For each sample date in the 1985 and 1986 soybean fields, the

 variance/mean ratio of adult and nymphal populations are presented in Table 1.

 Variance/mean ratios of <1, 1, and >1 represent uniform, random, and clumped

 distributions, respectively (Southwood 1978). According to this measure of

 dispersion, nymphal populations were aggregated on 55.8% of the field/date

 data sets when data were sufficient for analysis. Adult populations were

 aggregated 47.1% of the time. Values were >1, but not significantly greater

 than 1, on most other dates for both nymphs and adults.

 Taylor's power law relates variance (s2) to mean density (m) by the

 relationship, s2 = amb. Taylor et al. (1978) considered the slope (b) to be a

 constant for a species (with values of b<l, b=l, and b>l indicating uniform,

 random, and clumped distributions, respectively) and the intercept (a) to be

 reflected by sample-unit size. Taylor's power law is a particularly useful

 dispersion index, because it allows for a description of a species

 distribution pattern as changing with density.

 Regression statistics of Taylor's power law relationships for bigeyed bug

nymphal and adult sample estimates for each soybean field and for each year

are shown in Table 2. For all relationships involving nymphal populations, b

was statistically > 1(P < 0.05) according to t tests. These values of b and

the relatively high r2-values (mean = 0.94 and 0.94 for 1985 and 1986,

respectively) indicate that bigeyed bug nymphal populations were aggregated

over a wide range of population densities. Results were less definitive for

adult populations, with b statistically > 1 for 1 field. For 3 fields, b was

very near 1, strongly indicating a random distribution. The precision of the

regression relationships was good, with mean r2-values of 0.76 and 0.74 for

1985 and 1986, respectively.