African Black Beetle Treatment Guide
About African Black Beetles
The African black beetle (Heteronychus arator), is native to southern Africa. It has been present in Western Australia since the 1930s and occurs in the wetter coastal regions.
Newly emerged African black beetle adults are brown and fairly soft, but within hours they harden and darken to a glossy black. They are 12 to 14mm long with females being slightly larger than males. The end segments on the front legs of females are the same diameter as other legs, but are thicker on males. Adults are strong fliers, even though they feed near or just under the soil surface on plant stems and roots. The larvae are creamy white and C shaped with a brown head and may be mistaken for other beetle and insect larvae. They only have one generation per year and there are usually only adults present in winter who will then lay eggs in spring.
Why are African Black Beetles a problem?
This beetle can affect the early stages of a range of horticultural crops, and both adult and larval stages can be pests. Unlike a lot of beetles the adult of the African black beetle is the most destructive, feeding on various crops and causing a lot of horticultural damage. The African Beetle also flies which allows for greater infestation. It likes to feed on pastural land so crops grown on these lands can be susceptible to an infestation which may be pre-existing. The adult beetle will feed on stalks and stems of grape vines and fruit trees. They will also feed on vegetables such as potatoes.
Inspecting for African Black Beetles
The African beetle is attracted to light so swarming beetles around a light source could be a sign of infestation. Leaves of plants that have been attacked will turn red and fall off. Brown patches on turf and lawn are a sign of larval infestation. Adult beetles are usually found around 10 to 15 cms below turf so if you suspect activity dig a square metre of soil, if you find more than 3 adult beetles per square metre there could be a threat to crops.
Pre-Treatment Measures
The only real prevention for these beetles are chemicals as they can use the soil as cover which makes accessing them quite difficult.
African Black Beetle Treatment
To treat 100m2 of infested area, mix 24-36mL of Killzone Termiticde and Insecticide into at least 2 Litres of water and apply evenly over the infested area. Where there is heavy infestation use the higher rate to treat. Continue to inspect treated areas and reapply as required.
Tips
- To ensure optimum control, irrigate the treated area with up to 4 mm of water soon after application
- Apply after mowing to minimise loss of insecticide in clippings
- DO NOT apply to soils if excessively wet or immediately after heavy rain.
Always read product label prior to use.
