1. Educational Information: Growing Degree Days (GDD)
What is GDD?
GDD is a crucial metric in understanding the growth patterns of plants, including turf grass, and is invaluable for optimizing maintenance strategies and predicting developmental stages. GDD measures the accumulation of heat over a specified threshold temperature, typically between 0°C and 30°C (32°F to 86°F), which is the range most relevant to processes such as seed germination, plant growth, and pest development.
How is GDD Calculated?
GDD=(MaxTemp+MinTemp)/2−BaseTempGDD=(MaxTemp+MinTemp)/2−BaseTemp
Negative values are truncated to zero.
Typical temperature range: 32°F–86°F (0°C–30°C).
2. Accessing the GDD Trackers
To create, pause, restart or archive GDD trackers:
Open the GreenCast Connect app.
Navigate to Settings (tap the gear icon ⚙️).
Select GDD Trackers to access the page displaying active or archived trackers.
3. Adding GDD Trackers
You can add customized GDD trackers to your dashboard by tapping the plus sign (+) in the top-right corner of the screen. This allows you to create trackers with the following parameters:
Tracker Name:
Assign a name to help identify the tracker.
Tracker Type:
Choose the type of GDD tracker (e.g., turf or pest).
Threshold Type:
Set the threshold type to align with specific tracking needs (e.g., accumulated GDD or calendar days).
Threshold:
Choose your actionable threshold for accumulated GDD.
Base Temperature:
Enter the baseline temperature used for GDD calculation.
Start Date:
Specify the date when GDD tracking begins.
Selected Target Species:
Link the tracker to monitor:
Annual Bluegrass
Bermudagrass
Creeping Bentgrass
Fine Fescue
Kentucky Bluegrass
Kikuyugrass
Perennial Ryegrass
Seashore Paspalum
St. Augustine
Tall Fescue
Zoysia
4. Active and Archived GDD Trackers
Active and archived trackers will display on your dashboard.
Ability to pause, restart, or archive the GDD tracker as needed by selecting it in the dashboard or under Settings-GDD Trackers.
Once a tracker is created, you can only edit the threshold days.
Edit the GDD threshold directly within the tracker settings for more accurate monitoring.
You cannot edit any other aspects of the tracker once it is created, but you can create a new tracker with updated settings if needed.
Note: once a GDD tracker is archived it cannot be undone.
Applications of GDD Trackers
GDD values can enhance turfgrass management strategies:
PGR Timing:
Plan plant growth regulator reapplications based on accumulated GDD.
Application Frequency:
Determine optimal timing for treatments by tracking GDD since the last application.
Pest and Disease Management:
Monitor pests with specific GDD thresholds for development and activity.
5. Viewing GDD Data
To view your active GDD Trackers:
Navigate to the Dashboard page in the GreenCast Connect app.
Ensure your GDD Tracker Widgets are activated:
Tap the plus sign (+) at the top-right corner of the Dashboard page.
Tap the plus sign (+) at the top-right corner of the Organize Dashboard page.
Confirm that the relevant GDD Trackers are selected and active.
Tips:
Set Accurate Base Temperatures: Ensure base temperatures match the specific needs of your turfgrass or target pests.
Use Multiple Trackers: Add GDD trackers for different species or management goals.
Monitor Regularly: Review active GDD trackers to adjust your maintenance strategies as conditions change.
