Can Direct Seeding of Pine Be Improved? In the past, the replanting of burned-over or clean cut forest areas has been done by the somewhat slow and laborious method of individual planting of seedlings which had been raised in tree nurseries. Direct seeding in such areas had proven unsuccessful because birds and rodents would help themselves to this ready supply of food before the seed could germinate. Now, discovery of a bird and rodent repellent that can be easily applied to longleaf pine seeds before sowing is- making the direct seeding of trees practical and inexpensive.
The repellent, composed of tetramethyl thiuram disulfide, is not harmful to birds or animals in the amounts used and does not retard germination of the seed. Although it is slightly irritating to the eyes, nose, and throat of humans, it is safe to use, according to studies made by the Alexandria Research Center of the Forest Service and the U. S. Fish and Wildlife Service.
Direct sowing of tree seeds is the cheapest way to plant. Foresters, however, still advocate setting out seedlings because it is a simpler procedure for most people and more predictable. But seeding is becoming more foolproof and in another few years should be more generally accepted. Seeding costs about $ 8. 50 per acre compared to $ 12 per acre for planting seedlings.
Does Age Affect Strength of Wood? A test of the floor joists of the Octagon House, Washington, D. C. , shows joists that were cut form virgin Southern yellow pine of high quality to be as strong as when they were installed more than 150 years ago.
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