OZRURAL.COM.AU


Life on the land in Australia

PESTS OF OLIVE TREES & THEIR TREATMENTS

Control of insect pests of olives

Frank Page, Department of Primary Industries and Fisheries

Two pests of olives are the most common pests of olives in Queensland:

  • black scale (which is also a common pest of citrus and gardenia) and
  • olive lace bug.
Black scale (on citrus); note the light brown crawlers and a parasitic wasp on the right(small)

Black scale (on citrus); note the light brown
crawlers and a parasitic wasp on the right.

Black scale

The predatory ladybeetle, Cryptolaemus montrouzieri, can be purchased from Bugs For Bugs, Bowen St., Mundubbera Qld (Ph.07 41654663) in spring – summer. It is often naturally present in orchards but is susceptible to toxic insecticides.

Olive lace bug

The olive lace bug is a more damaging pest as severe leaf damage can cause yellowing of leaves and leaf fall. The stressed trees may fail to bear fruit for the next 1 or 2 seasons.

No chemicals are registered specifically for this pest. The olive association is currently seeking minor use permits from the National Registration Authority for the use of other chemicals to control this important pest. Examples of pyrethroid insecticides registered for a range of other insect pests in orchards are Ausgro PY-Cap insecticide, Multicrop pyrethrum insecticide. They are fairly broad spectrum but fairly safe to operators, and not very persistent. Similarly, insecticidal soaps are available for use against some pests. Use of such insecticides may help suppress lace bug populations when applied for control of other pests.

The olive lace bug is difficult to control as it feeds and breeds on the underside of the leaf. It also multiplies prolifically. Good spray coverage is essential. It is reported to have an egg parasite but this may not be present in many locations. The repeated use of broad spectrum insecticides could result in the upsurge of secondary pests and even two spotted mites.

Other pests

At this stage new pests are being uncovered each year- one this year was a pyralid moth larva which tunnels in the fruit, as do the heliothis (Helicoverpa spp.) larvae at times.

October 7th, 2010
Topic: AGRICULTURE, FOOD DRINK, FRUIT VEG SMALL CROPS, PESTS DISEASES BACTERIA VIRUSES, PLANTS CROPS WEEDS Tags: , , , , , , ,

≡ Leave a Reply