Table 1. Common insects and mites associatted with poinsettias.

Sucking insects/bugs(Homoptera: sucking nymphal and adult forms) – suck sap from leaves, stems and roots causing wilting, and a build-up of honeydew and sooty mold on leaf surfaces:

-mealybugs (Pseudococcidae) – 56 day cycle

-citrus mealybug (Planococcus citri (Riso))

-striped mealybug (Ferrisia virgata (Cockerell)

-greenhouse whitefly (Trialeurodes vaporarium (Westwood)) – 42 day cycle

-sweet potato whitefly (Bemesia tabaci (Gennadius)) – 18-23 day cycle

-scale insects (Diaspididae) – 168 day cycle

-brown soft scale (Aspidiotus nerii Bouche) – 168 day cycle

-green peach aphid (Myzus persicae (Sulzer)) – several days generation

-root aphid (Pemphigus spp.)

Spider mites

(Acarina, Acari) – suck sap from clusters of epidermal cells causing leaves to appear stippled and produce webbing of silk associated with the infestation:

-two spotted spider mite (Tetranychus urticae Koch) – 14 day cycle

Thrips (Thysanoptera)

– rasp epidermal tissue causing “silvering” in spots or deformed leaves when leaves are attacked while in the process of expanding:

-greenhouse thrips (Heliothrips haemorrhoidalis (Bouche)) – 37 day cycle

Caterpillars (Lepidoptera)

– chew irregular holes in leaves, remove entire leaves, roll leaves up or web them together and occasionally tunnel into shoots:

-Poinsettia hornworm (Erinnyis ello (L.))

-beet armyworm (Spodoptera exigua (Hubner))

-leaf rollers

Flies (Diptera: chewing larvae or maggots)

– chew randomly through young roots:

-fungus gnats (Bradesia spp.) – 31 day cycle

-fungus fly (Scaria spp.)

Table 2. Symptoms of phytotoxicity.

• Burn– appears on the tip or margins of the leaf as necrotic (dead) area or the entire leaf surface may appear burned, or the roots can be burned.
• Chlorosis – appears as spots, tip or marginal yellowing or even entire leaf yellowing.
• Leaf distortion – appears as curling, crinkling or cupping of the leaf.
• Stunting – reduction in size of entire plant or certain parts (fruit, flowers, roots) while rest of plant appears normal.
• Abnormal growth – stimulation of excessive growth on either certain parts (aerial roots, suckering) or the entire plant.

Table 3. Symptoms of phytotoxicity.

I. Biological Control Agents

A. Predators

1. Chrysoperla carnea (common green lacewing) – for aphids, whiteflies.
2. Chrytolaemus montrouzieri (mealybug destroyer, a lady beetle) – for mealybugs.
3. Delphastus pusillus (a lady beetle) – for whiteflies.
4. Predatory mites (Phytoseiulus persimilis, Phytoseiulus longipes, Amblyseius cucumeris, Amblyseius barkeri) – for spider mites.

B. Parasites

1. Encarsia formosa ( a small wasp) – for greenhouse whiteflies (not as effective for sweetpotato whitefly).
2. Steinernema carcapsae (nematode, Guardian Nematode, Biosafe and others) – for fungus gnat (larvae).
3. Trichogramma minutum and other species (small wasps) – for caterpillar eggs.

II. Insecticidal Soaps and Oils

A. horticultural oil (SunSpray Ultra-Fine Spray Oil) – for fungus gnats, aphids, mealybugs, scale insects, whiteflies (eggs, nymphs, adults), spider mites. After several repeated applications may cause leaves to appear oily.
B. Insecticidal Soap (M-Pede) – for sphids, mealybugs, scale (crawlers), whiteflies (eggs, nymphs, adults), thrips, spider mites. Do not make more than three consecutive application. May leave residue, particularly if water has high mineral content.

III. Insect Growth Regulators

A. Chitin synthesis inhibitors

1. azadiractin (Margosan-O, Botanical Insecticide Concentrate) – for catepillars, loopers, beet army worms, mealybugs, whiteflies (nymphs and pupae), thrips.

B. Juvenile hormone mimics

1. fenoxycarb (PT 2100, Preclude) – for scale insects and whiteflies (nymphs and pupae).
2. kinoprene (Enstar 5E) = for fungus gnats, aphids, mealybugs, root mealybugs, scale insects and whiteflies (eggs, nymphs, pupa, adults).

IV. Microbial Insecticides (Bacterials)

A. Bacillus thuringiensis var. kurstaki (Javelin WG and others) – for caterpillars
B. Bacillus thuringiensis var. israelensis (Gnatrol Biologicals Larvicide, Vectobac Biological Larvicide) – for fungus gnat larvae.

V. Botanicals

A. azadirachtin (Margosan-O) (see insect growth regulators)
B. pyrethrins(Pyrenone Crop Spray Insecticide, Xclude Encapsulated Natural Pyrethrum PT 1600A) – for ants, caterpillars, flies, aphids, mealybugs, scale insects, whiteflies (nymphs and adults), thrips, spider mites. Do not apply on bracts.
C. nicotine (botanical) (Nicotine Smoke Generator) – for flies, aphids, thrips. Reported to affect whiteflies (nymphs and adults).

VI. Derivatives of Pyrethrins

A. resmethrin (Resmethrin EC 26 Insect Spray, PT 1200 Resmethrin) – for ants, caterpillars, flies, fungus gnats, aphids, mealybugs, scale insects, whiteflies (nymphs and adults), thrips and mites.
B. sumethrin (PT 1400 Sumethrin) – for ants caterpillars, aphids, mealybugs, whiteflies, spider mites.

VII. Pyrethroids

A. bifenthrin (Talstar 10 WP) – for red imported fire ants (EPA SLN No. TX-910013), armyworms, leafrollers,aphids, mealybugs, whiteflies (nymphs and adults), spider mites. May leave residue.
B. cyfluthrin (Deathlon Ornamental Insecticide, Tempo 2 Ornamental Insecticide) – for ants, armyworms, leafrollers, flies, aphids, mealybugs, scale insects (crawlers), whiteflies (nymphs and adults), thrips, clover mites.
C. fenpropathrin (Tame 2.4 EC Spray) – for armyworms, aphids, mealybugs, whitleflies (nymphs and adults), spider mites (see tank mixtures section.)
D. fluvalinate (Mavrik Aquaflow) – for caterpillars, aphids, mealybugs, whiteflies (nymphs and adults), thrips, spider mites. Also registered for dipping foliar cuttings.

VIII. Chlorinated Aryl Hydrocarbons and DDT Relatives (Diphenyl Aliphatics)

A. dienochlor (Pentac Aquaflow) – for spider mites (see tank mixture section)
B. endosulfan (Thiodan 3 EC) – for aphids, whiteflies (adults).

IX. Avermectins (Macrocyclic Lactone)

A. avermectin B1 (abemectin) (Avid 0.15 EC Miticide/Insecticide) – for spider mites. Also reported to affect whiteflies (nymphs and adults) and thrips.

X. Carbamates

A. bendiocarb (Dycarb, Ficam W 76% WP Insecticide) – for leafrollers, aphids, mealybugs, scale insects, whiteflies, thrips.
B. fenoxycarb (PT 2100 Prelude) – see insect growth regualtors
C. formetanate (Carzol SP) – for western flower thrips (EPA SLN No. TX-920019).
D. methiocarb (Mesurol 75% WP Insecticide – Molluscicide, PT 1700 Methiocarb) – for aphids, scale insects, whiteflies, mites. E. methomyl (Lannate Insecticide, Lannate L Insecticide) – for armyworms, leafrollers, aphids, thrips (EPA SLN NO. TX-910014 & 15).
F. oxamyl (Oxamyl 10% Grandular, Vydate L Insecticide/Nematicide Water Soluble Liquid) – for fungus gnats, aphids, mealybugs, scale insects, whiteflies, thrips, spider mites.

XI. Organophosphates

A. acephate (Orthene Turf, Tree and Ornamental Spray, PT 1300 Orthene) – for leafrollers, loopers, aphids, mealybugs, scale insects, whiteflies, thrips (see tank mixtures section).
B. chlorpyrifos (Dursban 50 W Insecticide) – for ants, armyworms, green fruitworms, leafrollers, aphids, mealybugs, scale insects, whiteflies, thrips, red spider mites.
C. dichlorvos (products listing poinsettia on label) – for aphids, mealybugs, whiteflies (nymphs and adults), thrips, and spider mites. May be phytotoxic.
D. naled (Dibrom 8 Emulsive) – for leafrollers, aphids, mealybugs, whiteflies (adults), spider mites. Occasionally phytotoxic.
E. sulfatepp (Plantfume 103 Smoke Generator, Dithio) – for aphids, mealybugs, soft brown scale in sects, whiteflies (nymphs and adults), thrips, red spider mites.

XII. Miscellaneous Coumpounds

A. hexakis (Vendex 4L, Vendex 50 WP) – for spider mites. Do not apply to bracts.
B. propargite (Ornamite) – for spider mites. Do not combine with spray oils, other chemical or adjuvants.

XII. Tank Mixtures

A. acephate + fenpropathrn (Orthene plus Tame) – for aphids, whiteflies.
B. kinoprene + dienchlor(Enstar plus Pentac) for whiteflies.

Note:Products listed with no mention of phytotoxic affects to pointsettia may still be phytotoxic to poinsettia under certain conditions. High rates of products used, frequency of application, addition of adjuvants, plant stress (by high or low temperatures and/or excess or lack of water), poinsettia variety and light intensity can lead to phytotoxic reactions. If you are not familiar with the effects of a product, apply the mixture to a few plants an dobserve for phytotoxic reactions for several days before spraying entire planting.