Integrated Protection Against Lyctid Beetle Infestations Part II. - Laboratory Dip-Diffusion Treatment of Unseasoned Banak (Virola spp.) Lumber with Boron Compounds

Abstract

A manufacturer of conventional moulding wanted a method that would prevent lyctid beetle damage to banak (Virola spp.) wood throughout the period from initial cutting in Brazil until final mouldings were in use. Because complete penetration of wood may be obtained, unseasoned banak wood was treated by dip-diffusion with disodium octaborate tetrahydrate Na₂B₈O₁₃*4H₂O as TIM-BOR®)^l or boric acid (H₃BO₃) to determine the dip time, solution temperature, and diffusion storage period that would provide optimum treatment of wood. Visual observations also were made of inhibition of mold growth during diffusion storage as a result of using < 3.0 percent concentrations of sodium pentachlorophenate (NaPCP) with TIM-BOR® and copper-8-quinolinolate (as PQ-57®) with treating solutions of boric acid. Recommendations for commercial trial treatments of freshly sawn banak and similar woods in the Brazilian Amazon are: 1. Treatment solution. In situations where most boards are 38 mm (1.5 inch) thick, a 25 to 30 percent boric acid equivalent solution of sodium borate (such as TIM-BOR®) should be used, with 4 to 5 kg (8 to 11 lb) of NaPCP added for mold prevention in each 1000 liters (264 gal) of solution. 2. Because heated solutions yield better results and steam heat is often readily available, the treatment solution should be maintained at 50° to 60°C (122° to 140°F). 3. Dip time.--A minimum time of 1 minute is suggested. 4. Diffusion storage.--Boards should be placed on piling sticks immediately after dipping and stored under a roof or other cover for 1 week. 5. Other factors.--Low wood moisture caused by delay between sawing and treating or procedures used for piling treated lumber may affect the penetration of boron into wood and should be tested.

Citation

Williams, Lonnie H.; Mauldin, Joe K. 1985. Integrated Protection Against Lyctid Beetle Infestations Part II. - Laboratory Dip-Diffusion Treatment of Unseasoned Banak (Virola spp.) Lumber with Boron Compounds. Res. Note SO-313. New Orleans, LA: U.S. Department of Agriculture, Forest Service, Southern Forest Experiment Station. 8 p.