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Root elongation was measured in mature Eucalyptus pauciflora Sieber ex Sprengel subsp. pauciflora trees in a high-elevation stand, and in seedlings of E. pauciflora and E. nitens (Deane & Maiden) grown in a glasshouse. Elongation of non-mycorrhizal roots (>10 mm long) was measured at 0600 and 1800 h on several consecutive days. Root elongation of seedlings of both species in the glasshouse was greater than that of mature E. pauciflora trees in the forest. For seedlings of comparable size, roots of E. nitens elongated faster than roots of E. pauciflora. Root elongation was always greater during the night than during the day in both species, in both the glasshouse and forest environment. Both water and osmotic potentials of root tips of E. pauciflora seedlings were lower during the night than during the day. The derived turgor pressure value of root tips was greater during the night than during the day and there was no difference in turgor pressure above the yield threshold. [ABSTRACT FROM PUBLISHER]

This article describes the rates of seed removal, estimated using a baiting technique that is tested for its reliability, by the seed-eating ants in adjacent heath and woodland sites in southeastern Australia. The baiting technique consisted of monitoring the removal of seeds placed on a light covering of sand inside modified Petri dishes, which were placed on the ground after clearing the immediate few centimeters of litter. The dishes had lids and an opposing pair of entrances cut in their sides to allow access by ants, but excluded vertebrates and minimized disturbance by rain and wind. Baits were often found disturbed during preliminary trials, presumably by birds or mammals; this was overcome by covering them with 1 cm mesh wire cages. Since natural rates of seed removal cannot be measured directly, the likely reliability of results obtained from baits was determined by testing the influence of various artificial factors associated with the baiting technique.