Talstar P could potentially harm earthworms and other benficials should they come in contact with it; however, a surface application would not get deep enough into the soil for this to be an issue. Keep in mind, also, that earthworms have a coating that protects them from exposure to many products that would easily kill insects.
With mosquito control you want to not only be sure that the foliage on your trees and ornamentals are taken care of by maintenance and spraying, but that any standing water no matter how small is either eliminated your treated with a larvicide so the breeding cycle in the mosquitoes can be disrupted. Talstar P is one of our most recommended products for mosquito control. It will keep down the population even if your neighbor doesn't to the yard maintenance that you do.
Talstar P is effective for fire ant control. Per the product label, "Fire Ant Mound control is optimized by combining broadcast applications that will control foraging workers and newly mated fly-in queens with mound drenches that will control existing colonies. If the soil is not moist, then it is important to irrigate before application or use a high volume application. Apply broadcast treatments at 0.5 to 1 fluid oz. per 1,000 square feet. Use enough finished volume to penetrate thatch or sod. Treat mounds by applying 1 oz of Talstar P per mound in 1 to 2 gallons water by sprinkling the mound until it is wet and treat 3 feet out around the mound. Use the higher volume for mounds larger than 12”. Treat mounds with sufficient force to break their apex and allow the insecticide solution to flow into the ant tunnels. For best results, apply in cool weather (65 - 80 F) or in the early morning or late evening hours."
Mixing too much of an insecticide like Talstar P (Talstar One) is never recommended. Over-application can make an area more repellent, causing insects to avoid it so that the product cannot do its job.
Yes, Talstar P and NyGaurd IGR can be mixed together and applied at the same time. You want to apply at a rate of 1 oz Talstar to 3 ml of NyGuard into one gallon water.
For best results, Talstar P should be applied when temperatures are between 40-85 degrees F. If your temps are higher than that during the day, apply in the early morning or evening.