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once prosperous villages were covered with sand which laid waste upwards of 70,000 acres of fertile lands. By 1900 this formerly rich district was traversed by numerous broad, parallel, sandy belts, cut out of the fertile and crop-bearing area. Proofs of the advantages accruing from the strict protection of areas where erosion had resulted in annually increasing damage, with its many attendant consequences, were not therefore absent by the close of the century. In almost every instance protection from fire was almost immediately followed by the growth of a dense vegetation which soon checked erosion and reduced the danger of landslips and sudden floods; the beds of streams debouching from fireprotected areas soon began to contract in width and flow in narrower and better defined channels. Ribbentrop gives a number of other illustrations of the beneficial results obtained.
“A streamlet, the Mendikola, runs through the Mohwa Bir Reserve in Ajmere. A few years ago it was thirty feet wide where it leaves the forest block, but since the catchment area has been protected against fire the watercourse had gradually been confined to a distinct deep, narrow channel. Further below, where it is joined by small streams draining unprotected areas, the bed has maintained its original character. In the Central Provinces the smaller streams draining the Ahiri Forests, which were broad and rugged water channels, have, since the forests were protected from fires, entirely silted up, all but a narrow bed, and form part of the forest grown over with reproduction. The Sipna River (Bairagah Reserve, Berar), with its tributaries, which are crossed by the Ellichpur-Pili road, affords also a good example of the effect of fire conservancy in reducing floods, erosion, etc. Watercourses in the Siwaliks, between the Dehra Dun and the plains, have contracted to half, and even one-third, of their breadth under the influence of fire protection. Many have entirely filled up and exist now only as gentle, partly overgrown depressions.”
In 1899 Ribbentrop conducted Sir Thomas Holderness, G.C.B., lately Permanent Under-Secretary at the India Office and at the time Revenue Secretary to the Government of India, over this latter area. Throughout his long connection with Indian Administration Sir Thomas maintained a keen interest in and knowledge of forestry matters, and was responsible in no small degree for the progress of the Department. That his interest was of the practical kind the present instance records. Ribbentrop pointed out to him the results of fire protection in the forests clothing the Siwalik Hills, showing him many channels, surveyed and mapped as late as 1876, which had now ceased to exist, being overgrown by bushes and young sâl reproduction. In the case of the Ratamau basin, the sides and slopes of the hills were clothed with grass and young seedlings, and the water no longer rushed down carrying silt with it; the floods in the raus (streams) had as a result become reduced in volume and force, the water channels had become narrower and deeper, and the old beds were overgrown with grass and thousands of sissu (Dalbergia Sissoo) and khair (Acacia Catechu) seedlings. The little silt washed down was caught by the grass tufts, resulting in the elevation of banks in the stream's bed and the deepening and constricting of the water channels.
On the outer Siwaliks also fire protection had had the most beneficial results, and the upper courses of all raus, especially the Dholkhand rau, have been confined into permanent beds, and the smaller torrents which existed but a few years ago have filled up and to a great extent already form part of the new forest springing up. That on this side of the Siwaliks no adequate effect at the end of this period had yet been experienced in diminishing the freshets, which endangered the canal works, was due to the excessive grazing which still continued in the lower reaches.
Examples of this nature could be multiplied, and every Forest Officer at this period could have quoted object-lessons of the value of protection in his own charge which would have formed indisputable evidence.
The influence of continued protection on the continuity and supply of water in springs, tanks (ponds) and wells showed the most divergent results. In some places a continuity and regular supply of water followed protective measures, whereas in others an immediate decrease of the water supply took place. These phenomena had been foreseen. In the case of the tank, for instance, where the maintenance of the water level depended upon a rapid flow into it, which resulted from rain water falling upon and rapidly running off a bare piece of ground, a covering of vegetation on the area naturally interfered with this rapid flow. The tank had been built to replace the driedup streams and springs formerly existing on the area when it was covered with vegetation. These streams provided, naturally, moisture to the area which now had to be irrigated by raising the water from the tank by the labour of man and distributing it over the land. In the case of protective measures introduced with the object of restoring the natural water supplies, time is required before the sub-surface flow of water can regain its proper level, and the experiments made up to this time were still too recent to afford reliable results. Ribbentrop mentions, however, that water had already been found near the fireprotected Danta Reserve in Ajmere at a depth of fifteen feet, whereas under very similar conditions as regards rock, stratification and soil, but where the hill-sides were bare of vegetation, water was not reached under a depth of twenty-five feet.
During the next twenty years further definite evidence became available from the records of the Department on this subject, which will be treated of at a later stage in this history, as also the work which was commenced with the object of replanting some of these areas.
PROGRESS IN THE PROTECTION OF THE FORESTS
FROM PESTS With the very large amount of preliminary work to be carried through which faced the Department in its initiatory years, and in the absence at first of a trained staff and subsequently the comparative weakness in numbers of the trained staff, it is a matter of little surprise that but small progress should have been made during the period in the study of the pests—insect and plant—which affected the growth of the trees or depreciated the value or quantity of the timber and other marketable commodities of the forests. The preliminary work facing a new Department, the exploration of the forests, demarcation and survey, protection from fire, the regulation of grazing, opening out of communications, erection of buildings, and the exploitation of the marketable crops, often during the period done by departmental agency, occupied to the full the whole-time energies of the officers. Scant leisure was afforded them for carrying out the study even of the sylvicultural characteristics of the species they were dealing with. The diseases to which the trees were subject had to be left to a future time.
Insect Pests.—It is an interesting fact worthy of mention that enquiries on the subject of one insect pest, to which the name “Bee-hole borer” of teak had been given, were instituted
many years before. In consignments of teak “squares ” sent home to the Admiralty it had been at times found that on cutting up the squares in the mills the planks were found to contain elongated holes and blemishes which entirely ruined the timber for the purposes for which it was required. In his Report on the Teak Forests of Tenasserim, Dr. Falconer made the following allusions to this matter in 1851 : “The mixture of this light dead timber with unseasoned logs which have been felled green, and logs flawed with holes and clefts from the Thaungyin in the shipments made to England, is generally considered to have been the cause of the bad repute into which the Tenasserim teak has fallen at home for shipbuilding.
. . The two latter circumstances had more to do with the result than the first." ..." The tree during its growth does not seem to suffer much from the ravages of parasitical insects. Captain Tremenheere mentions that the stem is attacked by a beetle in the Thaungyin which bores teredo-like holes. I observed no marks of such an insect in the Attaran Forests.” Captain Guthrie, in a Report on the Tenasserim Forests in 1845, says: “Of the Thaungyin teak I may remark that I have seen it growing and thriving in every variety of locality; it has generally the advantage of carrying its girth well to a great height, not tapering quickly ; it appears to be somewhat liable to small cells, isolated, but which appear in the sawing up." Thus even in those early times an insect was known to be causing a serious loss in the teak forests. It was not a beetle nor a bee as events proved, but the destructive agent still remained an enigma at the end of the century.
Ramsay also reported the presence of borers which had not been as yet identified in girdled sâl in the NorthWest Provinces and Oudh sâl forests. The sytematic study of the fauna, especially the insects, in its relation to the damage committed in the forest, had not commenced. The scattered investigations and notes which had from time to time been recorded by observant Forest Officers were either published in the pages of the Indian Forester, entered in Divisional office or Range office diaries, from whose pages they rarely emerged, or were forwarded to the Indian Museum, Calcutta, when they appeared in Indian Museum Notes. Amongst the most interesting of the earliest recorded investigations of this nature, which appeared in the pages of the Indian Forester, were Mr. A. G. Mein's account of the “Kulsi Teak Borer” (Stromatium barbatum) which appeared in the Indian Forester, Vol. IV (1879), and reports of the teak defoliating caterpillars, Hyblaca puera and Paliga damastesalis, from Burma and elsewhere in India, by J. N. (1884) and others. The interesting series, Indian Museum Notes, was commenced in 1889 by Mr. E. C. Cotes of the Indian Museum and published by the Trustees. It dealt with economic entomology generally, and recorded such investigations as were sent to Mr. Cotes by Forest Officers, the former obtaining identification of the insects where possible. This question is dealt with in a later chapter.
Creepers.-Amongst plant pests, the creepers which infest the forests of India require a mention. In former parts reference has been made to the first protective work undertaken by the newly organised staff of the Department. This was the obvious necessity of clearing the trees from the giant creepers with which they abounded. It has been shown that in the Oudh forests this work was prosecuted on a systematic scale by the Conservator and his Assistants (p. 354), and references are numerous in the correspondence of the period to the thorough manner in which this campaign was carried out, and to the fact that funds were provided for the purpose. With the introduction of working plans, creeper cutting was laid down as an important operation to be effected in the
coupes," and was undertaken in the areas to be felled a year before the felling was to take place.
Fungous Pests.-If but little advance had been made in the study of the insect pests of the forests, the fungi of the forests and the damage committed by them remained a sealed book at the close of the century. The dry climate during the greater part of the year and the excessive flooding during the monsoon were not favourable to the growth of fungi in the plains part of the country. But the conditions were otherwise in the Lower Himalayan forests and in those of the hilly regions in other parts of India, and experts considered it probable that in these areas pests existed whose study would eventually prove of importance in the management of the forests. That the study of the fungi is a necessary branch of forest science need scarcely be commented upon. The work of German mycologists has sufficiently emphasised the fact. Their work however, it was considered, could only be drawn upon to a slight extent for practical application in India. Even when the parasites proved identical the trees on which they lived would be different, and consequently their mode of action would differ