Electromagnetic Treatment of Loblolly Pine Seeds

Loblolly pine (Pinus taeda L.) is the species most frequently used for reforestation in the Southern United States; in fact, over 1 billion loblolly pine seedlings are produced each year for planting (McDonald and Krugman 1985). This has lead to a great deal of interest in any treatment that may have a potential to improve the survival and -early growth of this tree species. In the early 1970’s Sam Gray, Ph.D., patented an electromagnetic radiation seed treatment process (called the Gray Process) that claimed to speed seed germination, markedly hasten seedling growth, and provide disease control. Gray’s Energy Transfer Corporation (ETC) marketed the seed treatment as the Energy Transfer Process@ and promoted it across the South as a technique that would revolutionize agriculture. Some of the claimed results of using this process were (Helm 1976): 1. Yield of treated corn was increased by 161 percent, and in one variety the increase was reported to be 1,200 percent. 2. Soybeans showed a 300-percent increase in yield after treatment. 3. A crop of peanuts grown from treated seeds was 177 percent greater than one grown from untreated seeds. 4. Seedlings from treated loblolly pine seeds grown in a nursery had no disease or insect problems either in the nursery or in the field. 5. Treated loblolly pine seeds germinated in 3 days compared to 7 days for untreated seeds. 6. Loblolly pine seedlings grown from treated seeds showed increased growth; height and diameter growth was from 11 to 75 percent greater than seedlings grown from untreated seeds. An evaluation of seedlings grown from loblolly pine seeds treated with the Energy Transfer Process was conducted in 1978 (Hughes 1978). An increase in seedling survival and growth was reported after 2 years in the field. A few major forest industries made long-term arrangements to have large quantities of seeds treated (Runge 1975). However, controversy over the effectiveness of the process developed. Controls used in Hughes’ 1978 evaluation had not come from the same seedlot as those that had received the treatment. A test of a sample of seeds from the same lots Hughes had used showed no positive response from ETC treatments when tested by the USDA Forest Service in Pineville, LA. However, another study (Nelson and others 1980) reported that certain electrical treatments could influence germination rates. In 1979 the Forest Service agreed to conduct an impartial evaluation of the ETC seed treatment process. Testing was conducted by the Alexandria Forestry Center (AFC) in Pineville, Louisiana.