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How to Manage Pests
UC Pest Management Guidelines
Cotton
Leafhoppers
Scientific Names:
Potato leafhopper: Empoasca fabae
Southern garden leafhopper: Empoasca solana
(Reviewed 1/08,
updated 1/08)
In this Guideline:
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Several species of leafhoppers may occur on cotton. The southern
garden leafhopper is most common in desert valleys, and the potato leafhopper is most common in the San
Joaquin Valley. Only these two species cause economic damage. The potato
leafhopper generally appears in cotton fields near potato fields in the Arvin-Edison area of Kern County
and near the Sierra Nevada foothills in northern Kern, Tulare, and Fresno counties. Outbreaks of the southern
garden leafhopper are most common near sugarbeet fields in the Imperial Valley.
Adults are pale green, wedge shaped, 0.12 inch (3 mm) long, with inconspicuous white spots on the head and
pronotum. Adults fly or jump when disturbed. Nymphs and adults readily run backwards, sideways, or forwards.
Adults and nymphs suck sap from veins on the undersides of mature leaves, mostly on the lower
half of the plant. The midrib veins become roughened. Affected leaves may
become distorted, leathery, and develop yellow or red blotches. Though rare, severe infestation may cause plants
to shed squares and small bolls. Larger bolls may turn soft and spongy, and fail to mature. Other species cause
leaf stippling.
Natural enemies usually keep leafhoppers from building up large populations in cotton. However,
if large numbers migrate to cotton from other hosts, treatment may be needed if extensive symptoms appear.
Monitoring and Treatment Decisions
There is no treatment threshold for leafhoppers. Before applying an insecticide, check for swollen, lumpy main
veins on a sample of injured leaves to make sure the field symptoms are actually caused by leafhoppers.
| Common Name |
Amount/Acre** |
R.E.I.+ |
P.H.I.+ |
| (trade name) |
|
(hours) |
(days) |
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| The following materials
are listed in order of usefulness in an IPM program,
taking into account efficacy, selectivity, persistence,
and impact on honey bees. When choosing a pesticide, also consider
information relating to environmental impact. Not all registered pesticides are listed. Always read label of product being used. |
| |
| A. |
ALDICARB* |
| |
(Temik) 15G |
10–14 lb |
48 |
90 |
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SELECTIVITY: High |
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PERSISTENCE: Pest–Long; Natural Enemies–Short |
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MODE OF ACTION GROUP NUMBER1: 1A |
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COMMENTS: At layby by cultivation. Sidedress granules 8–16 inches to one side of the
plant row, 2–6 inches deep. Do not graze or feed trash to livestock. Do not make more than 1 application
at planting and 1 application after the crop emerges. Apply between March 1 and Sept. 1 only. |
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| B. |
MALATHION 8E |
Label rates |
12 |
0 |
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SELECTIVITY: Low |
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PERSISTENCE: Pest–Short; Natural Enemies–Short |
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MODE OF ACTION GROUP NUMBER1: 1B |
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COMMENTS: Ground or air application |
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| C. |
METHAMIDOPHOS* |
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(Monitor) 4 EC |
1–2 pt |
72 |
50 |
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SELECTIVITY: Moderate |
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PERSISTENCE: Pest–Short; Natural Enemies–Moderate |
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MODE OF ACTION GROUP NUMBER1: 1B |
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COMMENTS: Use 25 or more gal water/acre by ground or 5–10 gal water/acre by air. Apply
before bolls open. |
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| D. |
IMIDACLOPRID |
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(Provado, etc.) 1.6F |
3.75 fl oz |
12 |
14 |
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SELECTIVITY: High |
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PERSISTENCE: Pest–Moderate; Natural Enemies–Short |
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MODE OF ACTION GROUP NUMBER1: 4A |
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COMMENTS: A neonicotinoid. Foliar application. Do not exceed 0.31 lb a.i./acre/season. |
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| E. |
ACEPHATE |
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(Orthene) 97 |
4 oz |
24 |
21 |
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SELECTIVITY: Low |
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PERSISTENCE: Pest–Moderate; Natural Enemies–Moderate |
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MODE OF ACTION GROUP NUMBER1: 1B |
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COMMENTS: An organophosphate. Do not graze or feed trash to livestock. Apply in water at
5–10 gal spray/acre by air or 10–25 gal spray/acre by ground. May induce outbreaks of spider
mites. |
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| F. |
DINOTEFURAN |
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(Venom) 20 SG |
0.44–0.67 lb |
12 |
14 |
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(Venom) 70WG |
1–3 oz |
12 |
14 |
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SELECTIVITY: moderate/high |
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PERSISTENCE: Pest–Moderate; Natural Enemies–short |
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MODE OF ACTION GROUP NUMBER1: 4A |
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COMMENTS: A neonicotinoid. Kills lady beetles. |
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UC IPM Pest Management Guidelines: Cotton
UC ANR Publication 3444
Insects and Mites
L. D. Godfrey, Entomology, UC Davis
P. B. Goodell, UC IPM Program/ Kearney Agricultural Center, Parlier
E. T. Natwick, UC Cooperative Extension, Imperial County
D. R. Haviland, UC IPM Program, Kern County
Acknowledgment for contributions to Insects and Mites:
E. E. Grafton-Cardwell, Kearney Agricultural Center, Parlier
N. C. Toscano, Entomology, UC Riverside
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