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lobed or notched, while those of the mature tree are entire; and the contrary. The greatest variations in point of form are, perhaps, to be found in individuals of the group Nigræ; and the greatest in point of colour, in the group Rubræ. As a painter's tree, valued for its picturesque effect, when near the eye, no species equals the Q. pedunculàta; but for general effect, at a distance, at least in America, the American oaks, the leaves of which die off of a deep red or fine scarlet in autumn, exceed all others. As a botanist's tree, perhaps Q. Cérris is the most interesting European species, from the very great variety of forms which its leaves assume; and from their being, in some varieties, persistent in a dried or withered state; and in others, remaining on green throughout the winter. The dwarf oaks, both of Europe and America, are curious miniature trees or shrubs. Q. I'lex has many interesting associations connected with it; and Q. Æ'gilops, from its remarkable foliage and calycanthus-like cups, is a most singular and beautiful tree. For the purposes of naval or civil construction and tanning, no species is at all to be compared with those belonging to the group Ròbur.
Comparing the forms and outlines of oaks with the forms and outlines of other trees, we shall find that they have greatly the advantage in point of character and variety. The forms of all the pine and fir tribe, more especially before they begin to decay, are monotonous; and the same may be said even of the forms of the cypress, the Lombardy poplar, and the weeping willow. If we imagine ourselves in a forest of pines, firs, Lombardy poplars, or weeping willows, it is easy to conceive the melancholy impression that the scenery would produce on us; and hence, perhaps, the suitableness of these, and other uniform regular-headed trees, for cemeteries. But let us imagine ourselves in a forest of oaks, either of one kind, or of several kinds; and how different will be the ideas that will arise in our minds, and the effect that will be produced on our spirits !. Oaks, then, not only stand alone in regard to the form of their leaves, and that of their fruit, but even, in a great measure, as to their general shape.
Soil, Situation, and Climate. The oaks, both of Europe and America, to attain their full size, require a deep loamy soil, a situation low rather than elevated and a climate not liable to late spring frosts. It is remarkable that, even in countries where the oak is indigenous, both its blossoms and young leaves are frequently injured by the frosts of spring. The oaks which flourish on the worst soils are the low-growing kinds belonging to the section Flex, and some of the American oaks, especially those belonging to the group Phéllos; and those which require the best soil are, the Q. sessiliflora, the Q. Cérris, and most of the sorts composing the American group Rubræ. In elevated situations, or in the extreme north, those species which under favourable circumstances form the most magnificent trees become, as in the case of every other tree, mere shrubs.
Propagation and Culture, Transport of Acorns, fc. The oak is propagated with difficulty by every other mode except from seed; and, generally, time will be gained when the acorns are sown where the plants are intended finally to remain. It is only, therefore, when peculiar varieties are to be continued, that the process of grafting is resorted to ; and the mode by approach is almost the only one that is certain of being attended with success. There are instances, however, of whip-grafting succeeding with some species; as, for example, with Q. Sùber, Q. Cérris, and Q. C. Lucombeàna. (See Gard. Mag., vol. xii. p. 698.) When any of the common methods of grafting is adopted, by far the best stock is Q. Cérris ; on which, also, many of the sorts may be successfully budded; a practice which, we are informed by M, Rosenthal, is general in the Vienna nurseries.
As the mode of raising oaks from the acorn is the same in all the species, we shall here, once for all, give what we consider the necessary details. The acorns need not be gathered from the tree, but may be collected from the ground immediately after they have dropped ; and, as in the case of other tree seeds, they may be either sown then, or kept till the following spring. If they are to be kept, they should be made perfectly dry in the sun, or in an airy shed, mixed with dry sand, in the proportion of three bushels of sand to one bushel of acorns, or with dry moss; and then excluded from the air and vermin, by being put into barrels or boxes, or laid up in a cellar, or buried in heaps, and covered with a sufficient thickness of earth to exclude the weather. If the acorns are to be transported from one country to another, the same mixing with dry sand or dry moss, and exclusion from the air, is adopted; but the more certain mode of retaining the vital principle in acorns is, to mix them with moist earth, or with moist live moss (Sphagnum): in either of the latter mediums, they will germinate during a long voyage; but no evil will result from this, provided they are sown immediately on their arrival. When acorns are to be sown in a nursery, the soil ought to be thoroughly prepared and rendered fine; and, after the earth is drawn off the beds, or the drills opened, the acorns may either be scattered over the beds, or along the drills, so that the nuts may be about 2 in. apart; and, to regulate this distance with greater certainty, the sand may be separated from the acorns with a sieve. In either case, the acorns, before covering, must be patted down with the back of a spade in the beds, and with the back of a wooden-headed rake in the drills. The covering, wbich ought to be. of well-broken soil, should vary in depth, according to the size of the acorn ; 14 in. being enough for those of the largest size, such as those of the groups Robur, Allbæ, &c.; and } in. for those of the smallest size, such as those of the groups I^lex, Phéllos, &c. No mode of depositing acorns in the soil can be worse than that of dropping them in holes made by a dibble. The acorn drops into the hole, and becomes wedged by its sides before it gets to the bottom; and, if the upper extremity of the acorn should be downwards instead of upwards, it can hardly be expected to grow. For this reason, the dibber should only be used in pulverised soils; and the point of the instument should be of a diameter greater than the length of the largest acorn which has to be dropped into the hole. As acorns are greedily devoured by vermin, and especially by land rats and mice, they ought to be sown in an open part of the nursery, not near hedges, ditches, or houses; and where, whether in nurseries, or in fields intended to become oak woods, much danger is apprehended from vermin, they ought not to be sown till late in March, so as to lessen the period between the depositing of the acorn and its becoming a plant.
As all oaks, when young, are remarkable for throwing down long and vigorous taproots, and producing few lateral ones, they ought to be sown where they are finally to remain, especially if the subsoil be good, and other circumstances not unfavourable; but, as this cannot always be the case, it is customary among nurserymen to transplant the oak at one or two years' growth, removing great part of the taproot; some of them, however, shorten the taproot without removing the plant, by inserting the spade obliquely in the soil, so as to cut through the roots, at from 6 in, to 8 in. beneath the surface; an operation most conveniently performed when the oaks are sown in drills; because in that case the spade can first be inserted all along one side of the drill, and then all along the other. The French nurserymen, when acorns, walnuts, and other tree seeds which send down very long taproots, are to be reared with a view to being transplanted, sometimes germinate them in moist earth, or in sawdust, placed in a temperature of 50° or 60°; and, after the radicle has been protruded two or three times the length of the acorn or nut, pinch off its extreme point before the seed is committed to the soil. This treatment, which is applicable, as we have seen in the case of the horsechestnut (see p. 466.), to most large-seeded trees, has the effect of immediately causing the taproot to throw out numerous lateral fibres; which is highly favourable for transplantation, though it is not so for the rapid growth of the tree for the first year or two afterwards. To counteract its effect in this respect, when the tree is planted where it is finally to remain, and has grown there two or three years, it ought to be cut down to the ground; after which it will throw up vigorous shoots, and send down perpendicular
roots; and if from the shoots one is selected to form the future tree, and the others carefully rubbed off, the tree will advance at as rapid a rate as if it had been sown where it was intended finally to remain; and, in cases where the subsoil is bad, much more so.
In the future culture of the oak, the trees generally require side pruning when the object is a straight clean trunk. As most of the species grow erect, the hardier deciduous kinds are well adapted for hedgerows; but, as many of the American kinds are comparatively tender, they are most advantageously cultivated in masses. The group I'lex forms excellent evergreen hedges, and most of the species belonging to it endure the sea breeze. The Nepal species, as far as they have hitherto been introduced, require, even in the climate of London, the protection of a wall.
Accidents, Diseases, Insects, parasitic Plants, fc. None of the oaks are so liable to have their branches broken by high winds as most other large trees; but, on the other hand, they are said to be more frequently struck by lightning than other broad-leaved trees of the same size, or than needleleaved trees of any height. The oak is subject to few diseases, notwithstanding the many kinds of insects that live upon its leaves. As the greater part of our knowledge respecting the insects which feed on the oak relates to those which infest the species comprising the group Ròbur, and those which produce the galls of commerce and the scarlet grain, we shall defer what we have to say on this subject till we come to treat of the species alluded to. The fungi and lichens which live on the oak will be found noticed under the group Robur; and others which are common to trees generally will be treated of in a separate chapter, in Part IV. of this work. Fortunately, though the insects infesting the oak often destroy, injure, or disfigure the leaves, yet there are but very few kinds which attack the solid wood till it is in of decay, in which respect the oak differs widely from the elm, which, as we have already seen (p. 1387.), is liable to have its wood destroyed by the Scólytus at every period of its existence.
Study of the Šp Till the oaks of America began to attract the notice of botanists, the European species occasioned comparatively little difficulty. The American sorts, however, vary so exceedingly in their leaves at different seasons of the year, in different stages of their growth, and in different localities, that it is next to impossible to fix on a specific character, taken from them, which shall remain constant. The descriptions of the American oaks which have been published are, consequently, of very little use, without figures; and even the figures differ exceedingly in different authors : for example, in the works of the younger and elder Michaux, in Abbott's Insects of Georgia, in Catesby's Carolina, and in Audubon's Birds of America; not to speak of the figures in the Nouveau Du Hamel, and other works published on American oaks by botanists who have not been in America.
All the species of oaks hitherto described by botanists have been arranged in sections founded on a single character taken from the leaves. Willdenow, for example, has arranged them in the five following sections : such as, 1. Leaves entire ; 2. Leaves toothed; 3. Leaves lobed ; 4. Leaves sinuate, with the lobes mucronate; and, 5. Leaves sinuate, but the lobes without any
This arrangement, which has been followed by Smith, and in the Nouveau Du Hamel and other works, has, like all others of the kind, the disadvantage of bringing together species which are not allied in perhaps any other particular than that which characterises the section. Thus, in all Willdenow's sections, evergreens are indiscriminately mixed with deciduous kinds ; large-leaved, rapid-growing, lofty trees, with small, slow-growing, bushy trees; and so on. We do not mean to say that this arrangement is without its use; but we think it decidedly inferior to one in which the species are thrown into groups according to a totality of characters. Such a classification cannot, in the case of this genus, in our opinion at least, be effected satisfactorily either from dried specimens or drawings ; and, therefore, till the whole of the species have been seen in a growing state by one botanist, it cannot be rendered complete. After duly considering all the materials of which we have been able to avail ourselves, we have thought it best to throw into groups those species which we have seen in a living state in the neighbourhood of London or elsewhere; and to place the remainder in Appendixes, according to their native countries. In characterising our groups, we have followed Scopoli and Michaux, in paying particular attention to the fructification and the bark, as well as to the leaves; and, with regard to the latter, noticing not only their form, but, in the deciduous kinds, the colours which they assume in autumn before dropping off, because we find this a very constant character. Our groups are the following:
A. Leaves deciduous.
a. Natives of Europe, s i. Ro'rur. British Oaks. Leaves lobed and sinuated; dying off of a
yellowish or russet brown. Bark rough. Buds ovate. Fructification annual. Cups imbricate. ii. *CE'RRIS. Turkey Oaks. Leaves lobed and sinuated, or dentated; in some varieties subevergreen; always dying off a dirty white. Bark rough. Buds furnished with linear stipules. Fructification biennial. Cups echinate, ramentaceous, or scaly-squarrose.
b. Natives of North America. s iii. A’LBÆ. White Oaks. Leaves lobed and sinuated; dying off more or
less shaded with a violet colour. Bark white, and scaling off in thin laminæ. Fructification annual. Cup imbricate, or echinate. Nut oblong, generally
large. ☆ iv. PRI'NUs. Chestnut Oaks. Leaves dentate ; dying off of a dirty white,
or of a rich yellowish orange. Bark white, rough, and scaling off. Fructifi
cation annual. Cup imbricate. Nut ovate, rather large. ♡ v. Ru'BRÆ. Red Oaks. Leaves lobed, sinuated, and deeply cut, mucro
nated ; dying off of a deep red, scarlet, or purple. Bark blackish ; smooth or furrowed, but never scaly. Fructification biennial. Nut ovate, and with a
persistent style. Cup imbricate, large in proportion to the nut. s vi. Ni'GRÆ. Black Oaks. Leaves obtusely and very slightly lobed ; with
mucros, which generally drop off when the leaves have attained their full size; leaves dying off of a blackish green, or very dark purplish red, and in America frequently persistent. Bark quite black, smooth, or furrowed; but never scaly. Fructification biennial. Cup imbricate. Nut with a persistent style, and sometimes marked with dark lines. vii. PHEʻLLOS. Willow Oaks. Leaves quite entire ; dying off without much change of colour; but in America sometimes persisting during two or three years. Young shoots straight and wand-like. Bark very smooth, black, and never cracked. Fructification biennial. Cup imbricate and shallow. Nut roundish and very small.
B. Leaves evergreen,
a. Natives of Europe. ỹ viji. I'lEx. Holm, or Holly, Oaks. Leaves ovate or oval, entire or ser
rated, with or without prickly mucros. Bark smooth and black, or rough and corky. Fructification biennial. Cup imbricate. Nut ovate, acuminate; sometimes very long in proportion to the cup.
b. Natives of North America. Q ix. Vire'ntes, Live Oaks. Leaves oblong-lanceolate; dentate and variously
cut when young, but on full-grown trees quite entire. Bark smooth, black. Fructification biennial. Cup imbricate. Nut long.
c. Natives of Nepal. x. Lana'TÆ. Woolly-leaved Oaks. Leaves oval, oblong, or lanceolate; serrated or dentate; woolly beneath.
A. Leaves deciduous.
fi. Ròbur. British Oaks. Sect. Char. Leaves lobed and serrated ; dying off of a yellowish or russet
brown. Bark rough. Buds ovate. Fructification annual. Cups imbricate. Trees from 30 ft. to above 100 ft. high. * 1. Q. PEDUNCULA'TA Willd. The common, or peduncled, British Oak. Identification. Willd. Sp. Pl., No. 65. ; Ehr. Arb., 77. ; Pl. Off., 169. Synonymes. Q. Robur Lin. Sp. Pl., 1414., Sm. Fl. Br., No. 1., Eng. Bot., t. 1342., Woody. Med. Bot.,
t. 136.; Q. R. pedunculatum Mart. Fl. Rust., t. 10.; Q. fæ'mina Roth Germ., 1., p. 408., 2. p. 2. 488., Fl. Dan., t. 1180. ; Q. racemosa N. Du Ham., 7. p. 177., Lam. Dict., 1. p. 715.; Q. cum longo pedunculo Bauh. Pin., 420.; Q. Hémeris Dalech. Hist., 4.,
Quércus Puchs Hist., 229., Matth. Valgr. 1. p. 184., Tabern. Kreuterb., 1974.; Q. navalis Burnet; Chêne blanc Secondat, p. 16. t. 3. ; Chene a Grappes, Chêne femelle, Gravelin, Fr.; Stiel Eiche, früh Eiche, Thal Eiche, Lohe Eiche, Wald Eiche, Ger. Derivation. The French and German names signify the white oak, the bunch-fruited oak, the female
oak, the stalked oak, the early oak (alluding to the production of the leaves), the valley oak, the tanning oak, and the wood oak. Engravings. Eng. Bot., t. 1342.; Woodv. Med. Bot., t. 126.; Mart. Fl Rust., t. 10.; Fl. Dan.,
t. 1180. Du Ham. Arb., 2. t. 47.; Hunt. Evel. Syl., i. in p. 69.; N. Du Ham., 7. t. 54.; Willd.
Abbild., t. 140. ; our fig. 1567.; and the plates of this tree in our last Volume. Spec. Char., fc. Leaves deciduous, oblong, smooth,
dilated upwards; sinuses rather acute; lobes obtuse. Stalks of the fruit elongated. Nut oblong. (Willd.). A tree, from 50 ft. to above 100 ft. high, with spreading tortuous branches and spray, and, when standing singly, with a head often broader than it is high. It flowers in April, and ripens its fruit in the September
Leaves downy beneath. There are plants
pubescens of Willd.
i. p. 725., N. Du Ham., vii. p. 178. t. 55., Lodd. Cat., ed. 1836 ;