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174 The Trees of Great Britain and Ireland
Harper considers this variety to be a distinct species, and in support of this
opinion alleges that certain differences which he has observed in the two forms are
constant. The bark in var. imbricaria, both in cultivated and wild specimens, is
considerably thicker and more coarsely ridged than in the typical form. The
enlargement of the base of the trunk is abrupt in the former, conical in the latter.
Knees are formed more abundantly in trees of the type, and are usually slender and
acute, sometimes reaching a height of 6 feet. In var. imbricaria the knees are short
and rounded, often almost hemispherical in shape. The type is a lover of limestone,
the variety just the opposite. The distribution of the two forms is different,
dependent upon the geological nature of the soil, var. imbricaria always growing on
the Lafayette formation, which is a deposit of sandy clay, while the type always
occurs on other formations. Harper admits the occurrence of intermediate forms,
but states that they are rare. He has records of 300 to 400 stations in Georgia for
var. imbricaria, at each of which there may be from ten to several thousand trees,
while he has only seen intermediate forms about twenty times, and never more than
100 trees at one station. In the intermediate forms branchlets with distichous
leaves occur on young shoots. Harper has seen in Georgia specimens of var.
imbricaria as large as the ordinary form ; but it is generally admitted to be a smaller
tree. The two forms often grow close together, but in different situations. On the
Savilla river in Camden County, Georgia, he noticed the type growing along the
water's edge below the Lafayette formation, while a hundred yards or so away var.
imbricaria was flourishing in moist pine-barrens.
Var. imbricaria is possibly a juvenile form, analogous to Cryptomeria elegans.
The generally smaller size of the trees and the various differences noted by Harper
are probably the result of poor soil, and do not, in my opinion, entitle this form to
rank as a distinct species.
This variety was early introduced into England, as it was in cultivation,
according to Aiton, 1 at Kew in 1789. The original tree at Kew, now dead, was
living in 1886, when it was described by Sir Joseph Hooker 2 as 40 feet in height
and of remarkable habit, on account of its slender twisted stem with decurved
branches and pectinately-disposed branchlets. A small tree, 20 feet in height, is
now growing in Kew Gardens.
A tree of the Mexican kind was reported s to be growing at Penrhyn Castle,
North Wales; but Elwes saw it in 1906, and confirms the opinion I had formed
from specimens sent by Mr. Richards, that it is var. imbricaria. I t is 44 feet high
and 4 in girth, and comes into leaf later than the ordinary form growing near it.
At Pencarrow, 4 Cornwall, there is a fine specimen, which was planted about 1841
by Sir W. Molesworth. It had attained in 1899 a height of over 30 feet, with a
girth of stem of 2 feet 9^ inches at 5 feet from the ground.
1 Hortus Kewensis, iii. 372. Described as " Cupressus disticha, var. nutans; foliis remotioribus subsparsis : long-leaved
deciduous cypress." This varietal name was kept up by Ixmdon, loc. cit. 2481, who considered it to be identical with the
Taxodium sinense of cultivators of his time.
2 Bat. Mag. t . 5603 (1886), where it is described as Glyptostrobus petidnlus, Endlicher.
3 A. D. Webster, Hardy Coniferous Trees, 1 15 (1896). This tree is described in Garden, 1 887, xxxi. 480.
4 Figured in Gtud. Chron. 1 899, xxvi. 489, fig. 161.
Taxodium 175
As ordinarily seen in cultivation it is a small tree of slow growth, and is quite
distinct from the Chinese Glyptostrobus hctcrophyllus, with which it has been
occasionally confused.
3. Var. mucronafum.
Taxodium mucronatum, Tenore, Ann. Sc. Nat. ser. 3, xix. 355 (1853).
Taxodium mucronulatum, Sargent, Silva N. Am. x. 150, note 2 (1896).
Taxodium MontezuIIHZ, Decaisne, Bull. Soc. Fiot. de France, i. 71 (1854).
Taxodium mexicanum, Carrifere, Traite Conif. 1 47 (1855).
Taxodium distichum mexicanum, Gordon, Pinetum, 3 07 (1858).
This differs from the type in the foliage being more persistent, generally lasting
two years on the tree, and in the time of flowering, which is in autumn. The panicles
of male flowers are generally more elongated than those of the United States tree.
The leaves are usually shorter, lighter green in colour, and blunter at the apex.
These differences scarcely entitle this form, which occurs in Mexico, to separate
specific rank. Specimens* of the type, occurring at high elevations (1600 to 2000 feet)
in Texas, approach it in character of the foliage; and in some Florida specimens
the panicles of flowers are as large as any occurring on Mexican trees. The
cones vary greatly in size and form in trees of Taxodium, occurring both in Mexico
and the United States. Sargent, who has seen the tree in Mexico, was unable to
distinguish it, by either foliage or habit, from the type.
It is evidently a geographical form in which certain differences of foliage
have been brought about by climatic influence. One is led by a study of the
specimens from many different regions to see in Taxodium a single species very
variable in the wild state, rather than a number of distinct species.
Taxodium does not produce knees, so far as we can learn, in Mexico, where
trees generally stand upon dry ground. According to Seeman, 2 the tree is known in
Mexico as Sabino, and is diffused over the whole tableland of that country. There
are reported to be extensive forests of it at altitudes varying from 4500 to 7500
feet. Concerning, however, the character and distribution of these forests our
information is very scanty. Much more is known about the remarkable isolated
examples of very old and enormous trees, which have always attracted the attention
of travellers in Mexico. The most noted of these is the tree of Santa Maria del
Tule, about eighteen miles south-east of the city of Oaxaca, which was measured
by Baron Thielmann 3 in 1886, when its height was between 160 and 170 feet. Its
1 Specimens collected by Hillier in Keir County, Texas, are in the Kew Herbarium.
2 Botany of Voyage of H.M.S. "Herald" ( 1852-1857), p. 335.
3 Garden and Forest, 1897, p. 123 ; figured on p. 125. The tree is also depicted in Card. Chron. 1892, xii. 646, fig.
100. According to a correspondent, the girth was 139 feet in 1886 ; 25 years previously it had been 136^ feet Various and
conflicting measurements of this tree, taken by Exler, Baron von Karwinski, and Galeotti, in the early part of the nineteenth
century, are given by Zuccarini in Ray Society, Reports on Botany ( 1846), p. 19. The latest measurements of this tree I know
of are on a very fine photograph given me by the kte Hon. Charles Ellis, as follows :—
TAXODIUM DISTICHUM AT MITLA, NEAR OAXACA. Reported dimensions
Girth at 4 feet from ground, 132 feet.
11 i) o ,, ,, i, 154 »»
„ higher up . . 198 „
Height, 100 to 120 feet.
(H. J. E.)