The ecdyson and juvenile hormone analogues show a clear difference in their effect on the house borer, Hylotrupes bajulus. In the tested dosages, the ecdyson analogues have only a slight ovicidal effect but a very clear effect on old larvae. With a dosage of 1250 mg/m², Halofenozid achieved 100% mortality after 27 weeks and Tebufenozid after 40 weeks. The two juvenile hormone analogues, Fenoxycarb and Pyriproxyfen, behave differently. They show a clearly recognisable to high ovicidal effect if the treated wood surface has not been aged, however, their eradicant effect is not anywhere near sufficient. In the case of Fenoxycarb at a dosage of 1250 mg/m², 100% mortality was only achieved after 94 weeks. Pyriproxyfen in the same dosage of 1250 mg/m² took 124 weeks to achieve 96% mortality. Fenoxycarb and Pyriproxyfen did not prove to be very weather resistant in the aging experiments. This means that treated wood in hazard class 3 must always be protected against the influence of weather with a top coat. Two months of outdoor or adequate artificial weathering showed that without a top coat the concentration of the active substance would have to be increased by at least two to three powers of ten to achieve sufficient biological effect on eggs and egg larvae required by EN 399.1 (field testing).

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