstable, wherever a corrected bed had first 

 made the base firm, was found quickly safe from saturation, and 

 the forestation of the bank or of the slope could at once be 

 proceeded with. Conclusive experiments have been made 

 during the past few years over an area of about 5,000 acres, 

 which are to-day dry and solid. 



The practice of rectifying the beds of torrents after a pre- 

 liminary treatment has been largely developed, especially 

 where the transverse profile of the torrent presented a suitable 

 width and the longitudinal profile a pitch not exceeding twelve 

 or fifteen to one hundred. The treatment consists of ranging 

 at the foot of the banks rocks which will ward off the current 

 and thus form a good defense for the shore. The new bed 

 once outlined thus, is fixed by means of rude walls of large 

 blocks, tending to guide the waters in the desired direction and 

 checking all erosion, whether lateral or longitudinal. This 

 very economical method requires continued attention for a 



