Objective 4

Objective 4. Determine Forest Composition, Basal Area, Density, Wood Volume and Age.

We propose to excavate accessible areas to create plots useful for measuring several stand-level characteristics. We plan to do this in a systematic fashion using rectangular plots that will facilitate restoration of the landscape at the conclusion of the study. Within the exposed areas, we will measure the diameter of each stump and determine its identity from wood anatomy.

Within the target areas are stems up to 0.8 m diameter. We propose to excavate and measure 25-30 stems across a variety of size classes which are unequivocally related to identifiable stumps. These stems will be excavated in addition to the 20 plots described above, using available opportunities. The dimensions and taper of the stems will be used to 1) create a regression relating diameter at breast height (dbh-the standard for reporting stand basal area) to stump diameter; 2) create regressions of stem height and volume on stump diameter. The latter is used to estimate stand stem volume from the measured stumps, and is equivalent to the standard for determining stem volume from diameter at breast height (dbh) in modern forests (e.g. Vann et al. 1998). Example of the precision of these relationships for Fitzroya cupressoides and Pilgerodendron uvifera and some of their uses is included in the paper by Vann et al. (1998). These relationships are generally robust, and are expected to produce estimates of plot stem volume (Vann et al. 1998) acceptable by reasonable standards (e.g. ± 15-20%).

We note that the uppermost portions of the stems seldom remain intact which will lead to difficulty in reconstructing heights, but there are anatomical indicators of tree height (see objective 8 below) which will help constrain height reconstructions. Relatively little mass is contained in the top of the stems, so that the effect on calculated stand biomass is expected to be small.