Abstract:The tortrix Choristoneura metasequoracalci Liu is a common pest of the Metasequoia glyptostroboides.It has one generation per year in Lichuan,Hubei province.After the larvae‘s being hatched,their diapause appears under the bark and the larvae spend winter there.The diapauselasts 9 or 10 months.The larvae begin to be active again in early April next year.There are five larval instars.Being mature,the larvae pupate in the tied-up leaves of their host.Now it has been found that a few larvae pupate in the rolled-up grass on the ground with the help of spin.Pupation period varies 9.5 to 15 days.Female moths oviposit on the first or second day after its emergence.Usually masses of the laid eggs are on the back of leaves.Male moths may live for 3.5—7 days,and the female moths 5—12.5 days.Each female moth lays 27—109 eggs.It will take the eggs 7.5—12 days to become hatched. It is proved to be quite effective that insecticides,such as Fenitrothion,dimethoate,Decamethrin Fevalerate and Fenthion,are sprayed to kill the larvae inside the laboratory.