The repellent efficacy of wood vinegar was assessed against mosquitoes under laboratory conditions at 1, 5, 10, 20, 40, 60 and 80% concentrations. The study evaluated whether wood vinegar is able to repel Culex pipiens pallens Coquillet and Aedes togoi (Theobald) from the human body and if so at what concentrations. The tests were conducted using the arm‐in‐cage method in 80 × 40 × 40 cm screened mosquito cages. The data were analyzed and compared with those of N,N‐Diethyl‐3‐methylbenzamide (deet) at 10.3% concentration. The results showed that wood vinegar provided mosquito repellence of varying degree depending on the concentration used. The observed repellence averaged from as low as 39.6% at 5.0% concentration to as high as 100% at 80% concentration against Ae. togoi. Repellence against Cx. pipiens pallens was high being 90.3% at 20% concentration, 92.2% at 40% concentration, 93.9% at 60% concentration and 100% at 80% concentration. The duration of protection time tests showed that the 40% and 60% concentrations of the wood vinegar give protection from landing of Ae. togoi for a period of up to 7 h, though the lower concentration gave lower protection after the first five hours. The results indicated that wood vinegar has mosquito repellent characteristics that tend to vary with the concentration used and the species of mosquitoes. Wood vinegar in this case was very effective in repelling Cx. pipiens pallens, even at lower concentrations while higher concentrations were required to repel Ae. togoi.

A granular formulation of 1.0% temephos (temephos G) was tested for its efficacy in mosquito larval control, residual effects and effects on non‐target microorganisms. Culex pipiens complex in septic tanks in Yangsan, Republic of Korea were used for this study. Microorganisms in the same septic tanks were used for study of non‐target organisms. After the application of temephos G at the rates of 2.0 and 5.0 mg/L to selected septic tanks, mortalities were recorded for 50 days. The effect of temephos G on non‐target organisms was studied by evaluating its effects on the bacterial populations in the treated septic tanks. It was observed that using 1.0% temephos G at a rate of 2.0 mg/L resulted in 100% mortality against Cx. pipiens larvae by the eighth day after treatment. The residual activity of temephos G was observed to continue for a time; for example 29 days after treatment, average larval mortality rates of >68.0% were observed for both concentrations. At the 50th day after treatment, the mortality rates of the Cx. pipiens larvae were observed to decrease to below 42.7% for both concentrations. Application of temephos G did not have significant effects on the bacteria populations in the septic tanks. Since temephos did not seem to have any major effects on the microorganisms, it was concluded that it is a safe and effective larvicide to use in the septic tanks at a rate of 2.0–5.0 mg/L of 1.0% temephos G.