Pests & Diseases » Olive Lace Bug
Olive Lace Bug (Froggattia olivinia) is a serious pest of olives. Heavy infestations can cause loss of vigour,
The olive lace bug can have numerous generations per year depending on the climate. New infestations can occur regularly throughout the growing season. Eggs that have overwintered on the tree usually begin to hatch out in spring or late winter.
Management
Monitor the trees in early spring for evidence of insect infestation. Apply insecticide treatments soon after lace bug activity is first noticed. Lace bug populations can build up rapidly if left unchecked. At least two sprays are necessary 10-14 days apart to control each infestation. Keep in mind that chemical treatments do not kill the eggs. The second spray (10- 14 days after the first) targets the nymphs emerging from the eggs that were unhatched at the time of the first spray.
Spray Treatments
Low toxicity pyrethrin products are effective in controlling olive lace bug. In Australia, the pyrethrin based insecticides registered for lace bug control are PyGanic and Py-Bo. Both products are available from The Olive Centre (Tel: 07 4696 9845).
PyGanic (rate-1ml to 2 ml /L) is a natural pyrethrin and is certified for use in organic groves. Py-Bo (rate-1ml /L) is a natural pyrethrin that has been combined with a synthetic form of piperonyl butoxide (PBO) to increase the products potency. Natural pyrethrum is extracted from the flowers of Chrysanthemum spp. and has a low mammalian toxicity. Applications of Pyrethrin products must be managed carefully if beneficial insects are being used in the grove as pyrethrin's are toxic to both the beneficial insect and the pest.
Synthetic pyrethroids mimic natural pyrethrin compounds but have the advantage that they have a longer residual life and are cheaper to produce. They are very effective in controlling lace bug. Research is currently underway to obtain approval for their use in the olive industry. Synthetic pyrethroids are the active constituent in most household cans of fly spray.
A number of organophosphate insecticides have been given temporary registration for the control of lace bug on olives. These include: Dimethoate (Rogor, rate -0.75ml/L), Fenthion (Lebaycid, rate -0.75ml/L). Please check the current registration status of these pesticides with your agricultural supplier before use.
Pruning Practices
Lace bug are not difficult to kill but it is essential to obtain good spray coverage when applying chemical treatments. Before spraying badly infested trees, it is recommended that severe pruning is undertaken to reduce tree height and to open the canopy.
As well as making the management of the trees much easier, pruning will improve airflow and facilitate the penetration of spray through the trees making control of pests and diseases much more efficient.
Pruning will also help rejuvenate badly damaged trees buy encouraging new shoot development.
Once the infestation is controlled, regular monitoring of the pest is required on a fortnightly basis throughout the growing season. Usually “hot spots” will occur along the edge of the grove and/or in the vicinity of prior infestations. Hot spots start with the adult lace bug infesting a few trees. If these “hot spots” are sprayed as soon as the lace bug develops then the whole grove will not need to be sprayed.
Please note: it is a legal requirement that label instructions are followed, if olives are not listed on the label of the pesticide, it is either not registered for use on olives or an off label permit is required.
Pesticide registrations and off-label permits for olives can be viewed and downloaded from the Australian Pesticides & Veterinary Medicines Authority website: APVMA (click on search for a permit tab then enter olive under the crop section). Permits can also be checked at the AOA Website