Description
Neoseiulus californicus is a very versatile mite predator, similar to Amblyseius fallacis in cycle. It tolerates a wider range of temperatures and lower humidity than Phytoseiulus persimilis. It is being used on a wide variety of plants including strawberries, raspberries, roses, grapes, ornamentals and vegetables. Eggs are oval and much larger than spider mite eggs. Adults are pear-shaped, light tan mites, less than 1/50 inch (0.5mm) long.
Target Pest
Spider Mite, Broad Mite, Cyclamen Mite, Russet Mite
Life Cycle
Mites are predominantly females at a 2:1 ratio. Females consume about 5 spider mite eggs per day and lay about 43 eggs during a lifetime. Neoseiulus californicus goes through five life stages: egg, larvae, protonymph, deutonymph, and adult. It completes a generation in one to two weeks, depending on temperature. Eggs hatch within 2 days and larvae begin feeding almost immediately. It takes about 5 days for Neoseiulus californicus to go from immature stages to adult.
Temperatures above 77°F will speed up reproduction and temperatures lower than 77°F will slow down reproduction. Reproduction stops at about 55°F. Reproduction continues up to 95°F and survival has been noted at 110°F. There is some evidence that Neoseiulus californicus can survive on pollen, but will not reproduce without prey.

Use in Biological Control
Neoseiulus californicus are well adapted to high temperatures (up to 90°F) as long as relative humidity is over 65%. They do best in warm, humid conditions, but will also tolerate low humidity (40-80% rH and temperatures ranging from 50°F to 105°F). They feed on pollen and spider mites and survive well even when pest populations are low if there is a pollen source.
Note: Neoseiulus californicus is an aggressive predator and will eat other beneficial predatory mites being used in the same area. Consult with Sound Horticulture before introduction if other beneficial insects are being used.
Product Information
Neoseiulus californicus are highly perishable and should be released immediately upon delivery. If storage is absolutely necessary, refrigerate at 55°F not longer than 5 days to minimize mortality.
Neoseiulus californicus is usually shipped from Sound Horticulture in a corn grit carrier. If using a concentrated amount over a large are, it may be helpful to buy additional corn grits from your local grocer and use them to extend the predator supply for application over larger areas. Gently pour predators on carrier corn grits and extension corn grits into a large jar and gently roll to mix. Gently shake predator and carrier onto the foliage of infested crops. For best results, mist the foliage prior to application so carrier will cling.
Introduction Rates
Typical release rates are 1/ft2, 20-40,000/acre, 100,000/ha. Rates are dependent upon pest levels and desired speed of control. Recommended pest/predator ration at time of release is 10:1. Avoid releases in temperatures below 45°F or above 85°F and during dry windy conditions. It is preferable to release predators in the morning while humidity is high and the soil is not hot. It is extremely important to release predators as soon as pest mites appear in the crop.
Using Chemicals
Neoseiulus californicus is susceptible to many pesticides. Field tolerance will vary with type of spray, timing, application methods, weather and crop. Avoid spraying crop one week before or after releasing predators. Some pesticides may remain toxic to predators for up to four weeks.