The ex culler is correct. Spring sees high sap flow up from the roots which have stored sugars and vitamin c. Pregnant animals will look for this, even on youngish pines. Top terminal cambiym stripping on pines are usually possum and this can also coincide with pollen production which possum are also partial to. Its bad news in pine plantations because it can kill the main leader and cause the tree to grow valueless multileader stems. Ie, no straight high value sawlog. One territorial buck jacko can do a wealth of economic damage.
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