Burial and Compaction of Sandy Soils to Prevent Emergence of Adult Stable Fly (Diptera: Muscidae) at the Soil Surface.

Stable fly (Stomoxys calcitrans L.) remain a significant pest affecting livestock and rural communities on the Swan Coastal Plain around Perth, Western Australia. Vegetable crop residues remaining after harvest enable stable fly development. Left untreated they can produce from several hundred to >1,000 stable fly/m2 of post-harvest residues. We studied the effect of burial and compaction of sandy soils on adult emergence of stable fly and house fly (Musca domestica L.) (Diptera: Muscidae). Adults of both fly species can move up through 50 cm of loose, dry sand, however at depths greater than 60 cm, emergence rapidly declines with <5% of adults surviving under 100 cm of soil. Burial of stable fly larvae and pupae under 15 cm of soil followed by compaction using a static weight dramatically reduced adult emergence. Moist soil compacted at ≥3 t/m2 completely prevented stable fly emergence whereas house fly emergence was not affected. One t/m2 of compaction resulted in <5% emergence of stable fly buried as pupae. Soil that was easily compactible (i.e., high silt, fine sand and clay content) reduced stable fly emergence more than soil with more coarse sand and low clay content. This study demonstrates the potential for a novel and chemical-free option for controlling stable fly development from vegetable crop post-harvest residue. Field trials are needed to confirm that burial and compaction of vegetable post-harvest residues using agricultural machinery can dramatically reduce the subsequent emergence of adult stable fly on a large scale.

Amending Poultry Broiler Litter to Prevent the Development of Stable Fly, Stomoxys calcitrans (Diptera: Muscidae) and Other Nuisance Flies.

Spent poultry litter use as a fertilizer in horticulture supports stable fly Stomoxys calcitrans (L.) (Diptera: Muscidae) development. Stable fly continues to have an economic impact on livestock production and rural lifestyle in south-western Australia. The use of raw poultry manure is banned in 12 Shires surrounding Perth. The loss of market options for West Australian broiler growers has caused economic hardship. Hence, this study examined a range of chemical and biological amendments to spent poultry broiler litter in preventing stable fly and nuisance fly development. These included alkalizers (i.e., lime sand, quicklime, soda ash, and shell grit), acidifiers (aluminum sulfate, sodium bisulfate), gypsum, zeolite, spongolite, calcium cyanamide, and two fungal agents. The treated litters were placed under irrigation in horticulture with amendments added prior to them being exposed in the field as replicate 1-liter pads. In total, 19,559 stable flies developed from the spent litters exposed over five field experiments (88.7% of all flies recovered). House flies (Musca domestica L. (Diptera: Muscidae); 2,067 or 9.4%), false stable flies (Muscina stabulans Fallén (Diptera: Muscidae); 414 or 1.9%), and two sarcophagids (flesh fly) also developed from the litter. Borax completely prevented any fly development from the litter. Calcium cyanamide (1-2.5% v/v) and sodium bisulfate (10%) reduced stable fly numbers by as much as 99-100% when added to litter. Alkalizers, zeolite, spongolite, and entomopathogenic fungi had no significant impact on stable fly development. The addition of either calcium cyanamide or sodium bisulfate to raw litter can boost the fertilizer value of the litter while preventing stable fly development.