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(iii).-Regularity of cutting, by which I mean that the contractor should be bound down to begin from one end and cut progressively over the whole coupe to facilitate inspection and a large deposit, say 25 per cent. of his purchasemoney, was taken from the contractor, forfeitable upon breach of any of the conditions laid down.

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I think he would find that prices and consequently revenue would rise and work be done systematically.

I admit difficulty at first, but this, I think, could be overcome by a judicious combination of the suaviter in modo with the fortiter in re-probably at first more of the latter.

His coupes could be of any size, dependent upon demand and distribution. A three-year rotation has been found sufficient in Saharanpur, measurements and countings taken yearly showing there has been no diminution in girth or number. But the rotation would necessarily have to be fixed by extent of forest and demand. This method, too, would do away with the necessity of a long and probably more or less complicated price list, and would eventually lessen the work of Range officers. "S. E.-W.'s" last paragraph rather staggers me. I must say, with all due deference, that I have observed without exception that a mixed bamboo forest tends to become a pure one in time, reproduction being next to impossible. Fires would surely increase this tendency.

Of course there are different degrees, so to speak, of mixture; the more the bamboos, the stronger the tendency for the forest to become pure. The only chance for tree reproduction, and that a very poor one, would be when an extensive gregarious seeding took place, as for the first ten years or so the young bamboo attains no height, but in and about the eleventh year up shoot strong healthy culms, generally to the eventual exclusion and destruction of all other re-growth.

Lastly, are not pure bamboo forests self-protective, humanly speaking, long before 12 or 15 years? I would feel inclined to say-given, of course, perfect protection-8 to 10 years. I hope I have not too rashly rushed into print, but the system I advocate is what I am attempting to put into practice, with what success remains to be seen.

I hope more notes on the subject will be forthcoming to help us. I do not quite understand "Ghati" in the same number. He says: "I have substituted fellings a blanc étoc followed by artificial reproduction for the jardinage which I found in force." He then goes on to note the "additional revenue from pasture and fodder which follows."

Does he then allow grazing and grass-cutting, for both of which he says the demand is "enormous," in areas where he hopes for successful natural and artificial regneration ?

J

J. G. F.-M.

"S. E.-W." ON THE TREATMENT OF BAMBOOS.-A REPLY.

REFERRING to "Mavin Kai's" letter in Nos. 10-12 of the "Forester" for 1890, clause iv. of the Working Plan is correctly printed in my original notes. The cutting of immature stems is prohibited, and with proper supervision rarely occurs; thus the exporter has the certainty of finding the whole of the previous year's crop intact when he commences operations, and this certainly induces him to willingly offer large extra payments for the privilege of exporting from bamboo forests where the department has protected the immature crop. The form of pass in use under clause i. is a triplicate form, in which is entered the name of the exporter and the limits of the forest where he can work; one copy is given to the exporter, together with printed rules regulating the cutting, one copy is sent to the Divisional office for information, and one copy remains with the Ranger for reference. With regard to the price list under clause ii., the sale price of bamboos was formerly regulated by girth measurement. This naturally favoured the export of thin stems; the present system is to charge on length measurement only, which favours the cutting of the larger girth classes.

Since writing on this subject, I have had the opportunity of inspecting the bamboo forests of Bundelkhand, where the conditions of climate and soil vary considerabiy from those obtaining further north, the temperature being higher, the rainfall much less, and the soil poorer and more rocky. In result the bamboo of Bundelkhand does not possess such vivid green colouring as in the moister climate, and suffers much from forest fires, so that there fire-conservancy is evidently a necessity if we wish to preserve and improve the growth. I noticed considerable areas in which nearly every clump had been. destroyed by fire, and the rank growth of coarse grass following the annihilation of the bamboo gave every promise of future fires even more intense. In writing of fire-conservancy relatively to bamboo forests, it is, therefore, very evident that local details are all-important. The supposition that the solid variety of the male bamboo is chiefly induced by poverty and dryness of soil was strengthened by inspection of the Bundelkhand bamboo forests, these being exclusively located on the steep, well-drained, and

rocky slopes of these isolated hills and ridges, which are a so-well marked physical feature of this part of the N.-W. P. In the SubHimalayan forests the solid variety of bamboo is found on the hot and arid outer slopes, and rarely ever occurs in the cooler also moister valleys; but in Bundelkhand the very large proportion of the bamboo is solid even up to a girth of 8 inches. That wellregulated heavy cuttings result in good crops of new stems also received further proof, for the more inaccessible forests of Bundelkhand showed a marked deficiency in the number of shoots of the year, whilst the overworked accessible portions contained a fair number of immature stems, which, however, more rational treatment would certainly improve.

The haphazard mixture of age-classes was curious, and pointed clearly to the yearly seeding of isolated clumps. The proverbial oldest inhabitant stoutly denied the memory of even a very local general seeding, and apparently in this instance he was to be trusted. It is probable that protection from fire and other injuries and careful cutting will in course of time considerably lengthen the average life of a clump, and that in protected forests the objectionable seeding over large areas will occur more and more seldom ; it is, indeed, quite possible that in the future we may be able to regulate to some extent the seeding of bamboos so as to replace exhausted clumps by young growth as a result of natural reproduction. I have now no doubt that in the North-Western Provinces the bamboos from healthy and vigorous clumps arrive at commercial maturity in the second year. The stems are liable to many injuries if left standing longer, many are attacked by borers or destroyed by elephants, and, moreover, it is not at all certain that the lower side-branches of the bamboo do not continue to grow long after the parent stem has hardened; and if this is the case, the difficulty of extraction from the clump must yearly increase enor mously. Reliable information on this point would be gratefully received.

It will be most interesting to observe what effect the improvement of the quality of the bamboo will have on the revenue derived from this source in the Central Circle; supposing the demand for bamboo to remain stationary, it is evident that the export of an article of superior size and durability tends to lower the number of stems required by consumers, and in point of fact the numbers exported from this Circle are decreasing yearly, though the almost yearly rise in rates has hitherto resulted in an increase in the total revenue collected.

S. E.-W.

THE EXPLOITATION OF BAMBOO FOREST.

IN connection with the recent discussion on the working of bamboo forests, the following notes given to the students of the Imperial Forest School, Dehra Dún, may be found useful.

A great deal of attention has been paid to the subject, but as a rule observation has been confined to what occurs above ground, and the conclusions drawn therefrom have hence not been based on physiological principles. Such conclusions, being deductions only from partial facts, are often misleading, though true enough under certain conditions. For instance, "S. E.-W." has put forth the general statement that continued fire-protection is fatal to the maintenance of bamboos. Though true in some cases, such is not, however, the fact universally reference to physiology would have saved "S. E.-W." from falling into this error.

What goes on underground among the rhizomes requires much more study than it has hitherto received.

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MODE OF GROWTH OF BAMBOOS.

On emerging from the seed the bamboo seedling is a simple plant, consisting of a leafy shoot, fibrous roots, and a short, comparatively thick, intermediate portion, from which in the following year the first rhizome is developed. This rhizome at once grows up into a leafy shoot, and from this time forth the plant is a compound one and the formation and growth of the clump begins. In the third year one or more new rhizomes are produced from the "eyes or underground buds of the original rhizome, and every successive year, until the clump flowers, new rhizomes are similarly produced upon those of the previous year. As a rule, only a few of the eyes develop into rhizomes; but of the rest some may later on push forth under specially favourable conditions, as, for instance, when the existing number of unsprouted rhizomes is insufficient to utilise the entire quantity of constructive materials available in the clump.

According to the abundance of food present and the richness of the soil, one or more of the rhizomes produced upon the same parent rhizome start away at once out of the ground to develop into a leafy shoot (culm). Some of these shoots, owing to insufficient nourishment or accidental destruction, may become aborted after they have begun to develop. Thus aborted, they do not usually die, but their rhizomes, like those which remain dormant, may and often do give out new rhizomes, should accident place them subsequently under sufficiently favourable conditions.

Each successive year the new culms formed are taller and thicker than those of the preceding year, and this constant increase of size continues as long as the maximum dimensions attainable by the species in the given soil and locality have not been reached. After this period, save minor differences in different years due to the varying character of the seasons, the maximum dimensions are maintained until the clump fructifies and dies. It is hardly necessary to add that a culm cannot grow thicker, each part of it, as soon as it is fully formed, being as thick as it will ever be.

Since the rhizome has to form completely first, the culm itself does not appear above ground until some weeks of the growing season are past (in the case of full-sized culms not until towards the middle of the season), and it accomplishes the whole of its growth in 3-5 weeks, before it has put forth any leaves at all. Whence, we may ask ourselves, does it obtain the large amount of formative material necessary for such rapid growth? Having no leaves of its own while this growth is going on, and consisting, as it does, mostly of hard woody tissue, it can itself elaborate but little by means of its green superficial covering. The conclusion is thus inevitable that most of the requisite nourishment comes from the rest of the clump, and especially from those in closest connection with it, viz., (1) the parent culm and (2) that from which this latter has been produced (the grand-parent culm). This conclusion has been amply proved by numerous experiments. If the whole of a clump in full production is cut back, even during the season of repose, when the rhizomes contain their maximum amount of reserve materials, the new growth will not contain a single thick culm, but consist only of a dense mass of switches, proving the insufficiency of the supply of food to produce any larger growth. The falling off is more conspicuous the closer to the ground the clump is cut away, for the numerous branches which high-cut stumps throw out elaborate no inconsiderable quantity of food for the production of new shoots. It will be only gradually and after several years that the clump will again begin to produce full-sized shoots, the shoots of each successive year being bigger than those of the previous year, just as in the case of a clump developed normally from the seedling. This demonstrates another important fact, viz., that the larger the parent culms are, the larger, up to the limits of full size, will be the daughter-shoots. This same fact may be proved in a more direct manner thus :-Cut away all the thick culms by the base leaving only the switchy shoots, and the production of the following season will be entirely switchy; then, on the other hand, cut away everything except 1-3 of the large shoots, and in the

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