Phenology models predict timing of events in an organism's development. For many organisms which cannot internally regulate their own temperature, development is dependent on temperatures to which they are exposed in the environment.
Information in this database comes from published articles. It may be used in conjunction with field monitoring and a degree-day calculator.
Note: Before using a model that was not field tested in your location, you should test the model for one or more seasons under your conditions to verify that it will work for you.
Model 1 of 4
Zalom, F. G., W. W. Barnett, R. E. Rice, and C. V. Weakley. 1992. Factors associated with flight patterns of the peach twig borer (Lepidoptera: Gelechiidae) observed using pheromone traps. J. Econ. Entomol. 85: 1904-1909.
- Location of study: California (10 years of field data)
- Lower developmental threshold: 50.0°F (10.0°C)
- Upper developmental threshold: 88.0°F (31.1°C)
- Method of calculation: Single Sine
- Cutoff method: Horizontal
Degree-day accumulations required for each stage of development
Biofix: First male moth captured in pheromone traps.
Host: Almonds and Stonefruits
- Single peak in flight: 369.0 (°F) 205.0 (°C)
- Bimodal peaks in a single flight
- First peak: 232.2 (°F) 129.0 (°C)
- Second peak: 676.8 (°F) 376.0 (°C)
- Generation time (adult to adult): 1080.0 (°F) 600.0 (°C)
- Springtime spray directed at overwintering flight*: 400.0 (°F) 222.0 (°C)
* See UC IPM Pest Management Data Base for most recent recommendations.
Model 2 of 4
Rice, R. E., F. G. Zalom, and J. F. Brunner. 1982. Monitoring peach twig borer development with degree-days. U.C. Div. Agr. Pub. #21302.
SEE ALSO: Rice, R. E., F. G. Zalom, and J. F. Brunner. 1982. Using degree-days in a peach twig borer monitoring program. Almond Facts March/April 1982: 60-62.
- Location of study: California
- Lower developmental threshold: 50.0°F (10.0°C)
- Upper developmental threshold: 88.0°F (31.1°C)
- Method of calculation: not specified (UC IPM recommends Single Sine)
- Cutoff method: not specified (UC IPM recommends Horizontal)
Degree-day accumulations required for each stage of development
Biofix: First male moth trapped; Set out traps: March 15 in southern part of Central Valley and April 10 in northern part of Central Valley
Host: Almonds
- Pre-egglaying adults + eggs: 220.0 (°F) 122.2 (°C)
- Larvae: 507.0 (°F) 281.7 (°C)
- Pupae: 333.0 (°F) 185.0 (°C)
- Generation time (adult to adult): 1060.0 (°F) 588.9 (°C)
Model 3 of 4
Peach twig borer. IN: Integrated Pest Management for Almonds. University of California Statewide IPM Project. Div. Agr. Sci. Publ. #3308.
- Location of study: Central Valley of California
- Lower developmental threshold: 50.0°F (10.0°C)
- Upper developmental threshold: 88.0°F (31.1°C)
- Method of calculation: Single Sine
- Cutoff method: Horizontal
Degree-day accumulations required for each stage of development
Biofix: When moths are trapped on two consecutive sampling dates; Set out traps: March 20 in southern part of Central Valley and April 1 in northern part of Central Valley.
Host: Almonds
- First eggs hatch: 220.0 (°F) 122.2 (°C)
Model 4 of 4
Brunner, J. F., and R. E. Rice. 1984. Peach twig borer, Anarsia lineatella Zeller (Lepidoptera: Gelechiidae), development in Washington and California. Environ. Entomol. 13: 607-610.
- Location of study: Washington and California (field and laboratory studies)
- Lower developmental threshold: 50.0°F (10.0°C)
- Upper developmental threshold: 88.0°F (31.1°C)
- Method of calculation: Single Sine
- Cutoff method: Horizontal
Degree-day accumulations required for each stage of development
Biofix: First adult from overwinter generation.
Start date: January 1
Host: Peaches and Nectarines
- Preovispositing adult: 50.4 (°F) 28.0 (°C)
- Ovispositing adult: 124.2 (°F) 69.0 (°C)
- Egg: 165.6 (°F) 92.0 (°C)
- Larva: 464.4 (°F) 258.0 (°C)
- Pupa: 288.0 (°F) 160.0 (°C)
- Generation time: 1092.6 (°F) 607.0 (°C)
