Getting more from an acre could ease land pinch

One way to stretch precious land among an increasing number of uses is to boost its productivity, experts say. But crop, forestry, and other specialists say more research is needed on:

* Developing genetically improved tree seeds, and learning how much wood different trees produce and when it is most profitable to cut them.

* Learning how to put land to more than one use at a time: for example, grazing and timber, or two crops a year.

* Finding the most productive use of land in various areas. The US Department of Agriculture is already using computers to simulate Western range land in studying soil, water, and insect problems. Such studies will be adapted to Southern land to determine whether particular areas would be more productive for crops, grazing, or timber.

* Gaining better control over crop-destroying insects. The USDA has begun using radar in the South to scan the atmosphere for insect migrations.

Some methods of increasing land productivity are known but need to be used more, specialists say. They cite greater use of erosion control and private and federal tax incentives to help small timberland owners harvest their trees profitably.