We’ve reached that time of the year that we begin to see some Purpling in the leaf on our putting surfaces. Predominantly this is seen in Bentgrasses but it’s not unusual to see it in Poa either.
How it expresses itself in each grass species and biotype is very different and back in my days of managing some creeping bent greens that had a frustrating amount of Poa in them I’d see a whole range of colours some springs. At that point I believed it was a Phosphorus deficiency and did everything I could to try and mask it.
The last couple of years since I’ve been working with Ryder – which is Syngenta’s pigment I’ve learnt alot about the way the plant responds to various stresses. Using Ryder we’ve tried to use science to replicate the plants own defense process.
The purpling you see is the plant producing Anthocyanins to protect newer leaf tissue from the cool days and nights but a increase levels of light as a result of longer days and bright sunshine.
The production of Anthocyanins is a natural process the plant goes through when it’s under stress. Here’s a link to a fascinating article about Prof Sharon Robinson from the University of Wollongong, in Australia who is using the colour of Mosses in the Antarctic to measure climate change.
So after spending best part of two years talking to people about this lets see if the light and temp patterns from this year ties in with what we’ve been saying causes this?
You can see from the above two graphs that between 21st March and 5th April we saw a prolonged period of low minimum temperatures and high levels of light.
Since I’m not getting out into the field at the moment – let me know, if you’re seeing some purpling in the leaf right now send me a picture and your location and I may get a chance to see if I can tie down the climatic conditions and the period of delay before we begin to see this purpling of the leaf.
Here is a great article from Dr Danneberger (if you are reading – hope you’re fully on the road to recovery now) on this very subject.