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Crabgrass Germination Prediction (GDD 50)
through Tue, Jan. 28. 2020


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Latest Updates

March 9th, 2018Note Regarding 2018 Alerts

We had an issue with the emailed alerts that should be resolved now, and apologize for any inconvenience. You may receive outdated alerts tomorrow (Saturday, March 10, 2018), so please check the details before taking any action. Thank you.


February 17th, 2018Welcome to a New GDD Season!

GDDTracker is ready for 2018 with GDD tracking that began on February 15. New this year will be the Smith-Kerns Dollar Spot Prediction Model which will be launching soon. Check back soon for additional details!

March 29th, 2017Timing crabgrass pre-emergence applications

Please note that Dr. Frank has written another helpful article available from the MSU Extension web site.



March 9th, 2017Controlling Annual Bluegrass Seedheads: Spray Now or Wait?

Dr. Kevin Frank has posted a useful article at the MSU Extension website. Please note it is written specifically for Michigan but may apply to other midwest regions.

"Growing degree-days have accumulated quickly, but it may not yet be time to apply plant growth regulators to control annual bluegrass seedheads on golf courses.

Read more: http://msue.anr.msu.edu/news/controlling_annual_bluegrass_seedheads_spray_now_or_wait


February 26th, 2017Early Spring in Michigan: Boom or Bust?

Dr. Kevin Frank has posted a helpful article on the MSU Extension website. Much of the midwest is experiencing the same (very) early warm-up, so non-Michiganders may find it help as well!


February 16th, 2017Missing weather data

All air temperature data has been accounted for now.