Variation in Seedbed Moisture Correlated with Growth of Pinus taeda Seedlings

Abstract

Seedlings of P. taeda were grown in a seedbed under the open-rooted system to obtain growth data to regress against variations in soil moisture tension. From July through October, frequent rains kept soil moisture levels high and made irrigation unnecesary. Variations of mean soil moisture tension within the seedbed ranged from 3 to 11 kPa. Seedling growth was measured by destructive sampling in October. Root collar diameter, total height, and dry weight of shoots all increased with increasing mean soil moisture tension. This study indicates that growth of P. taeda seedlings may be reduced when soil is kept in a saturated condition (mean soil moisture tension < 10 kPa for this study).