26th March – Mini Update
Hi Guys,
Just a quickie (story of my life) update to mention that we’ve got some good growth coming from the weekend onwards and with any luck for most of you this will extend nicely into next week, if you look at the chart below for a number of locations across the U.K and Ireland.
The key is some good night temperatures from Saturday onwards which will take the ‘handbrake’ off growth for both Bent and Poa species in my mind…
The graph above is downloadable here
What it shows is the value of GDD usage from a predictive perspective because we are looking at a growth flush and then nice gentle growth, fueled by Spring ‘sunshine and showers’ weather next week.
This may indeed also trigger some Fusarium but since we’ll have the growth as well, you should cut out most of the active disease without requiring a fungicide hit hopefully, but be on your guard nonetheless.
So if you’re sitting there with mottly greens, with the bent growing, the Poa sitting there not quite ready to wake up, this growth period should get things moving nicely especially if you have your nutrition in place.
The reason I’ve sent this through on a Wednesday is that you still have time to react before the weekend. So if I’m looking to kick the greens on after aeration, then I’d expect to use a granular product prior to the weekend to achieve this, if you have one down already, you should see a nice response from the weekend onwards through next week.
If you have a good surface, but you’ve lost some colour of late with the frosts on Monday morning and since, then a light liquid tonic using low temperature N forms (ammonium sulphate, nitrate, potassium nitrate, etc) with iron will work really well to bring in the colour and most importantly uniformity.
Enjoy a ‘normal Spring’ for the next 7-10 days or so 🙂
By the way, being a sad b*****d I looked at the GDD figures for 2014 and 2013 and discovered that my Hedgehogs came out of hibernation more or less exactly at 95 GDD, measured since Jan 1st. Sad for them to know that they’re part of a scientific experiment !
regards
Mark Hunt
Glenn Kirby
Just started to see seedheads on annual biotypes yesterday – 159 GDD (I think?)
Any chance of putting up a link to your GDD pdf or an e-mail.
Thanks
Glenn
Hockley GC
South Coast
mark.hunt
Hi Glenn,
Thanks for the feedback.
Do you mean a link to the GDD talk pdf I did at Harrogate, if so I’ll sort, but the blog will be late this week cos I’m swamped !
Mark
Jason brooks
Hi Mark, saw my first seed heads on the greens this morning would you say that is an indicator that I could start with the primo applications ?
mark.hunt
Hi Jason,
A good question, but obviously Primo has no effect on seedhead production though there is a suggestion that it makes the site of seedhead production lower down in the canopy by shortening the plant. This may or may not be a good thing because it makes the seedheqads harder to remove by brushing / grooming if they’re closer to the crown of the plant IMHO.
The first seedheads are usually the annual plants present on clean up strips, walk on / walk off areas, with the bulk of the seedheads following 7-10 days behind. Looking at the GDD for The Oxfordshire, if we hit the next 7-10 days air temperatures as expected, we won’t be far off 150 cumulative GDD since Jan 1 and that’s my marker in the sand for the main Poa seedhead flush.
So for me I reckon we’re 7-10 days away from PGR applications on greens, but I’d be light rate because April and May will not be consistent growth periods, they never qare, so you should be prepared to stop PGR applications if temperatures and growth drops back.
Mark
James Sergeant
Hi Mark
Similar request to Billy, could you send me through a copy of your GDD talk
James
mark.hunt
Hi James,
No problem, making a pdf copy now, so I’ll add you to the list.
Mark
Matthew Nutter
Hi Mark – great post (again)
I have started recording GDD here at East Berks since your talk at BTME. I am using 6⁰C as my base temp, is this correct?
I have already noticed a huge difference between this years and last years figures, I make It we are over 100% up on last year.
Look forward to hearing from you
Regards
Matt
mark.hunt
Hi Matt,
Yep 6C is the base temperature, and yes again, we’re already double last year, but then it was a very cold Spring.
Not sure if you’re aware but we have a downloadable spreadsheet that calculates GDD automatically, see the link below.
All the best.
Mark
https://weather.headlandamenity.com/wp-content/uploads/2014/02/GDD_GP_Annual_Log.xls
Billy hudson
Hi mark , any chance I could get a copy of talk on GDD, never managed to get down to Harrogate, heard many great thinks about your talk.
Regards Billy
mark.hunt
No problem Billy, I’ll email a pdf copy to you in the morning.
Mark
Alan Gee
Hi Mark
I’ve been talking to Angus and he’s keen for us (The Belfry) to start recording our GDD can you please send me the formulas you use and an other info you think maybe useful to me so I can get started with it
Regards
Alan
mark.hunt
Hi Alan,
I’ve sent a copy of my latest talk, it explains GDD, shows the calculation and some examples of how you can use it.
I’ve also attached the spreadsheet which Paul put together that automatically calculates your GDD once you’ve entered minimum and maximum air temperatures.
Hope that helps..
Mark
Gerry Bruen
The data is excellent Mark.
mark.hunt
Cheers Gerry, much appreciated…