OIPMC Degree-day Calculator

You can find OIPMC Degree-day Calculator here: https://uspest.org/dd/model_app

The OIPMC Degree-day Calculator is developed and maintained by uspest.org at Oregon State University’s Integrated Plant Protection Center.

Summary:

This tool provides a model estimate of phenological events based on degree days. This calculator, which has an agricultural focus, provides models for a selection of plants, insects, and pathogens. Several species invasive to the northeast and biocontrol species are included, such as:

Itadori (Japanese) knotweed (Fallopia japonica)

Wild parsnip (Pastinaca sativa)

Asian longhorned beetle (Anoplophora glabripennis)

Japanese beetle (Popillia japonica)

Spongy moth (Lymantria dispar)

Spotted lanternfly (Lycorma delicatula) 

Emerald ash borer (Agrilus planipennis)

Japanese knotweed psyllid (Aphalara itadori)

Black-margined loosestrife beetle (Galerucella calmariensis)

The OIPMC Degree-Day calculator uses public climate and weather data to calculate degree days that influence the timing of biological events like flowering and egg-laying.

First, you select their location in the “Station” tab. By clicking through to the “Model” tab, you can then select a general degree-day model or pick a species. Next, input dates and select a weather/climate forecast - you can choose to look at past averages, previous years’ weather, or choose from one of two future forecasting models.

The calculator then displays information about the model source and validity in the Output tab. You can also see a table of phenological events by degree day. Finally, the calculator displays an interactive graph of the model results under the Graph tab. The graph shows past degree days and predicted future degree days, with dots representing the predicted timing of phenological events. 

Behind the scenes, the calculator uses many sources for species models, which are identified in the “Model” tab. You can also learn more about the models and methods by clicking the “i” information buttons. Weather data come from public weather stations and the degree day calculation uses maximum and minimum temperatures. Of the future weather forecasts, users can choose between NMME or CFSv2. The NMME forecast is based on several models including the CFSv2. Here is a deep dive into the differences between the two options if you really want to get into the weeds (no pun intended!). 

Things to Try with this Tool:

  • Estimate when phenological events (e.g., emergence, flowering) will happen for a species in your area.

  • Check whether the past predictions for a species in your area line up with your own records or recollections.

  • Compare the predictions based on 1981-2010 average temperature with those based on observed weather patterns for 2024.

  • Download model data as a CSV for further use.

Keep in Mind:
The species models used haven’t all been validated to the same degree. You can see the validation status on the Model tab. Additionally, some species phenological models were developed for other regions and may be less accurate in the Northeast. Weather forecasting will continue to change throughout the year and season and will be more accurate for shorter timescales. 

Utility for Management:

View future degree day predictions for your specific management area and for species of relevance. This could be useful to plan management actions. 

See how degree days have changed in the past and are likely to continue to change due to climate change to inform longer-term strategies.

Video Introduction & Tutorial:

Check out the Tools Summaries and Tutorials playlist on our YouTube channel for a tutorial on how to use the OIPMC Degree-day calculator.

  • Navigating the website

  • Viewing historical averages

  • Viewing predictions for degree days generally and for individual species

  • Exploring and downloading data