eighbourhood of London
Garrya elliptica is quite hardy in ordinarily sheltered positions, but
does not flower so freely as against a south wall. As it is of
Californian origin this is not surprising. This shrub resents
disturbance at the root, and in transplanting great care is necessary.

There are other species of Garrya in cultivation, but they are more
suitable to the south-western counties than to the average climate of
Britain.

To the catkin-bearing family belong several other well-known trees, such
as the Birches, Hornbeams, and Sweet Chestnut; but flowering later in
the year their beauty is apt to pass without notice in the great flush
of bloom that comes in with April. The beautifully fragrant Sweet Gale
must not be passed without mention. Its reddish brown catkins are formed
before autumn, and expand on the still leafless twigs in spring.

CHAPTER X

AUTUMN COLOURS

There is a mystery about the autumn colouring of the foliage of our many
beautiful hardy trees and shrubs in this country, and we have never yet
ascertained with any degree of exactness the conditions that produce the
richest and brightest tints. Probably the conditions most favourable
generally are provided by a good growing season--that is, a warm, moist
summer--followed by a dry, sunny autumn. But it frequently happens after
what one would regard as favourable seasons, that species which are
usually quite trustworthy in this matter fail to colour well. Probably
one set of conditions does not suit all trees and shrubs in this
respect. To produce the colouration of the leaf just before it falls
certain subtle chemical changes in its composition take place. And to
bring about these changes certain conditions in regard to sunlight,
temperature, and moisture are necessary. But in a climate such as that
of Britain, where the seasons are never alike two years together, we can
never hope to obtain the same regularity of autumnal colouring that
characterises the vegetation, for instance, of the Eastern United
States. Still, when all is said, we possess in our gardens a large
number of trees and shrubs and climbers that are delightful in their
autumnal livery of crimson, purple, scarlet, or gold. It is curious that
every season we may notice species not usually conspicuous for their
autumn tints beautifully coloured.

An over-vigorous, sappy growth, often the result of a wet, warm autumn
or too rich a soil, is certainly detrimental to autu