dry that the winds carry it to a great distance. The smallest obstacle, such as a little hillock of soil, a tree, some tufts of broom, or of bent grass (arundo arenaria) are enough to stop the sand; it then accumulates much faster and forms larger heaps than when deposited by the waves, as the winds blow for a long time in the same direction. Such is the origin of the Dunes, of which the height and form vary like the conditions which have created them. Some are to be found from 20 to 30 and even 50 or 100 mètres in height.

"It is by a mixed system of wicker-work barriers and reboisement with maritime pines that the inroads of the sand which threatened the neighbouring communes have been nearly everywhere arrested; and it is one of the triumphs of the Corps des Ponts et Chaussées, to whom the Government entrusted this great and important work, and who have not only completed the undertaking, but they have by degrees improved and simplified the work and operations required, and have thus brought it within the power of any one to carry on similar work elsewhere."

To render intelligible to those who are unacquainted with the more advanced system of forest management followed on the Continent of Europe, the additional statements to be made, it may be well for me to state, that it differs considerably from the arboriculture which is generally practised in Britain, and from the Jardinage, and Sartage, practised in British Colonies and in the United States of America, and to supply here the following information in regard to it; and to repeat in substance what I have already said in speaking of the culture of the Scotch fir:

In the general management of forests on the Continent, in accordance with the most advanced forest science, three things are aimed at, and so far as practicable each is sought to be attained without detriment to either of the others: the sustained production, natural reproduction, and progressive amelioration of the forest. In prosecution of this there is determined, according as quantity, quality, or pecuniary profit may be mainly sought, at what age the trees shall mostly be felled. This in French is spoken of as the exploitability of the woods. But before this age is attained there are several successive thinnings executed, each with a special object, in accordance with which it has a specific designation.

The wood being the product of natural reproduction, or self-sown seed, there is often required a thinning out of the seedlings. This is known as the coupe d'ensemencem ent.

There may be required one or more successive thinnings as the

U

growth of the tree advances. These are known as coupes d'amelioration. There are subsequently thinnings executed to leave sufficient ground cleared and open for the reception of seed cast from the trees left standing. These are designated coupes de régénération. After which follows the final felling, or coup définitive, in which only trees required to give shade to the young seedlings, etc., are left standing. But there are exceptional cases, in which artificial sowing is deemed preferable. In these cases coupes de régénération are not necessary, and the coupe définitive takes the form of a clean sweep, known in technical phrase as la coupe à blanc étoc.

In regard to the treatment of the maritime pine, the instructions given at Nancy are in several points founded on those given in regard to the exploitation of the Scotch fir.

In these instructions we meet with the two terms coupes de régénération and coupe d'amelioration, in addition to the similar designations formerly explained. The former of these designations is applied to all the fellings or thinnings to which the forest may be subjected in the course of its reproduction; and the latter is applied to fellings or thinnings carried out with a view to the improvement of the forest in any way.

The corresponding instructions given in regard to the treatment of the maritime pine are these:

Exploitability.-To ascertain what size this tree may attain, and at what period its exploitability should be fixed, it must first be cultivated without any injury being done to its growth, for until we gain light from experience we can only judge by analogy.

"Trees which grow rapidly when young generally attain their maximum development sooner than do others. This is particularly true of the maritime pine. Nevertheless, in the south, where the climate is favourable, it continues to increase in size for a long time, and on this account it ought not to be exploited for 100 or 120 years, according to the nature of the soil, that the timber may acquire the desired solidity for building and other purposes.

"Of course, in adopting this revolution, gemmage is not permissible. Coupes de régénération.—The maritime pine never having as yet been subjected to systematic culture, the method to be followed is uncertain. But from the nature of the seed, the constitution of the young plant, and the arrangement of the roots, we may conclude that it ought to be exploited in the same way as the Scotch fir. At the same time, at the coupe d'ensemencement there may be left fewer plants as this pine is better able to resist the wind. Indeed, the seed is a

little larger and heavier than that of the Scotch fir, but the membraneous wing is also larger, which favours its dispersion to a distance. The secondary coupe will be unnecessary, on account of the hardy constitution of the young plant and the extreme rapidity of its growth, which lead us to believe that the coupe définitive should follow the coupe d'ensemencement as soon as possible, that is to say, in the year after the repeuplement, or within two years at the latest.

Coupes d'amelioration.—What we have said on this head regarding the Scotch fir, equally applies to the maritime pine. The first thinning should be expedited on account of the rapidity of its growth, and the intervals between those which follow should be abridged.

"The rules we have laid down for the exploitation are only applicable when the trees are not subjected to gemmage. When trees are to be gemmé these rules should be modified. For, on the one hand this operation diminishes the growth and shortens the life of the tree, and on the other it is not timber, but resin which becomes the chief product of the forest. The first circumstance renders much shorter revolutions necessary; the other, that the thinnings should be made at very short intervals, according to a method practised in the south of France, of which an account has been given.

"It being evidently the interest of the proprietor to hasten the period of gemmage as much as possible, it is of great consequence to promote the growth of the stem and summit in every way. For this end the young trees are thinned for the first time, at the age of seven, and afterwards the operation is repeated every six years until they are twenty-five years old, at which age they are supposed to have attained a suitable size. In these operations the pines are isolated by degrees. After the two first fellings the mass, although thinned, should still be preserved so as to promote the development of height; but after the third the number of trunks is reduced to 700 or 800 per hectare; and after the fourth only 500 remain; five years later these are again reduced to 400. The 100 trees doomed to fall in the fifth thinning are gemmés à mort, between the fourth and that, the others are gemmés à vie.

"These 400 pines remain standing from thirty to sixty years, and are gemmés every five years. At the expiry of sixty years, 100 trees are marked to be gemmés à mort, and are then cut down, while the 300 still remaining stand until the final coupe at the end of seventy or eighty years, sometimes of one hundred years, according to the state of the timber and the quality of the soil.

"We have already described how coupes de régénération should be

made. But it is believed that usually la coupe à blanc étoc, followed by artificial sowing, will be preferred. Indeed, in both systems the plough is indispensable, for, on account of the great distance between the pines, the ground cannot fail to be covered with all sorts of bushes and weeds; besides, the seed of the maritime pine costs very little and is easily gathered and winnowed, the quality is almost always good, and the sowings succeed well; everything tends to make the artificial way the preferable."

Both in the treatise by M. Eloi Samanos,* and in that by M. Amédé Boitel,t are given details in regard to the culture and exploitation of the maritime pine in Gascony, and in regard to the general culture of it elsewhere, additional to what has been given in this volume, inclusive of what relates to the gemmage or collection of the resinous sap, and the distillation and manufacture of the different products yielded by it.

* Traité de la Culture du Pin Maritime.

+ Mise en valeur des Terres Pauvres par le Pin Maritime.

CHAPTER XI.

DISEASES AND INJURIOUS INFLUENCES TO WHICH THE MARITIME PINE 18 SUBJECT.

SEOT. I.-Choking by an Over-growth of Local Vegetation.

BESIDES failures in the culture of the maritime pine, attributable to bad seed, and to unsuitable soil, it often succumbs to other injurious influences, which operate, not always singly and alone, but in combination, and one preparing the way for another. It suffers from cold, from hail, from snow, and from wind. When the tap-root comes upon a subterranean sheet of water, a layer of compact clay, or rocks somewhat coherent and continuous, it becomes covered with mosses and lichens, and it languishes, and dies; and yet subterranean aridity is not less opposed to its healthy growth.

In Sologne, where the natural shrubs are destructive to young seedlings, the precaution is taken of sowing the seed on newly cleared land; and recourse is had to some of the usages of husbandry, and the growth of annual crops, effective in themselves or their culture in cleaning the land, to destroy the noxious plants which might defile the ground to be converted into pineries.

M. Vilmorin has recorded that in his experience the couch grass, and some other of the grasses, such as the agrostis stolonifera, marsh bent grass, the holcus mollis, creeping soft grass, the agrostis vulgaris, fine bent grass, and many species of festuca, or fesque grass, may so take possession of the ground as to prove destructive to the young produce of sowings of pine trees; and in Sologne the growth of bromus, or brome grass, starves and kills the seedlings of the maritime pine, while in Gascony the broom is sown with this pine to shelter and protect it in infancy against the sunshine and the sea breezes; but there the seedling pines are stifled by a vigorous growth of heaths, such as the erica cinerea, the fine leaved heath, and calluna vulgaris, the ling or heather of Scotland.

SECT. II.-Destructive ravages by Birds, and Squirrels, and Insects.

Many birds, remarks Boitel, are destructive or injurious by eat