Eradicate
Repression: Reduce the moisture of your soil to the bare minimum. Symphilids burrow deep underground when they sense drought however they will not entirely leave a food source. Dry conditions will force these root chompers deeper into the ground and away from the central root ball of your plant. Root damage will continue, but in a less dangerous location. Ironic that watering is the simplest detection and drought is the stopgap.
Predators: The symphilid is native to new zealand and little is known about their biology. With over 160 species in a vague field there is not a effective predator that will work across species. The symphilid moves too quickly for predatory mites to be effective.
Manual Removal: Alas, the recourse of manual removal against underground pests is always minimal. If you sight these pests on the surface of your soil, kill them! This is a slower moving infestation and killing a few females will aid your plant more than you think.
Spray: Symphilids require very thorough soil drenching to eradicate. Other root munching pests do not have the depth capabilities of this creature, ensure your ENTIRE medium is soaked or you will see reappearance. Symphilids are resistant to oils and soaps and their eggs are tougher than any root predator in this thread. A simultaneous application of tobacco juice and neem as a soil drench has proven effective against the symphilid. 10 cigarettes per gallon of water, soaked until the water color is between tea and coffee is sufficient. Apply this juice alongside a neem drench twice spaced 4 days apart. If symphilids appear eradicated, take a soil sample from the bottom of your container, inspect, and re-drench if necessary.
taking no credit for this, was copied off of grizzlies guide for pulverizing pests, cheers grizzly
