Three proprietary groundline wood preservative formulations were applied to weatheredsouthern pine pole stubs initially treated with creosote. Under test were penta-gel, fluoridecreosote, and fluoride-arsenic formulations. The amount and distribution of pentachlorophenol or sodium fluoride after 1, 3, and 5 years of exposure were determined, as were decay patterns after 5 and 10 years of service. Residual toxicity after the 10-year exposure period was also determined using soil-block bioassays. After 8 years of storage and 10 years of ground contact, creosote control stubs were severely attacked by decay fungi. All three groundline applications deterred decay. The most effective was the fluoride-arsenic injection treatment. -- AATA