A day late because I’m working up in Scotland at the moment and this afternoon I’m doing a talk at The Scottish BIGGA Conference so time is tight, my apologies. I happened to arrive in Scotland on a cracking early Spring day. The views across to the mountains of Arran and Ben Lomond, at the courses I visited were spectacular.
You’re probably wondering after last week’s rain: when we’re going to get a decent break in the weather, particularly for those guys down south?
Well, I am the bearer of potentially good news for some of you (particularly in the southern half of the U.K. and Ireland) because the answer is this week and at least some of next. Not only do we have some drier weather courtesy of that Atlantic high pressure I mentioned last week, but it’s also a warm high, which will funnel up warm winds from the south by the end of the week, it wouldn’t surprise me if we hit 15°C by the latter part of the weekend, so dig out the factor 30 and those shorts (leave your Desert Rat replicas in the cupboard Michael for the sake of office harmony :)). Now hopefully this change will really start to ramp up the E.T. rates and dry some surfaces out. (In the south)
General Weather Situation
Ok so where are we at present?
Going into Tuesday, that low pressure that gave us rain at the weekend will be moving away but still affecting the north of the U.K. and Ireland. We have some rain affecting the west coast of the UK and Donegal, falling as wintry showers over higher ground and this rain will move eastwards across Scotland during the day. Elsewhere we look to have a dry day on the whole: some scattered showers / lighter rain affecting the north-west coast of England, but dry and slighter warmer in the sun for Tuesday. Winds again will be westerly and light. Aside from Donegal, Ireland looks to have a drier day for Tuesday until the beginning of the afternoon when a rain front will push into Kerry and track north-east towards Leinster, fizzling out as it does so.
Wednesday looks dry again on the whole, with slightly stronger south-west winds (we need the wind to dry things out) and there’ll be some sun around, mainly over central areas of Ireland and the U.K. This must be one of the first days when I can’t see any rain around, except for the far north-west of Scotland, where there’ll be showers through the day.
Thursday starts off in a similar manner, but early doors a rain front pushes onto the west coast of Ireland and Scotland, potentially heavy in north-west Scotland. This slowly moves across Ireland during the day and pushes into the west coast of the U.K. by the morning rush hour, so a wet start here. Through the day, that rain intensifies over Ireland but, by and large stays isolated to the west coast. Elsewhere it’ll be dry with hazy sunshine and temperatures hitting double figures in a southerly breeze. A tad warmer at night as well.
Overnight into Friday, the rain front pushes southwards into The Midlands, north of England and eventually southern and central England, but as it does so it’ll fizzle out, so I don’t expect high rainfall amounts. It’ll still be sitting over the north-west coast of Scotland as well, failing as wintry showers here over higher ground. Temperatures will again be high single / low double figures, but they’ll be more cloud cover around due to that rain front. The rain should dissipate as we go into Friday night.
The outlook for the weekend looks pretty good for most areas of the U.K. and Ireland and, for a lot of you, you’ll really notice the temperatures rise on Sunday. I wouldn’t be surprised if we get to mid-teens by Sunday in the south of England for instance. Winds will be southerly and moderate. There’ll be a rain front pushing into the west coast of Ireland later on Saturday and overnight that’ll also affect western and central Scotland during Sunday, but east and south of this (That means east Leinster, Munster should stay dryish though it depends how far it pushes eastwards) it’ll be a nice with hazy sunshine, a southerly wind and if the sun breaks through those temperatures will really pick up.
Ok, so how are things shaping up next week? in a word, Mega!
Well ok, I have to be cautious here, we all know the weather can change, because seeing a high pressure establish for the first time since last November would be brilliant for us all, but as I look at Unisys projections, that’s how it looks. The high is set to build from the weekend, pull warm air up on southerly / south-easterly winds and that’ll mean warm temperatures, a dry weather window, with the low pressure systems pushed up over us. Now we all know this could change, but let’s see when we come up to Monday’s blog (I’ll be back to normal and home by then :))
Downloadable GDD Spreadsheet
Firstly, some of you may have missed the downloadable Growth-Degree-Day spreadsheet, Paul put together a couple of weeks ago, so If you did, you can go to here to download it
With the anticipated increase in temperatures from Sunday and next week, this may kick off some Fusarium activity, but I have a theory and you guys can help me if you wouldn’t mind by posting some feedback to the comments section on the blog. The main disease activity period last year was late summer, early autumn and for most, the onset of the cooler weather in November knocked it on the head. I’ve had very few reports of active disease aside from where Microdochium established during this period and then flared up around the edge of the patch in the milder temperatures of early January (see image right)
I’m interested to see what happens when the temperatures pick up, will we see new active Microdochium? If so, where will it occur across the greens surfaces you manage? My hunch is that any new Microdochium will occur on drier greens or on the drier part of greens (noses, mounds, tiers, etc.). If you don’t mind, drop me an email or post a comment on your experiences, it’s all grist to the mill and useful I can assure you.
Interesting one this, particularly this year when we’ve had such a mild winter, with very few frosts and very little likelihood of many more I guess? If you look at the GDD data for February from The Oxfordshire, we had 17 positive growth degree days out of a possible 28. Now of course early on in the month, day length and low light levels will have limited the potential of the plant to grow, but as we went through February and the days stretched out, the growth has definitely picked up, particularly on higher-height of cut areas like fairways, sports pitches, etc Comparing 2014 with previous years, January was on a par with 2011 and 2012 and February a little behind….
If you look at the cumulative figure for 2014 vs. previous years it gets even more interesting….
At the end of February 2014, we reached a total of 55.5 D °C (Cumulative degree days starting on January 1st =28.5 for Jan2014 + 27 for Feb2014), comparing that to 2013 and 2012, I can see the following ;
In the warm spring of 2012 (when we were under a warm peak in the jet stream) we reached the same cumulative GDD figure of the 23rd February, so we’re 1 week behind 2012 in terms of growth stage,
In contrast, during the very cold, prolonged spring of 2013 (when we were under a cold trough in the jet stream) we reached the 55.5 – Cumulative GDD figure on the 14th April, so currently we’re tracking 6 weeks ahead of 2013 using GDD data! Interesting is it not?
All this gets me thinking about when and where we should start PGR applications and for me the default position is when your grass species are growing and you’ve achieved recovery from winter wear and tear. There’s absolutely no point in my mind in growth-regulating tees for example before you’ve achieved this recovery and have a good surface. In the U.S, they work on a different GDD model for applying Trinexapac-ethyl, using a base temperature of 0°C and a total GDD figure of 200, which roughly translates to 80 using my model. The 200 GDD figure concerns repeat applications i.e. you make a TE application and then when the plant has grown through 200 GDD using their calculations, you re-apply. It’s an interesting concept and there’s some good data around to back it up, see the link here You can also see that they saw no difference by doubling the labelled rate on TE in terms of growth suppression and longevity of effect, but you must treat this with caution because we’re dealing with primarily Poa (they’re working with Bentgrass) and their climate is much more stable than ours.
The question in my mind is when do you start though?
If we take the 80 GDD figure using my model and look at previous years data, that means you’d have started using a PGR (on higher height of cut turf) on the 5th March in 2012 and the 14th April in 2013. (using data from The Oxfordshire). That’s too early in my mind because looking at data from last year, good growth didn’t actually start until the 12th April, so that means the plant will have had 2 days to grow properly before you started regulating it. So 80GDD is too early, I think we’re going to be somewhere around 125GDD before starting TE applications on higher height of cut turf and maybe also on shaded turf areas like greens.
In this scenario you have a plant growing in low light conditions and it stretches up towards the light, elongating as it does. (Just like when you grow seedlings on your window sill, they go leggy after a while)
If you fertilise heavily, it only increases this effect and in addition uses up the plant’s carbohydrate reserves very quickly (which it will struggle to replace due to poor photosynthetic efficiency in low light). So if we regulate here, earlier, we may see some advantage in terms of sward vigour and density. Obviously that goes along with minimal organic matter removal (Why remove organic matter from a shaded green when the plant struggles to produce it in the first place?), minimal verticutting, scarification, instead concentrating on brushing, solid tining, topdressing and vertidraining at the appropriate times of year. I’d also be looking to raise the height of cut, maybe by 0.5mm on shaded greens.
All hopefully food for thought, ok it’s time for me to engage with the Scottish Conference, do my prep and cross everything 🙂
Have a good week and Happy Pancake Day, I’ve decided to give up Costa Coffee’s for Lent. What’s that? yep, a De-Caf – Flat White for me please luv… Ah well that didn’t last long 🙂