How to Manage Pests

UC Pest Management Guidelines

DESCRIPTION OF THE PEST

Adult fiery skippers closely resemble butterflies but have a hooked knob at the end of their antennae. They have orange or orange-brown wings and are commonly seen feeding on lantana blossoms. Adult females glue hemispherical eggs singly to the underside of grass leaves. Newly hatch larvae notch leaves. As they grow, they consume entire leaves. The larva is about 1 inch long and has what appears to be an oversized black head, a narrowed "neck" followed by a dark thoracic shield, and a greenish brown body color with a granulated texture. Larvae spin silk shelters in the thatch from the third instar on, and are not readily seen unless flushed out with a drench test.

SUSCEPTIBLE SPECIES

Bermudagrass is preferred by fiery skippers, although they also feed on St. Augustinegrass, bentgrass, and occasionally other turfgrasses.

DAMAGE

Skipper larvae feed from May through September. Damage appears as a 1- or 2-inch diameter round spot from which all the grass has been eaten by a single larva. If there is a large population, then these spots will coalesce into dead patches. Usually damage appears on turfgrass planted near flower beds, where adult skippers feed.

MANAGEMENT

If skipper larvae are damaging turfgrass, dethatch the turfgrass to eliminate larval habitat. If monitoring indicates treatment is warranted, treatment choices include parasitic nematodes and Bacillus thuringiensis (Bt).

Biological Control
Larvae are attacked by parasitic braconid and ichneumonid wasps. The extensive soil or thatch contact of fiery skipper larvae may make Steinernema carpocapsae nematodes a valuable control measure, although this has not been tested. Bacillus thuringiensis subsp. kurstaki (Bt) may also be effective against fiery skipper, although more testing is needed to determine its efficacy for this purpose.

Monitoring and Treatment Decisions
Use the drench test to monitor this pest, see MONITORING AND TREATING INSECTS AND MITES. Five larvae per square yard on bentgrass greens and 15 per square yard in bermudagrass indicate treatment thresholds.

Mow the lawn and irrigate the site before applying insecticide, and do not mow or irrigate the turfgrass for at least 24 hours after treatment unless nematodes were applied, in which case apply a post-treatment irrigation. When Bt is applied, do not irrigate for 2 days after treatment.

Common name		Amount/1000 sq ft**	Ag Use R.E.I.+	NonAg Use R.E.I.+
(trade name)			(hours)	(hours)
The following materials are listed in approximate order of usefulness in an IPM program, taking into account efficacy and impact on natural enemies and the environment. Not all registered materials are listed. Not all registered pesticides are listed. Always read label of product being used.
A.	SPINOSAD
	(Conserve) SC	Label rates	4	until dry
	MODE OF ACTION GROUP NUMBER1: 5
B.	BACILLUS THURINGIENSIS ssp. KURSTAKI
	(various products)	Label rates	4	until dry
	MODE OF ACTION GROUP NUMBER1: 11.B2
	COMMENTS: Breaks down rapidly in sunlight and washes readily off leaves. Do not irrigate for 2 days after treatment.
C.	CARBARYL*
	(Sevin) 80WSP	1.5–3 oz	12	until dry
	MODE OF ACTION GROUP NUMBER1: 1A
**	Apply in 25 gal water/1000 sq ft.
*	Permit required from county agricultural commissioner for purchase or use.
1	Rotate chemicals with a different mode-of-action Group number, and do not use products with the same mode-of-action Group number more than twice per season to help prevent the development of resistance. For example, the organophosphates have a Group number of 1B; chemicals with a 1B Group number should be alternated with chemicals that have a Group number other than 1B. Mode of action Group numbers are assigned by IRAC (Insecticide Resistance Action Committee). For additional information, see their Web site at http://www.irac-online.org/.
+	Restricted entry interval (R.E.I.) is the number of hours (unless otherwise noted) from treatment until the treated area can be safely entered without protective clothing. Agricultural use applies to sod farms and commercial seed production.

PUBLICATION

UC IPM Pest Management Guidelines: Turfgrass
UC ANR Publication 3365-T
Insects and Mites
M. L. Flint, UC IPM Program, UC Davis
M. A. Harivandi, UC Cooperative Extension, Alameda County
H. K. Kaya, Nematology, UC Davis
Acknowledgment for contributions to Insect and Mites:
J. Hartin, UC Cooperative Extension, San Bernardino County
R. S. Cowles, Connecticut Agricultural Experiment Station, Windsor, CT
K. Kido, Entomology, UC Riverside
H. S. Costa, Entomology, UC Riverside
D. D. Giraud, UC Cooperative Extension, Humboldt/Del Norte counties

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