The Ombava pest is more common in Pearl Millet and Sorghum crops, but this page deals specifically with the attacks in bambara groundnut crops.
COMMON NAMESombava (Oshindonga); ombuvi (Oshikwanyama,); ombwii ( Oshimbalantu); ombaa (Oshikwambi, Oshingandjera, Oshikolonkadhi)Note: The oshiwambo word "ombava" is used for various pests attacking plants at ground level. Ombava therefore also refers to the larvae of “false wireworm” (beetles), which is not included in this manual yet. PEST STATUSOmbava is a widespread pest on cereals and sometimes attacks bambaranuts as well. It is only of importance in years in which there is a dry period shortly after the crop has germinated.Only very young plants are attacked. If the attack is severe, the entire plant appears ragged and chewed. In such case many plants will die or be set back. As soon as the rain begins again, the attack is over for that crop and the caterpillars and damage symptoms disappear. DISTRIBUTIONOmbava is widespread in all four northern regions: Omusati, Ohangwena, Oshana and Oshikoto. Ombava seems to attack crops anywhere in the area if the rainfall pattern is suitable.DESCRIPTIONThe caterpillar is 10-12 mm long and cream to pale red in colour. Young caterpillars are dark grey with black stripes while older caterpillars change to reddish with red stripes. The head is black. The caterpillar lives in a dense web at the base of young plants. The web is often covered with sand and during the day the caterpillars hide underground in tunnels. Pupation takes place in small cells made of soil.The adult ombava is a tiny moth with a wing span of 12 mm. The colour is pale yellow with darker markings at the wing tips. The moth is seldom seen because it is so small. CONTROLOmbava attacks are often reduced by heavy rain. If sufficient rain is expected soon, farmers should wait until the effect of rain can be seen before using other control methods. Some farmers do not weed or thin their crop during an attack of ombava or other pest species. They fear that the weeding will increase the attack of pests.The caterpillars stay underground
during the day and are therefore difficult to control through direct application
of chemicals.
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