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
Elm leaf beetle. IN: Pests of Landscape Trees and Shrubs: An Integrated Pest Management Guide. University of California Statewide IPM project. Div. Agr. Publ. #3359
- Location of study: California (field studies)
- Lower developmental threshold: 51.8°F (11.0°C)
- Method of calculation: Single Sine
Degree-day accumulations required for each stage of development
Start date: March 1
Host: English Elms - First Generation
- Begin monitoring egg density: 360.0 (°F) 200.0 (°C)
- Peak egg density: 510.0 (°F) 283.3 (°C)
- Peak first & second instar larvae density: 700.0 (°F) 388.9 (°C)
- Trunk spray or bark band application*: 700.0 (°F) 388.9 (°C)
Host: English Elms - Second Generation
- Begin monitoring eggs density: 1565.0 (°F) 869.4 (°C)
- Peak egg density: 1715.0 (°F) 952.8 (°C)
- Peak first instar & second larvae density: 2000.0 (°F) 1111.1 (°C)
Model 2
Dahlsten, D. L., S. M. Tait, D. L. Rowney, and B. J. Gingg. 1993. A monitoring system and development of ecologically sound treat- ments for elm leaf beetle. J. Arbor. 19: 181-186.
- Location of study: California (field studies)
- Lower developmental threshold: 51.8°F (11.0°C)
- Method of calculation: not specified (UC IPM recommends Single Sine)
Degree-day accumulations required for each stage of development
Start date: March 1
Host: English Elms - First Generation
- Begin sampling weekly for egg masses: 329-419 (°F) 183-233 (°C)
- Eggs 509 (°F) 283 (°C)
- First instar larvae 635 (°F) 353 (°C)
- Second instar larvae 794 (°F) 441 (°C)
- Third instar larvae 857 (°F) 476 (°C)
Host: English Elms - Second Generation
- Begin sampling weekly for egg masses: 1535-1625 (°F) 853-903 (°C)
- Eggs 1715 (°F) 953 (°C)
- First instar larvae 1962 (°F) 1090 (°C)
- Second instar larvae 2055 (°F) 1142 (°C)
- Third instar larvae 2129 (°F) 1183 (°C)
Model 3
Dreistadt, S. H. and D. L. Dahlsten. 1990. Relationships of temperature to elm leaf beetle (Coleoptera: Chrysomelidae) development and damage in the field. J. Econ. Entomol. 83: 837-841.
- Location of study: California (field studies)
- Lower developmental threshold: 51.8°F (11.0°C)
- Method of calculation: Single Sine
Degree-day accumulations required for each stage of development
Start date: March 1
Host: English and Siberian Elms
- Begin monitoring egg density: 360.0 (°F) 200.0 (°C)
- Peak generation egg density: 495.0 (°F) 275.0 (°C)
