The effect of interplanting collards with a mixture of herbs on oviposition of the imported cabbageworm, Pieris rapae (L.), was investigated at Chesterfield Co., Virginia during 1981 and 1982. Analysis of the dispersion indices of the insect using Taylor's power law and Iwao's model revealed that P. rapae eggs were significantly — m (P < 0.001) clumped (b > 1) on collards interplanted with herbs. However, insect counts on control collards conformed to the Poisson distribution (b = 1, P > 0.05). Pieris rapae laid significantly (P < 0.01) more eggs on collards hidden between sage than on collards hidden between other companion plants. Also, P. rapae laid significantly (P < 0.005) more eggs on collards bordered by companion plants than on non-bordered control. These data suggest that companion herbs did not repel P. rapae but instead significantly encouraged colonization of the insect and produced an aggregated distribution.

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Can. Ent. 115: 1523Ent. 115: -1527Ent. 115: (1983 Required sample size was determined for early instar (2nd to 4th instar) larvae of spruce budworm, Choristoneura fumiferana (Clem.). Larval counts on mid-crown 45 cm branch tips and whole branches of balsam fir, Abies balsamea (L.) Mill., were described in terms of the negative binomial distribution. The values of common k for the branch tip and whole branch sample units were 1.550 and 1.636, respectively. The required sample size at densities greater than or equal to one appears feasible. It is recommended that the 45 cm branch tip be used to estimate population density of early instar larvae in Newfoundland. ResumeLa taille requise de 1'Cchantillon pour les jeunes stades larvaires (2. a 4.) de la tordeuse des bourgeons de I'Cpinette, Choristoneura fumiferana (Clem.), a Ct C dkterminke. Les nombres de larves comptCes au milieu de la cime sur les 45 derniers centimktres des branches et sur des branches entikres du sapin baumier, Abies balsarnea (L.) Mill., ont Ct C exprimCs suivant une distribution binorninale nbgative. Les valeurs du k commun pour les Cchantillons de bouts de branches et de branches entikres sont de 1,550 et 1,636 respectivement. Obtenir un Cchantillon de taille requise a des densitCs Cgales ou supCrieures 2 1 semble rkalisable. I1 est recommand6 d'utiliser les 45 derniers centimktres des branches pour estimer la densit6 des populations des larves aux premiers stades Terre-Neuve.

‘California Wonder’ pepper was transplanted on May 15 at Virginia State University’s Randolph Farm, Chesterfield Co., VA. Soil type was a Goldsboro fine sandy loam. The field plots were assembled as a randomized complete block design with 4 rows, each 3 m long. Pepper was planted in one of these rows while eggplant, collard and squash were planted in the remaining 3 rows. These plots were replicated 4 times with 1.5 m alley between plots. The pepper plants were treated 2 wk after planting with a piston pump sprayer mounted with a single hollow cone nozzle. Spray solutions were prepared at the rate of 100 gal/acre. Spraying was initiated on May 20 and was continued at biweekly intervals thereafter until a total of 5 sprayings were completed. Peppers were harvested on Jul 14, 21, 27, Aug 5, 18, 31 and Sep 15. On each sampling date, number of fruits infested were counted and the data converted to arcsin-%transformation. These data were pooled and variance analysis was performed.