more carefully attended to
than in England, Alph. De Candolle[760] says that there is not a
forester who does not search for seeds from that variety which he
esteems the most valuable.

Our useful trees have seldom been exposed to any great change of
conditions; they have not been richly manured, and the English kinds
grow under their proper climate. Yet in examining extensive beds of
seedlings in nursery-gardens considerable differences may be generally
observed in them; and whilst touring in England I have been surprised
at the amount of difference in the appearance of the same species in
our hedgerows and woods. But as plants vary so much in a truly wild
state, it would be difficult for even a skilful botanist to pronounce
whether, as I believe to be the case, hedgerow trees vary more than
those growing in a primeval forest. Trees when planted by man in woods
or hedges do not grow where they would naturally be able to hold their
place against a host of competitors, and are therefore exposed to
conditions not strictly natural: even this slight change would probably
suffice to cause seedlings raised from such trees to be variable.
Whether or not our half-wild English trees, as a general rule, are more
variable than trees growing in their native forests, there can hardly
be a doubt that they have yielded a greater number of strongly-marked
and singular variations of structure.

In manner of growth, we have weeping or pendulous varieties of the
willow, ash, elm, oak, and yew, and other trees; and this weeping habit
is sometimes inherited, though in a singularly capricious manner. In
the Lombardy poplar, and in certain fastigate or pyramidal varieties of
thorns, junipers, oaks, &c., we have an opposite kind of growth. The
Hessian oak,[761] which is famous from its fastigate habit and size,
bears hardly any resemblance in general appearance to a common oak;
"its acorns are not sure to produce plants of the same habit; some,
however, turn out the same as the parent-tree." Another fastigate oak
is said to have been found wild in the Pyrenees, and this is a
surprising circumstance; it generally comes so true by seed, that De
Candolle considered it as specifically distinct.[762] The fastigate
Juniper (_J. suecica_) likewise transmits its character by seed.[763]
Dr. Falconer informs me tha