Characteristics of cotton fields sampled for western tarnished plant bug, Lygus hesperus.

Variables shown are average field area (ha), average closest distance between pairs of sampled cotton fields (km), date of initiation of first and second sampling periods, average date of initiation of flowering, percentage of sampled fields planted to Pima cotton, average number of insecticide sprays and average Lygus density (calculated per 100 sweeps to facilitate comparison with thresholds) for combined sampling periods in each year.*Number of fields sampled: 41 in 2007; 39 in 2008; 56 in 2009.†Standard error in parentheses.‡Date is for onset of sampling period; number of weeks sampled per period is in parentheses.¶Range associated with average flowering date was 22 Jun–7 Jul in 2007, 7 Jul–12 Jul in 2008, and 17 Jun–2 Jul in 2009.§Suggested thresholds for Lygus spraying depend on cotton phenology [48]. Number of individuals per 100 sweeps that would trigger spraying is: >4–8 adults (early squaring); >14–20 individuals with at least two nymphs (bloom); and >20 individuals with nymphs present (boll filling).