Not a lot of change this week – the weather has cooled so we have seen reduced growth, increased stress and some increased benefits of Primo Maxx to turf colour.
First time I’ve mentioned colour. It’s a low maintenance trial and colour hasn’t been top of my list to talk about. The figures haven’t shown too much either, until now.
The reduced cutting regime at the start of trial showed increased turf health, this benefit has reduced as the cutting heights were lowered.
The Primo treatments showed nothing for a while. This was interesting as we’d added no additional nitrogen so whilst we traditionally expect additional darkening of the sward – with no additional N we could have seen increased yellowing or an increased greening. What we did see was very little difference.
Thats until we went into a reduced height of cut – now we have some stress imparted on the turf we are seeing a clear seperation in colour. The more Primo – the better the colour response.
Turf quality is on a downward turn, worth remembering we’ve put this turf through some fairly extreme height of cut drops, we are due some additional feed and the weather has turned cold. The good news is despite no additional N the growth suppression we have achieved has not been at the expense of turf quality. (when reading this graph its worth taking a good look at the left axis – there is very little difference between these figures).
The temperatures have dropped of this week – the greyed out area at the end of the below chart show how we have moved into a cooler period. This in turn has elongated the windows between the GDD based applications.
The below chart shows a comparison between two different parts of the country. Assuming the programs started at the same time (17th April) you can see here the difference in applications to achieve the similar results.
I have zero’d the GDD figure for day 1 of the program to simplify the graph.
Primo impact on growth
Nothing new to add here form last week but you can see that the longer GDD application the smaller the variance of clipping yield reduction.
I think this is useful to know as if you’re trying to achieve consitent growth then using GDD application windows will help you achieve more consistent results. This is different to maximising suppression which is a different objective.
Here is my blog from last week about the Turf Lockdown trials.
Alternatively read all about it on the Syngenta Greencast website here.