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79.02.00a

Plant names

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Ferdinand von Mueller to the Gardeners' Chronicle, 1879-02 [79.02.00a]. R.W. Home, Thomas A. Darragh, A.M. Lucas, Sara Maroske, D.M. Sinkora, J.H. Voigt and Monika Wells (eds), Correspondence of Ferdinand von Mueller, <https://vmcp.rbg.vic.gov.au/id//letters/1870-9/1879/79-02-00a-final.odt>, accessed June 4, 2026

1
Letter not found. The text given here is from an editorial in the Gardeners' chronicle, 29 March 1879, p. 404 (B79.03.04). The letter is dated to early February as the latest that it could have been sent to have been included in this issue.
The letter is introduced by
AS we have felt it right occasionally to endeavour to moderate the exaggerated value attached by some to the Eucalyptus as a fever-destroying tree, it is only just that we should not ignore, and still less should not attempt to controvert, the opinion of so competent a witness as Baron von Mueller. To him, indeed, and M. Bosisto, we chiefly owe what information we have concerning these valuable trees, and to their earnest advocacy and material aid the diffusion of the tree is due. For our own parts we have never denied the value of the tree in suitable climates and situations as a rapidly growing timber tree, but we have been and still are rather sceptical as to the efficacy of the balsamic emanations to neutralise malaria and prevent fever. Where such effects have been produced—and we have no doubt whatever that such results have been witnessed—the benefit has arisen, to our thinking, chiefly from the improved drainage which the mere planting of the trees, if nothing else were done, would bring about, and by the natural purifying power which every growing tree exerts. In swamps in this country, where no Eucalyptus would live, an equally good effect would be produced by the planting of Poplars, Willows, Alders, and other fast-growing trees, quite irrespectively of any balsamic exudation. On the other hand, we do not overlook the fact that chemists have detected in the exhalations from some plants vapours which have powerful antiseptic qualities. Our doubts, however, refer rather to the infinitesimal quantities of such vapours from scattered trees. It is time, however, that we allowed Baron von Mueller to be heard for himself, as his opinions on such a matter are so much more worth than those of other people.
No one
2
Writes the Baron to us intercalated at this point.
should recommend the Eucalypts for utilitarian culture en gros in any region subject to severe frosts, nor can many species be cultivated in damp tropical lowlands, though the species from the coast-borders of tropical Australia are, in respect to their endurance of moist heat, not yet extensively tested. In an essay which I wrote some years ago for the Agricultural and Horticultural Society of India, and which was published in the Society's journal in Calcutta,
3
Probably B75.13.06
I set forth the main uses of the Eucalypts and their degree of endurance to heat and cold.
In a botanic arboretum for scientific purposes the alpine Eucalypts ought to prosper in at least the milder portions of Britain. In the Southern Alps E. coriacea and E. Gunnii ascend to a height of 5500 feet, indeed they form the best of the tall woody vegetation. They occur in spots not much below those ravines in which frozen snow lies on the shady side throughout the year, and where during the short alpine summer snowstorms occur every month, and where the spring vegetation is two or three months later than in our lowlands here.
E. polyanthemos, to which Mr. J. Smith refers as hardy at Kew, never reaches any considerable elevation on our mountains at all. E. stellulata is in the south-east of Australia almost subalpine, and E. alpina (now extinct except one tree in the Melbourne Botanic Garden, raised from seeds gathered by me in 1853) occurred only on the summit of Mount William, at an elevation of 5000 feet, where the strictly alpine
Celmisia

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and other plants which like snow for some months in the year occur. No one, I presume, ever recommended Eucalypts as timber trees to be grown in Britain, unless the hardier species perhaps in the Channel Islands. But for Cyprus, Malta, &c., these trees ought to be of an enormous and invaluable importance. We have no other hard-wooded trees which grow with a rapidity of that of the Willows and Poplars, and I do not think that even the most resinous of Pines exhale the same quantity of antiseptic oil of best Eucalyptus. Thus E. amygdalina yields 2 per cent, of oil from the fresh foliage (branchlets included), and the yield will rise, even under favourable circumstances, to 4 per cent.! This I proved as far back as 1863 in the second French Exhibition, when I placed, with the help of M. Bosisto and Mr Johnston, about thirty new kinds of volatile Australian oils, chiefly of Eucalyptus, before the technologic world.
4
International Exhibition, London, 1862? See M to J. O'Shanassy, 10 March 1862, and M to J. Hooker, 25 September 1863 (in this edition as 63-09-25c). Paris's second international exhibition was not held until 1867.
To live in a forest of
Eucalyptus amygdalina

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would restore a phthisical patient to health, if the disease had not gone beyond the first stage. Like all the terebenthine oils of Pines, so the cajuput oil of Eucalyptus and
Melaleuca

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e, and others of our
Myrtaceae

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generate binoxide of hydrogen, that potent disorganiser of putrid compounds. Hence I would be cautious in condemning Eucalyptus culture in suitable climatic zones for hygienic reasons alone.
That in tropical Australia in moist jungles paludal fevers do occur, is proved by sad experience; yet these maladies are not so severe and do not spread over such a vast area as in some other tropical regions. Moreover, the Eucalyptus in such regions, unlike those of the South, do not prevail gregariously in the fever regions of Australia, but are largely interspersed with the more ordinary trees of tropical jungles, such as
Sapindaceae

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,
Meliaceae

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,
Euphorbiaceae

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,
Verbenaceae

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,
Urticeae

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,
5
Urticaceae?
Combretaceae

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,
Rubiaceae

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, &c. Then again many of the Eucalyptus, as I have shown long ago, yield as little as one half per cent, of oil against 2 per cent, and more of all of those species (and they are many) which have the leaves copiously perforated by oil dots,
I omitted to mention that in Tasmania about half-a-dozen species of Eucalypts occur at heights of from 4000—5000 feet, thus on strictly subalpine elevations, where keen frosts prevail for several months in the year, with any amount of wet, and where the elevation just indicated would correspond to 5000 — 6000 feet in the Australian alps on account of the difference in the geographic latitude. As regards production of fuel and building timber, what trees could compete in any artificial rearings with the Eucalypts? As regards their respective hardiness, they display a degree of difference as great, if not greater, than that of the
Coniferae

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, among which, merely to quote one example — Nageia (or Podocarpus), not strictly alpine species, growing quite depressed at the verge of the glaciers (e.g.,
Nageia alpina

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), and species restricted to hot lowland jungles of equinoctial zone.
6
There had been several comments by the Gardeners chronicle of the type mentioned in their introduction. For example, they add an editorial comment to a letter on Eucalyptus globulus that they reprinted from the London Times: '[To prevent disappointment it may be well to state that the anti-malarial property is not proven. Any tree that would grow with equal rapidity would probably be equally efficacious. Eds.], 12 October 1878, p. 461; a long editorial on 26 October, p. 461, began
The silly season is not quite over yet, as the numerous letters in the daily papers on the subject of the Eucalyptus show. The planting of these Tree-Myrtles is advocated by these writers to be carried out in Cyprus, in Asia Minor, and elsewhere, and one writer in the Standard even goes so far as to recommend them to be planted on the Thames Embankment to neutralise the effects of the sewage impurities there, as also round manure factories, near outfalls, &c.!
After comments on the improbability of establishing Eucalyptus in England, the editorial concluded:
Now comes the question of the effect which these trees have in averting the evil influences of malaria, sewage-gas, and the like. The writers in the papers seem to take this beneficial result for granted, but in truth it is by no means proved. Fever is not absent from the Eucalyptus forests of Australia, and the benefits alleged to have ensued from the planting of the tree in Southern Europe may much more probably be attributed to other causes than the balsamic exhalations from the trees. We have ourselves seen something of the planting of Eucalypti in various swampy spots along the southern coasts of France and the Genoese Riviera, and we of course accept in all sincerity the statements made as to the sanitary improvement that has followed the planting of these trees in those spots. But our personal observations have convinced us that the good effects are far more likely to have been produced by drainage operations, or even by the slight improvement made in the soil by the operation of planting, than by any balsamic exudation. Again, the very rapid growth of the trees, and the proportionate exhalation of water from their leaves, must necessarily have a good effect in absorbing some of the otherwise stagnant moisture in the soil. We do not, of course, absolutely deny the beneficial effect of the balsamic emanations under certain circumstances, but we do say they are not proven, and in our opinion the exudations in question are about as useful as the bag of camphor which timid old ladies wear round their necks when fever or cholera are rife. The great value of the tree in appropriate climates and localities consists in its rapid growth, a quality not to be gainsaid.
We have written these remarks in the hope of averting the disappointment which must inevitably ensue if the advice of the ill-informed writers in the daily prints be thoughtlessly acted on.
M was evidently responding to the editorial comments of 26 October.