Harbor Screening Tests of Marine Borer Inhibitors - Vi

Abstract

The Laboratory is exposing wood panels impregnated with various materials to determine their resistance to attack by marine borers. This report lists the results of harbor tests of treated panels removed from exposure between 15 August 1962 and 15 August 1963. It also lists all treated panels which have been exposed for 1 year or more and which have shown no attack or insufficient attack to warrant removal.When impregnated into wood test panels, creosote and 70-30 creosote -coal tar solution are quite effective against Martesia and teredine attack but not Limnoria attack. Copper salts, chelates, some copper complexes, and mercury salts are effective against Limnoria attack at Port Hueneme and to a lesser extent at Pearl Harbor but are ineffective against teredine and Martesia attack. Organomercury compounds are effective against Limnoria but not against Martesia or teredine borers. Tributyltin compounds are effective against Limnora and teredinc borers at Port Hueneme but have shown attack by Limnoria at Pearl Harbor. However, at Pearl Harbor they are effective against Martesia and teredine borers. Copper naphthenate (6%) and solubilized copper oxinate (containing 4% copper) are superior to creosote or creosotecoal tar in tests to date at both test sites. Phenanthrene, chloro-p-phenylphenol, and ether-soluble alkaloids of greenheart failed in a short time because of heavy Limnoria attack.Certain organic, metal-organic, ar-' .•,ganic compouncls, when combined with creosote or creosote -coal tar solutions, show promise in improving the preservative ability of these materials. Aluminum oxinate and malachite green oxalate are not effective additives. Certain treatments containing a combination of one material specifically toxic to Limnoria and another material specifically toxic to teredine borers :re also showing promise as preservative systems-Other systems of this type have experienced Limnoria and Martesia attack.The trop icalI woods antidesma pulvinumgrehat and lignum vitae are prforming well at Port Hueneme. Afambeau, genhrt ;ar inu vitae failed.at Pearl Harbor chiefly because of Martesia attack.Those treatments or woods which have not been atitacked by one or more. species during their entire period of exposure or as of 15 August 1963 are summari~zed.