Category : Insects
Aphids (Various spp.)
Aphid on basil
Praying Mantis feeding on basil aphid
Winged adult aphid
Aphid feeding on basil
Small soft bodied insects on underside of leaves and/or stems of plant; usually green or yellow in color, but may be pink, brown, red or black depending on species and host plant; if aphid infestation is heavy it may cause leaves to yellow and/or distorted, necrotic spots on leaves and/or stunted shoots; aphids secrete a sticky, sugary substance called honeydew which encourages the growth of sooty mold on the plants.
If aphid population is limited to just a few leaves or shoots then the infestation can be pruned out to provide control; check transplants for aphids before planting; use tolerant varieties if available; reflective mulches such as silver colored plastic can deter aphids from feeding on plants; sturdy plants can be sprayed with a strong jet of water to knock aphids from leaves; insecticides are generally only required to treat aphids if the infestation is very high - plants generally tolerate low and medium level infestation; insecticidal soaps or oils such as neem or canola oil are usually the best method of control; always check the labels of the products for specific usage guidelines prior to use.
Cutworms, loopers, owlet moths, and underwings
Larave on basil leaf
Larvae feeding on basil leaf
The early stage larvae feeds on terminal clusters. Later stage larvae skeletonize the leaves. Also, they will cut the seedling stem near the base resulting in heavy loss.
Hand pick the larvae and kill them. Remove and destroy weeds and crop residue. Spray biocontrol agent (bacteria/virus) to kill insects. If infestation is severe, spray suitable insecticide.
Flea beetle on basil
Flea beetle and damage on basil leaf
Adult flea beetle on a leaf.
Flea beetle damage to leaves
Small holes or pits in leaves that give the foliage a characteristic “shothole” appearance; young plants and seedlings are particularly susceptible; plant growth may be reduced; if damage is severe the plant may be killed; the pest responsible for the damage is a small (1.5–3.0 mm) dark colored beetle which jumps when disturbed; the beetles are often shiny in appearance.
In areas where flea beetles are a problem, floating row covers may have to be used prior to the emergence of the beetles to provide a physical barrier to protect young plants; plant seeds early to allow establishment before the beetles become a problem - mature plants are less susceptible to damage; trap crops may provide a measure of control - cruciferous plants are best; application of a thick layer of mulch may help prevent beetles reaching surface; application on diamotecoeus earth or oils such as neem oil are effective control methods for organic growers; application of insecticides containing carbaryl, spinosad, bifenthrin and permethrin can provide adequate control of beetles for up to a week but will need reapplied.
Grasshopper feeding on basil leaf
Grasshopper feeding on soybean leaves
Grasshopper on basil
Initial stage grasshopper nymphs damage
Both adult and nymphs feed on foliage, buds, and tender stems. The first stage nymphs feed on leaves by forming circular holes. As the insect develops it feeds on entire foliage. Grasshoppers are very eager feeders.
Encourage birds in the field. If population is severe, spray suitable insecticide.
Japanese beetle adult
Adult Japanese beetle
Japanese beetle (Popillia japonica) larvae
Adult Japanese beetle on basil leaf
Leaves skeletonized (only veins remaining); flowers and buds damaged; plant damage may be extensive; adult insect is a metallic green-bronze beetle with tufts of white hair protruding from under wing covers on each side of the body; adult beetles are approximately 13 mm in length; larvae are cream-white grubs which develop in the soil.
If beetles were a problem in the previous year, use floating row covers to protect plants or spray kaolin clay; adult beetles can be hand picked from plants and destroyed by placing in soapy water; parasitic nematodes can be applied to soil to reduce the number of overwintering grubs; insecticidal soaps or neem oil can help reduce beetle populations.
Larvae still with in leaf mine
Thin, white, winding trails on leaves; heavy mining can result in white blotches on leaves and leaves dropping from the plant prematurely; early infestation can cause fruit yield to be reduced; adult leafminer is a small black and yellow fly which lays its eggs in the leaf; larave hatch and feed on leaf interior.
Check transplants for signs of leafminer damage prior to planting; remove plants from soil immediately after harvest; only use insecticides when leafminer damage has been identified as unnecessary spraying will also reduce populations of their natural enemies.