Rapid and accurate estimations of the heterotrophic and autotrophic components of total soil respiration (Rs
) are important for calculating forest carbon budgets and for understanding carbon dynamics associated with natural and management-related disturbances. The objective of this study was to use deep (60 cm) root exclusion tubes and paired control (i.e.
, no root exclusion) collars to estimate heterotrophic respiration (Rh
) and Rs
, respectively, in three 26-year-old longleaf pine (Pinus palustris
Mill.) stands in western Georgia. Root biomass was measured in root exclusion tubes and control collars after 102–104 days of incubation and fine root biomass loss from root exclusion was used to quantify root decay. Mean Rs
from control collars was 3.3 micromol·CO2
. Root exclusion tubes decreased Rs
, providing an estimate of Rh
. Mean Rh
was 2.7 micromol·CO2
when uncorrected by pretreatment variation, root decay, or soil moisture compared to 2.1 micromol·CO2
was corrected for root decay. The corresponding ratio of Rh
ranged from 66% to 82%, depending on the estimation method. This study provides an estimate of Rh
in longleaf pine forests, and demonstrates the potential for deep root exclusion tubes to provide relatively rapid assessments (i.e.
, ~40 days post-treatment) of Rh
in similar forests. The range in Rh
is comparable to other reports for similar temperate coniferous ecosystems.