Journal of the Department of Agriculture, Western Australia, Series 3 Volume 1 Number 1 January- February,1952 Article 14 1-1952 Trees of W.A. Jarrah and Karri C. A. Gardner Follow this and additional works at: https://researchlibrary.agric.wa.gov.au/journal_agriculture3 Part of the Botany Commons Recommended Citation Gardner, C. A. (1952) "Trees of W.A. Jarrah and Karri," Journal of the Department of Agriculture, Western Australia, Series 3: Vol. 1 : No. 1 , Article 14. Available at: https://researchlibrary.agric.wa.gov.au/journal_agriculture3/vol1/iss1/14 This article is brought to you for free and open access by Research Library. It has been accepted for inclusion in Journal of the Department of Agriculture, Western Australia, Series 3 by an authorized administrator of Research Library. For more information, please contact [email protected]. J >* A'% t •v "*" , '•fc^rW/** *J?J!£ ^* r*#i »«4. '.^aSf «. f ip^M* Pr^ ft. • # w &fr;- •* jft.,r.!^^« " Journall of agriculture Vol. 1 19 Jan.-Feb., 1952] JOURNALOF AGRICULTURE, W.A. 77 TREES OF WESTERN AUSTRALIA *2* C. A. GARDNER, (Government Botanist) w/l "• •' "'---^"ll1tH.^ J»M TN commencing this series, in which a large number of trees will be dealt with, •I first place must be given to the species of Eucalyptus which include, besides the gum-trees, the various shrubs and mallees which make up a considerable part of the woody flora of South-Western Australia. It is hoped that these articles may sometimes distinct, sometimes obscure, prove of interest and value, for apart and sometimes the intramarginal nerve from the trees which provide us with may be so close to the leaf-margin as our local timber, some species of to be contiguous with it. The leaf con­ Eucalyptus yield valuable tannins, sists typically of a leaf blade or lamina and a number, especially the mallees, attached to the branchlet by a special are valuable for the oil which they con­ stalk or petiole, frequently twisted, so tain in their leaves, and for their pollen that the leaf assumes a vertical pen­ and nectar which are of primary im­ dulous position; at other times the leaf portance to the apiarist. is stalkless or sessile, and in a few species two opposite leaves may be join­ DESCRIPTION ed at their bases (connate) to resemble And so, in the first place, it is as well a single leaf pierced by the branchlet. to consider just what constitutes a The position of the leaves is usually Eucalyptus. They are all woody plants alternate, i.e., on opposite sides of the —that is they are trees or shrubs—and branchlet but placed one above the all have simple entire leaves of more or other; at other times they are strictly less leathery texture. The leaf has a opposite to each other. single midrib or central nerve, and The presence of oil in the fresh leaves typically what are termed lateral nerves may be detected by holding them up to which arise and diverge from this mid­ the light, when the oil cavities will rib usually to terminate in what is term­ appear as translucent dots. In the ed an intramarginal nerve which may dried leaves this character is not usu­ be close to, or remote from the leaf- ally evident, but there may be some margin. In some tropical species there indication of oil as dark spots, or min­ are two intramarginal nerves. ute depressions on the leaf-surfaces. The lateral nerves may be more or The leaves are usually of the same less parallel, or anastomose, with one colour on both surfaces, when they are another, forming a network of nerves, said to be concolorous, or they may be !! Journal of agriculture Vol. 1 1952 78 JOURNAL OF AGRICULTURE, W.A. [Jan.-Feb. 1952 dark above and paler underneath. They These consist of a stalk or filament, and are typically smooth and without hairs at the top an anther which contains the (glabrous), or they may have a sparse pollen. The anther opens by two cells, covering of short rigid hairs. or by circular or elliptical pores; most frequently these are longitudinally Flowers. parallel to each other. Sometimes by The arrangement of the flowers is upward confluence they appear as a usually constant in any given species, single curved slit. The filament is and the terms used may be understood attached to the anther at the base of with reference to the plates accompany­ the latter, when the anther is said to ing the articles; usually the flowers are be basiftxed, or it may be attached at arranged at the top of a stalk which the back, when it is dorsiflxed, or versa­ arises from the point of junction of the tile, and moves freely on its pivot. leaf and branchlet (the leaf axil). This There is a large or small gland on the stalk is termed the peduncle. The back of the anther. flowers may each possess their own special stalk (pedicel), or may be stalk- Fruits or Seeds. less, when they are said to be sessile. After pollination and fertilisation the The pedicels, or the sessile flowers in stamens wither or fall off, and the calyx- most cases are clustered at the top of tube undergoes some modification to the peduncle; when pedicellate, the form the fruit;—popularly called the group (inflorescence) is an umbel; when "gum-nut." This contains the capsule sessile, the flowers are in a head, and which in turn contains the seeds. The termed capitate. space at the top between the place occu­ The Eucalyptus flower is a simple pied by the stamens and the edge of the structure, for there are no sepals and capsule is termed the "disc," and this petals. The lower part of the bud, varies considerably in the different which becomes the cup of the flower, species, being sometimes flat as in the and enlarges or hardens to form the Tuart, domed, as in the Bullich, or it fruit is termed the calyx-tube, and is may extend vertically down to the cap­ usually truncate or flat at the summit. sule lining the calyx-tube, as in the Occasionally the sepals are represented Karri, or the Yorrel and Morrel. The by four small teeth close to or at the seeds vary considerably both in size and summit of the calyx-tube, and these are in shape; often they are minute, but always four in number. They may be sometimes as in the Marri and the Red- seen to advantage on a number of tropi­ Flowered Gum, for example, they are cal species, and on the Tallerack of the large, and sometimes winged. southern sand-heaths between Albany In addition to the fertile seeds, and Esperance, or again on the Illyarrie usually found in the lower part of the (Eucalyptus erythrocorys). The petals capsule, there are a number of sterile are quite absent, but their place is taken seeds, differing considerably from the by a bud-cap, called the operculum, and fertile seeds and usually narrow. These this is probably derived from the hard­ form what is called the "packing" in ened and concrete petals. It is indeed the upper part of the capsule, and are this operculum that is the most char­ the first to be shed when the capsule acteristic feature of Eucalyptus, and opens its valves. from which the genus derives its name— eu = well, and kalyptos = covered. The shape of the seed-leaves—those embryonic leaves which are the first to When the bud cap falls off at anthesis expand when the seed germinates—is (flowering time) the stamens expand. of importance in respect to the relation- Journal of agriculture Vol. 1 1952 Jan.-Peb., 1952] JOURNAL OF AGRICULTURE, W.A. 79 ships of species. There are two main types: the broad cotyledons of the JARRAH Jarrah and Marri, for example, and the (Eucalyptus marginata Sm.) Y-shaped or forked cotyledons of the This tree, the principal timber tree Mallets and a large number of the in­ of Western Australia occurs in South­ land trees and mallees. western Australia, and its boundary inland is determined by the winter isohyet of 30 inches. Trees and Shrubs. It thus extends as far inland as The Eucalyptus species can be con­ Mooliabeenie, Clackline, Narrogin, veniently classified according to their thence west of the Great Southern growth form into trees and shrubs, the Railway, to extend eastwards again in latter branching at or near the base, the vicinity of Tenterden, and embrac­ and without any distinct trunk. Of the ing the Stirling Range, finally termin­ shrubby forms we recognise mallees ating near the Warriup Hills. Its and marlocks; the former with a sub­ northern limits are on Mount Peron, terranean somewhat bulbous stock cap­ near Jurien Bay. It is typically asso­ able of putting forth new stems at ciated with the ironstone soils of the intervals (as for example after bush- Darling Range in the northern portion fires) and repeating this performance of its range, and indeed, it is found indefinitely, in some cases for over a everywhere within its area of distribu­ century. Those shrubby forms which tion where ironstone is present. In do not possess a bulbous base are term­ addition it grows in the sandy soils of ed marlocks, examples being Eucalyptus the coastal plain between Gingin and macrocarpa, and many others. Some­ southwards to the Albany district. times, however, a mallee may be a mar- It is a stringybark, i.e., it has a lock, and sometimes some of the inland fibrous, stringy, longitudinally-fissured trees may become mallees under certain bark which is strong.