The last couple of years we've seen some real turf disease pressure over the Christmas period.
I talked about the Moisture / Temperature relationship in one of my recent Blogs and thought it was a good chance to pull the data out for where I am down South compared to last Christmas.
Each dot on the graphs shows the average leaf wetness figure and temperature for the the hour. (24 dots equals one day). There is an optimum temperature range for disease to manifest itself on our surfaces. We also need some leaf moisture so the disease can spread and move. No leaf moisture = no disease. Temperature outside of optimum means the disease won't move.
The more dots in the RedZone the longer the periods of high disease pressure.
You can see that down here in 2020 we spent a lot of time hovering around -2 to 5 degrees and a lot of that time we had 0 leaf moisture. Getting these break periods really slows development of disease down.
In 2019 however for the period between 24th Dec and the 30th Dec the temperature hovered around 5 to 10 degrees with high levels of leaf moisture throughout.
During these prolonged periods of high pressure even the most robust ITM programmes are tested.
So whilst Christmas 2020 will be remembered for many challenges, including excessively wet ground, full booking sheets, frustrated memberships and the complications of Lockdown, one of the blessings is reduced disease pressure compared to last year. (I'll continue to look for some positives where I can!) .