Insect Pests of Roses

Insects of Roses Prof. Robert L. Morris Area Horticulturist, UNCE, Emeritus Adapted from University of California IPM Project http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7466.html

COMMON INSECT AND MITE PESTS The key to control: • careful selection of varieties • good attention to appropriate cultural practices • occasional handpicking or using soap and water to spray away pests • control weeds • keep an eye out for rising populations of natural enemies and encourage them

Aphids

Natural Pest Control

Chemicals 1.

2.

3.

4.

5.

Water Soap and water ½ and ½ solution of Listerine and water Neem Imidacloprid (Bayer)

Insects and Mites That Cause Leaves to Stipple or Yellow • Spider mites • Rose Leafhopper

Spider Mites - leaf scorch, leaf bronzing, dusty

Non chemical Control • Insect screens • Yellow sticky traps

Rose Leafhopper - stippling

Insects That Distort or Discolor Blossoms • Western Flower Thrips

Insects That May Chew Blossoms and/or Leaves • • • • • • •

Leafcutter bees Caterpillars Earwigs Rose curculio Fuller rose beetle Hoplia beetle Rose slug

Leafcutter Bees – cuts circles in leaves and petals

Caterpillars – feed on rose leaves and may tie leaves

Rose Curculio – punches holes in flowers and buds

Fuller Rose Beetle – chews flowers and leaf edges

Hoplia (June) Beetle – chews holes in flower petals

Rose Slug – skeletonize leaf surface and holes in leaves

Insects That Cause Canes to Die Back

• Borers • Scale insects • Raspberry horntail

Flatheaded and Cane Borers cane dieback

Borer Control • Cane borer: Seal the end of the cane with Elmer’s glue

• Flatheaded borer: Prevent stress and sunburn on woody tissue

Scale Insects – stunting and dieback

Raspberry Horntail – tips of canes wilt and die

Rose Midge tip dieback and regrowth

COMMON NATURAL ENEMIES OF INSECT AND MITE PESTS IN ROSES • Aphid parasites - aphids • Minute pirate bug – mites, scales and thrips • Green lacewing –aphids and other soft bodied insects • Ladybird beetle - aphids • Soldier beetle - aphids • Syrphid fly – hover flies, aphids • Predacious mites - mites • Spiders - omnivorous

Aphid Parasites

Minute Pirate Bug

Green Lacewing

Ladybird Beetle

Soldier Beetles

Syrphid Flies

Predacious Mites

Spiders

Non Chemical Control • • • • • •

Hand picking Soap and water ½ Listerine + ½ water Pruning Water sprays Improved nutrition and water management • Mulch • Light • Air movement

Soft Pesticides • Bt (Bacillus thuringiensis) Dipel, Thuricide – caterpillars

• • • • • •

Horticultural oils (aphids, scales, mites) Neem (insecticide, fungicide) Spinosad (caterpillars, thrips, leafhoppers) Insecticidal soaps (general) Diatomaceous earth (rose slugs) Pyrethroids

Hard Pesticides • • • • • • • • • •

Orthene Di-Syston Malathion Methoxychlor Sevin Mavrik Talstar Merit Floramite Hexygon

QUESTIONS?