To investigate the termiticidal performance of cypress sapwood, cypress heartwood, and cypress sapwood treated with SOUFA solution (mainly composed of natrium polyborate) by laboratory tests.
- Samples and Methods
The specimens were 10x10x20 mm cypress sapwood and cypress heartwood produced in Tochigi Prefecture, Japan, and cypress sapwood treated with SOUFA solution on the surface, which were prepared by a housing construction company using the client’s SOUFA solution.
Sugi (Cryptomeria japonica D. D.) sapwood was used as a control.
2.2 Test method
Antimite performance tests were conducted according to JIS K 1571: 2010 “Wood preservatives – Performance criteria and test methods – 5.3 Antimite performance – 5.3.1 Laboratory tests – 22.214.171.124 For surface treatment. In other words, 150 termite workers and 15 soldier ants were placed in a plastic container in which the samples were placed and subjected to a 3-week feeding test.
However, in accordance with Annex A (Regulations) “Antiseptic and Antifungal Performance Tests for Limited Use,” the only weatherproofing operation was a volatilization operation in which the specimens were placed in a circulating dryer at a temperature of 60 ± 2 °C for 7 days.
The performance criteria were as follows
The average mass loss shall be 3% or less when the average mass loss of the untreated specimens tested at the same time is 20% or more.
Results of termite control performance tests of Japanese cypress sapwood and SOUFA-treated wood
|Test body||Amount of treatment（g/m2）||Dead insect rate(%)||Quality reduction rate(%)||Min－Max|
|Cypress sapwood||－||4||3 – 5||27||26 – 29||Mostly alive|
|Cypress heartwood||－||6||3 – 12||6||5 – 7||Mostly alive|
|SOUFA（Cypress sapwood）||※||100||100 – 100||1||1 – 1||All job ants die within a week.|
|Control wood (cedar sapwood)||－||2||1 – 3||45||42 – 52||Mostly alive|
Cypress is said to be resistant to pests.
In addition, Japanese cypress does not need to be treated for termites. In Japan.
This is determined by law. Therefore, houses in Japan are vulnerable to termites.
Many companies do not know this.
This test proved that Japanese cypress is eaten by termites.
There is a darkness in the Japanese termite industry.