Deniliquin Pastoral Times
Monitor for locusts
Local landholders are being reminded to monitor for locusts, with the Australian Plague Locust Commission predicting moderate risk for a plague.
With bumper crops on the horizon for much of the state, spring sightings should be reported immediately.
Adult plague locusts usually lay eggs in harder loamy red soils, favouring compact roads next to crops, tree lines and farm buildings, especially those built on higher ground such as ridges.
In its September bulletin, the Australian Plague Locusts Commission said there is a ‘‘moderate risk of a widespread infestation developing during spring’’ in the Riverina and Murray regions.
‘‘Surveys in early March identified a widespread adult population, with higher densities up to low-density swarm in the Hillston, Hay and Jerilderie areas,’’ the September bulletin states.
‘‘An area of fifth instar Sub-Band density was detected in the Jerilderie district and a few instances of present, numerous-density of nymphs were identified in other areas.
‘‘Surveys in mid-April identified a decrease in adult numbers in this region, with consistent scattered to numerous densities of adults but no nymphs detected.
‘‘Surveys in early May indicated further decline in adult numbers, only occasional numerous-density was detected among isolated to scattered densities of adults, with no nymphs identified.
‘‘Surveys in early June did not detect any locusts.’’
LLS officers confirmed a hatching report in Barellan in mid-March, and a small third instar band in Leeton in addition to two test drillings in the northwest of Jerilderie in early April.
The university of NSW insect monitoring radar in Hay detected a significant locust migration on the night of March 12 to 13.
As a result of those findings from earlier in the year, the Australian Plague Locust Commission is forecasting that overwintering eggs should have started hatching by late September.
It says the formation of localised bands are ‘‘possible’’.
‘‘Locust population levels could reach high density in some areas. There is a low to moderate probability of migration from and to adjacent regions in the spring,’’ the bulletin said.
If you suspect you’ve got Plague Locusts, contact your nearest Local Land Services office on 1300 795 299.