Pinus Laricio (Corsican Pine, or Black Pine). As indifferent to exposure as P. austriaca, P. montana (dwarf), and P. sylvestris (Scotch Fir), a well-known native, which often crowns high hill-tops.

Populus alba (Abele), P. fastigiata (Lombardy Poplar), P. deltoidea (Canadian Poplar), P. nigra (Black Poplar), and P. tremula (Aspen).

In low-lying districts all these Poplars are of rapid growth, but in exposed places they make much slower progress. Even then they grow quicker than most shelter plants, and are valuable for making an effective display more quickly than some of the more permanent subjects. These can all be readily cut back within reasonable limits if desired.

Quercus Robur (Oak).

Robinia Pseudacacia. The false Acacia is one of the best town trees we have; indeed, it does well almost everywhere.

Salix alba (White Willow). This will pa.s.s unscathed through fierce storms. In fairly dry spots the rate of progress is much slower than in moister soil, but, as a set-off, the silvery hue of the foliage is more p.r.o.nounced.

Ulmus (Elm). The best of the Elms for this purpose is the Wych Elm, and one known as the Wheatley is also good.

[Ill.u.s.tration: _VARIETY TENUIFOLIA OF CORSICAN PINE (Pinus Laricio)._]

SHRUBS

Atriplex Halimus (Sea Purslane). A silvery-leaved, free-growing shrub, indifferent to soil or situation.

Berberis (the Barberry). The best of these are the strong-growing Berberis aristata, and the common Berberis vulgaris, with its several varieties.

Colutea arborescens (Bladder Senna). The golden flowers in early summer and the large inflated seed-pods in autumn are both attractive.

Cotoneaster buxifolia, Nummularia, and Simonsii. These are all pretty berry-bearing shrubs.

Cytisus albus (White Broom), Cytisus scoparius (Yellow Broom), and its varieties.

Deutzia crenata flore-pleno. A handsome flowering shrub and the most robust of its cla.s.s.

Euonymus europaeus (Spindle tree). The fruits of this are very ornamental in the autumn.

Halimodendron argenteum (Siberian Salt Bush). A pretty rambling shrub, with silvery leaves.

Juniperus communis and J. Sabina (Savin). The fact that these Junipers are evergreen is a point in their favour.

Ligustrum ovalifolium, ovalifolium elegantissimum, and vulgare. These Privets are well known for planting where the conditions are none too favourable.

Lycium chinense (Box Thorn). A rambling shrub holding its own almost anywhere.

[Ill.u.s.tration: _AVENUE OF ABIES n.o.bILIS GLAUCA AT MADRESFIELD COURT._

(_The avenue is quarter-mile long, planted in 1868; average height of trees 60 feet and 45 feet apart._)]

Osmanthus of sorts. Holly-like evergreen shrubs.

Philadelphus coronarius (Mock Orange). Though less showy than some others, this is decidedly the hardiest.

Phillyraea decora (vilmoriniana). A valuable evergreen with deep-green, leathery leaves.

Pinus (Mountain Pine). This member of the Fir family is but a shrub in stature. It is at home in bleak spots.

Potentilla fruticosa (Shrubby Cinquefoil). A low shrub that produces its golden blossoms in July and August.

Prunus Laurocerasus rotundifolia. One of the hardiest forms of the Common Laurel.

Rosa canina (Dog Rose) and Rosa rubiginosa (Sweetbriar) are general favourites.

Rubus (Bramble). The cut-leaved, the double white, and double pink are ornamental.

Spartium junceum (Spanish Broom). However bleak, this will produce its comparatively large pea-shaped blossoms throughout the summer.

Staphylea pinnata (Bladder Nut). The bladder-like seed-capsules are striking in the autumn.

Symphoricarpus racemosus (s...o...b..rry). Grows anywhere, and produces its large white berries in great profusion.

Ulex europaea (Common Furze). The double form of this is remarkably showy.

Viburnum Opulus (Guelder Rose). A pretty native shrub.

[Ill.u.s.tration: _CEDRUS ATLANTICA GLAUCA AVENUE AT MADRESFIELD COURT._

(_Avenue is about quarter-mile long, planted in 1866. All seedling trees, hence some difference in growth and colour._)]

CHAPTER XVI

CONIFERS (INCLUDING PINES) IN ORNAMENTAL PLANTING

Those who take a serious interest in their gardens and other planted grounds are so rapidly acquiring a better comprehension of the art in its wider aspects, and are so willingly receptive of further suggestion, that we emphasise a lesson that we have often tried to teach, namely, the importance of planting in large groups of one thing at a time, and of a right choice.

There is no more common mistake made than that of planting just the wrong things in the wrong places. Thus we see plantations of Spruce on dry, sandy hill-tops, from whence the poor trees must look with longing eyes to their true home in the moist, alluvial soil of the valley-bottom below. In mixed plantations we see Conifers from many climes and all alt.i.tudes, all expected to do equally well in perhaps one small s.p.a.ce of garden ground. If in a projected plantation there is s.p.a.ce for only fifty trees, how much better it would be first to ascertain which out of a few kinds would be best suited to the soil and general conditions of the place, and then out of this selection to choose the one that best fits the planter's own liking and will be most in harmony with the further planting scheme that he has in view. In this way he will obtain that unity of effect that alone can make a garden or piece of planted ground pictorial and restful, and enable to serve as a becoming setting to the brightly-coloured flowering plants that will then show their proper value as jewels of the garden.

[Ill.u.s.tration: _LIBOCEDRUS DECURRENS AT FROGMORE (about 65 feet high)._]

In this restrained and sober use of trees, and especially of Conifers, it is well to plant them of several ages, the youngest to the outer edges of the groups. If there is plenty of s.p.a.ce it will be all the better to plant the trees in hundreds rather than in fifties, or in any case in s.p.a.ces large enough to see one whole picture of one good tree at a time. Where such a planting was wisely made from forty to sixty years ago how fine the effect is to-day, as in the case of the grand growth of Douglas Firs at Murthly. No one seeing so fine an example of the use of one tree at a time could wish that the plantation had been mixed, or could be otherwise than deeply impressed with the desirability of the plan.

One such large group can always be made to merge into another by intergrouping at the edges, beginning by an isolated tree of group B in the further portion of group A, then a group of two or three of B, until the process is reversed and the group is all of B, with single ones of A giving place to all B. There is no reason why the same principle should not be used with two or three kinds of combined grouping, but then it should be of trees harmonious among themselves, as of Spruce and Silver Fir, or of such things as represent the natural mixture of indigenous growth. Thus the Yew, Box, Viburnum, Dogwood, Privet, and Thorn of a wild chalky waste might be taken as a guide to planting some of these with nearly allied foreign kinds. But the important thing in all such planting is to have the satisfactory restfulness and beauty of harmony that can only be obtained by the right and limited choice of material.

Although a few Conifers are deciduous, such as the Maidenhair tree (_Ginkgo biloba_), _Taxodium distichum_, the Golden Larch (_Pseudolarix Kaempferi_), and the true Larches, the great bulk of the family consists of evergreens. It is to the Coniferae, indeed, that belong the only hardy evergreen trees which in stature and size rival the large deciduous trees of cool temperate lat.i.tudes. Although our only native Conifers are the Yew, the Scotch Pine, and the Juniper, there is a sufficient variety of soil and climate within the limits of the British Isles to provide suitable conditions for nearly the whole of the family. It is only a few sub-tropical species that cannot be accommodated. This does not imply that the whole of the hardy Conifers can be grown satisfactorily in any one place. In even the best Conifer localities there are some species that will not reach perfection, and in the general run of gardens there is a considerable proportion of species about which the same must be said. This fact, however, has often been overlooked.

The extreme popularity of Conifers, which was at its height from forty to fifty years ago, undoubtedly led to the enriching of the parks and gardens of this country with what are now, in many instances, magnificent specimens. To realise how great that enrichment was, one has only to mention such places as Dropmore, Murthly Castle, Ochtertyre. But Conifer planting, from both artistic and merely cultural points of view, was overdone. Conifers began to fill an undue proportion of s.p.a.ce in gardens, and displaced to a large extent the beautiful flower-bearing deciduous vegetation whose seasonable variations give such charm and interest. With all their symmetry and richness of hue, the popular species of Abies and Picea often have a heavy, even sombre, aspect.

Heavy ma.s.ses of Pine, Spruce, and Fir can never give that changing aspect in the landscape that comes with deciduous vegetation. The tender tints of spring, the flowers, the gold and purple of autumn, it is to these that the seasons of our northern lat.i.tudes owe their greatest delights.

Perhaps the worst of all the uses to which Conifers have been put is that of forming long avenues across parks. It is difficult to understand the frame of mind that would prefer rows of _Araucaria_, _Abies n.o.bilis_, or other similar things--however well grown and pyramidal they might be--to a n.o.ble vista of Chestnut, Oak, or Lime, with its canopy of branch and foliage overhead. Conifers can, however, be used effectively for forming short avenues within the garden itself, especially in the more trimly-kept parts.