Larval Stage
Source Reduction:
The most effective mosquito control effort is directed toward the source: standing water where larval stages of the mosquito are found. Mosquitoes are extremely vulnerable during the larval stages because of their relatively dense concentrations and the limited protection shallow breeding waters offer. Periodic treatment of all catch basins and storm drainage areas, woodland and vernal pools, freshwater swamplands and meadows, wastewater treatment and settling ponds, ditches, and other man-made or natural depressions and containers will significantly reduce mosquito breeding in suitable habitats. Areas identified as supporting breeding mosquitoes are either targeted for source reduction through habitat disruption, when possible, or biorational larvicide treatments.
Habitat Disruption:
It is possible to prevent mosquito breeding in some normally suitable areas by creating unfavorable environmental conditions in the habitat. Methods include restoring water flow, improving drainage and introducing natural predators such as infectious spores and mosquito fish. AHS will identify suitable areas and identify possible intervention methods for consideration during the season.
Biorational Larvicide Treatments:
The objective of a larviciding treatment program should be to limit the emergence and dispersal of adult mosquito populations. Regularly scheduled applications of the biochemical and microbial larvicide control agents Altosid (Methoprene) and Bti (Bacillus Thuringiensis subsp. israelensis) will eliminate most preemergent mosquito populations. This should result in dramatic reductions in airborne adult mosquito populations and maintain levels below those sufficient to experience any severe nuisance or annoyance in the treated areas without harm to non target organisms. These products are most frequently applied using conventional ground based spray equipment. Although, aerial larvicide treatments should be considered for controlling mosquito breeding over large acreage (400-500 acres) or inaccessible areas during the heavy spring flood hatches and in late summer if an arbor virus epidemic is present.
Altosid (Methoprene):
Introducing this mosquito specific growth hormone to breeding areas creates a hormonal imbalance in the mosquito which disrupts normal mosquito development preventing metamorphosis from pupae to adult. Altosid is highly effective in controlling larvae in the 2nd 3rd and 4th instar stages when sufficient hormone levels are maintained in the breeding habitat. Application frequency is determined by an analysis of the water flow rates and the amount of organic matter present. Efficacy is monitored through the use of emergence traps. This product is available in briquets, pellets and liquid to suit a variety of flood and preflood treatment applications.
Briquets:
Briquets provide effective long-term mosquito control in permanent water habitats such as catch basins and woodland pools. Standard release briquets are effective for up to 30 days and the extended residual briquets remain effective for up to 150 days under optimum conditions. Extended residual briquets are useful when higher than normal water flow rates or organic matter is present, access to breeding sites is difficult or re treatment is impractical.
Pellets:
Pellets provide up to 30 days of mosquito control in continuously wet habitats and even longer under intermittently dry conditions. They are capable of penetrating dense vegetation and can be applied by hand or granular application equipment. typical treatment areas include storm drainage areas, woodland and vernal pools, freshwater swamplands and meadows, ditches, and other man-made or natural depressions and containers.
Liquid Altosid:
Liquid applications are a cost effective method of providing approximately 7 days of mosquito control in both permanent and temporary floodwater habitats. It can be applied using standard ground sprayers, (low pressure, mist blower or ULV) or aerial larviciding equipment for large scale applications to inaccessible areas.
Bti (Bacillus Thuringiensis subsp. israelensis):
This naturally occurring microbe is an extremely effective agent used in controlling a wide species range of mosquito larvae. After Bti is introduced to the larval habitat, it migrates through the water column where it is ingested by larvae in the 2nd and 3rd instar stages. Within hours the spore reacts to alkaline enzymes present in the larval gut, stimulating production of a protein crystal. The crystal rapidly gains in size causing a critical compromise in the integrity of the larval gut wall.
Granules:
Granules provide up to 14 days of mosquito control in continuously wet habitats and even longer under intermittently dry conditions. They are capable of penetrating dense vegetation and can be applied by hand or granular application equipment. typical treatment areas include storm drainage areas, woodland and vernal pools, freshwater swamplands and meadows, ditches, and other man-made or natural depressions and containers.
Liquid Bti:
Liquid applications provide fast acting, short residual mosquito control. This is an extremely cost effective method of controlling accelerated growth hatches when water temperatures are elevated in both permanent and temporary floodwater habitats during hot weather periods because it delivers rapid visible mortality within 6 hours. It can be applied using standard ground sprayers, (low pressure, mist blower or ULV) or aerial larviciding equipment for large scale applications to inaccessible areas.
Altosid and Bti combination (Duplex):
Duplex is simply a tank mix of Altosid and Bti liquid larvicides that combines the benefits of both active ingredients to produce a synergistic effect. It works against mosquitoes during all larval stages because altosid is most effective against later instars and Bti liquid is more effective against earlier instars. This also makes application timing less critical. Duplex can be applied using standard ground sprayers, (low pressure, mist blower or ULV) or aerial larviciding equipment for large scale applications to inaccessible areas.
Catch Basin Treatment Program:
Catch basins and storm drainage areas are highly productive breeding habitats for several species of mosquitoes. Treatment of all catch basin and drainage areas with Altosid XR Briquets approximately four times per season will control this source.
Adulticiding
Chemical adulticide spray applications provide immediate control of airborne adult mosquito populations. All Habitat Services uses three pyrethroid-based adulticide products, Scourge® (Resmethrin), Kicker® (Pyrenone), and Demand CS® (Lambda-cyhalothrin) to suit a variety of treatment applications. Scourge® and Kicker® are fast acting short residual products which provides quick knock down. Demand CS® is an encapsulated product that provides a significantly longer residual effect. All products, at the application rates used, are specifically targeted toward mosquitoes, gnats (noseeums) and black flies. The Demand/Kicker combination is also effective in controlling ticks. Spray applications will not harm non-target organisms, although care must be exercised to avoid spray drift over water.
Adulticide spray treatments are recommended when adult mosquito populations reach peak levels. ULV truck treatments cover all properties along roads within the Association. Mistblower spray treatments target specific harborage areas on individual properties.
ULV Spray Treatments
Application of Scourge® (Resmethrin) mosquito adulticide ULV spray treatments will provide an immediate knockdown of active mosquitoes and gnats (noseeums) over a large area. The ULV spray mist will also, penetrate vegetation and drift to control resting mosquitoes downwind. Scourge® residues will dissipate within 4 hours of direct sunlight.
Mist Blower Spray Treatments
Applications of Demand CS® (Lambda-cyhalothrin) mosquito adulticide will provide an immediate knockdown of all active mosquitoes, gnats (noseeums) and small biting flies in the treated area. Treatment of lawns, trees and vegetative borders around breeding sites, upland resting areas and specific high-use areas will create a protective barrier to control resting and migrating mosquito populations for an extended period. Demand CS® residues are microencapsulated and will remain effective on trees and vegetation for approximately 4-8 weeks depending on environmental, climate and weather conditions.
