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If it be thoroughly understood that trees of different species do not perform 

 their various functions connected with rest and growth simultaneously, and that our 

 seasons are exceedingly irregular compared with those of Europe, on the recorded 

 experience of which many of us rely, perhaps too much, we shall have learned a good 

 deal. And let it be further noted that we have a good deal of pioneer investigation 

 to do yet — in other words, that when a man asks us the best time to ringbark a certain 

 tree, we have frequently no precedent to offer him. Because Stringybark was success- 

 fully ringbarked at one place in September, 1911, it does not follow that Box may be 

 successfully ringbarked at the same or any other place in September, 1921. If we could 

 prepare a column of statistics in this way, just as we record physical constants, what a 

 boon it would be ! No, we must approach this subject, the importance of which is still 

 of such magnitude to Australians that outsiders can scarcely understand, in another way. 

 We must consider the tree as a hving organism, and give some attention to the physiology 

 of tree-growth. 



The first thing is to ascertain when the sap is " up " (to use a rather loose phrase, 

 the meaning of which is. however, well understood in practice), evidence of which is 

 shown by the facility with which the bark strips, and also by the formation of the leaves, 

 to be noted at a distance by their greater greenness or freshness of colour, often of a 

 shade of purple. (In Australia we have, of course, mainly to deal with non-deciduous 

 trees, but, nevertheless, it is usually an easy matter for a careful observer to note the 

 extent to which the flush or formation of a new growth of leaves has extended, or whether 

 the tree is at rest.) For an account of the physiology of the processes connected with 

 sap-movement, I must refer to the text-books. But I may remind my readers that 

 starch is contained in the sap of trees, or a substance from which starch is obtained. 

 This starch is separated from the sap and is stored up, during the period of active growth, 

 in the wood, and especially in the rootwood, ready for the formation of buds (usually 

 leaf buds), which buds usually burst in the spring, but the season of bursting forth is 

 exceedingly variable with various trees, as I have already hinted. Every forester, 

 every man concerned in the procuring of timber, and every pastoralist, should make 

 and preserve records of the periods of " flushes " of leaves on each of the various kinds 

 of trees in his own district. Considerable success has attended the ringbarking of trees 

 as they come into flower. The trees are very vulnerable then. 



Now, many trees, if the bark be injured or ringbarked, have the power of 

 developing the latent buds (these buds may develop from mere exuberance of sap, 

 without the tree having been visibly injured) which exist under the bark, which buds 

 are developed by means of the store of starchy matter which we have already referred 

 to as existing in the rootwood (and in the stump). In other words, we have " suckers " — 

 those curses of the forester and pastoralist. 



So here, as pointed out by Farrer and others many years ago, we have, I think 

 the key to the problem of ringbarking. If a tree is to be rung, see that the work is done 

 properly — right through the cambium layer all round. Then see that it is cut at a 

 period when the particular kind of tree operated upon has little or no starch or bud- 

 sustaining material left in its roots. In other words, see that it is cut off from its base 



