Several tick sampling methods were evaluated for ixodes scapularis Say and Amblyomma americanum (I.) in oak-dominated mixed hard-wood, pitch pine-dominated, and mixed hardwood and pine forests in coastal New Jersey. Walking surveys were more efficient for collecting I. scapularis adults than dragging by a factor of > 2:1. In contrast, drag sampling yielded nearly twice as many A. americanum adults compared with walking surveys. I. scapularis subadults were rarely collected during walking surveys. A. americanum nymphs were collected from drags approximately 3:1 over walking surveys. Twice as many A. americanum larvae were obtained from drags compared with walking surveys. All developmental stages of A. americanum responded positively to carbon dioxide. Pitfall traps and leaf litter samples collected very few ticks. Tick distribution among habitats varied significantly with the sampling method chosen, and the relative ranking of sites with respect to tick abundance varied depending on the stage of tick sampled. Failure to recognize the biases in these commonly used sampling techniques can potentially lead to incorrect conclusions that can have significant adverse public health consequences.

The diurnal questing behavior of adult Ixodes scapularis Say and Amblyomma americanum (L.) were monitored in the field to determine whether ticks would be collected with greater frequency during certain times of the day and under certain ambient meteorological conditions. Temperature and relative humidity explained a significant amount of the total variation in tick collections. Although both species were collected during every period, I. scapularis adults tended to quest earlier and later in the day when temperatures were lower and relative humidity higher, whereas A. americanum were collected with greater frequency in late morning and early afternoon during periods of higher temperatures and lower humidity. Questing of I. scapularis adults was observed at temperatures as low as -0.6 degrees C, whereas no adult A. americanum were collected below 4.4 degrees C. The questing temperature threshold for I. scapularis adults observed in this study was below that reported previously. The implications of these temporal activity patterns on the assessment of disease transmission risk and sampling bias are also discussed.

Removal of leaf litter in wooded areas of a forested residential community significantly reduced the abundance of questing blacklegged tick, Ixodes scapularis Say, nymphs throughout their peak activity period. Removal of leaf litter, using hand rakes and leaf blowers during the early spring (March) and early summer (June) resulted in reductions in nymphal tick density ranging from 72.7 to 100%. Subsequent sampling of the I. scapularis population during the summer revealed similar rates of suppression of larvae. Although leaf removal provides levels of suppression similar to more traditional methods, including chemical acaricides, it is labor intensive and not free of possible nontarget effects. The potential role of leaf litter removal in an integrated program to control I. scapularis is discussed.

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A single barrier application of granular deltamethrin to the woodland edges of a forested residential community in late spring significantly reduced the abundance of Ixodes scapularis Say nymphs. The application also suppressed the population of Amblyomma americanum (L.) nymphs, which recently became established in the study area. The efficacy of deltamethrin is compared with other commonly used acaricides.