Tree dbh was compared for trees hosting and trees not hosting vines using
MinitabTM Statistical Software to calculate the Mann-Whitney test at the 95%
confidence level, as described by Eddison (2000).

 Basal area was calculated for each individual tree species and as a cumulative
over the entire site using the following formula (Avery and Burkhart 1994; Husch and
others 1993):


Basal Area =


 (dbh (cm))2 x 0.7854
Total Area of Elongated Quadrats


 Vine leaf area index ( an estimate of the # of leaves/m2). Vine leaf area was
calculated for each site using the following formula:

Vine Leaf Area Index = m2 leaves
 m2 ground


Abiotic Data Analysis


 Sunlight Transmittance

 Percent transmittance was calculated as:

% Transmittanceso = mean PAR at 50 cm above the forest floor x 100
 PAR outside of the canopy


 Water Depth

 Water depth was averaged for each site.


 Soil Moisture

 Percent soil moisture was calculated using the following formula:

 Percent Soil Moisture = Wet Weight (g) Dry Weight (g) x 100
 Wet Weight (g).


Bulk Density

The equation for bulk density of the soil follows:


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