ABSTRACT
The influence of three overwintering habitats on boll weevil ecology has been investigated in detail in the Texas Rolling Plains. These habitats are shelterbelt, sand shinnery oak, and mesquite litter. Shelterbelt architecture can be modified to reduce the threat of boll weevils to adjacent cotton production. However, most of the original shelterbelts no longer provide adequate winter habitat, and the primary significance of shelterbelts is that they aided in the original establishment of the boll weevil in the Texas Rolling Plains. Sand shinnery oak provides one of the best winter habitats, and it covers extensive areas in the southern and western regions of the Rolling Plains. Winter survival tends to be higher in shinnery mottes, and spring emergence is delayed by cooler temperatures in mottes as compared to emergence in low shinnery brush. Mesquite may be the most important overwinter habitat in the Rolling Plains because it occupies nearly 8.5 million acres of land. Spring emergence terminates sooner from mesquite litter as compared to that from broadleaf litter in both the southern and northern Rolling Plains. The shallow litter layer and thin canopy cover of mesquite allow rapid heat accumulation in the litter. The delayed uniform planting tactic eliminates mesquite as an effective overwintering site for the boll weevil. Most emergence from mesquite is suicidal because spring emergence terminates before squares become available as an ovipositional site.
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