I hope you all enjoyed your brief taste of spring over the weekend and for some, the early part of this week as well because we’re now heading back into our familiar to all, cold temperature trough created by our old friend, the jet stream 🙁
So much cooler I’m afraid as we progress through the week and we will have some frequent rain in attendance to boot, all in all, not great for the 1st week of April.
On a positive note, It was brilliant to fly fish at the weekend (on another soggy Saturday morning) and see House and Sand Martins skimming the waves and feeding up on hatching midges after their mammoth trek from Africa to here. Likewise I also saw an Osprey take a good sized Rainbow Trout and he doesn’t even have to buy a season ticket you know, tut tut. He’s another African migrant that’s here for the summer, well when it arrives that is….
I think it will be one of those years when we sit cool through the spring courtesy of the jet stream trough pattern and then suddenly it’ll lift and we will go straight to summer in the course of a few days. We will see.
General Weather Situation
With low pressure sitting over us it’s no surprise that we start Monday unsettled with rain across Scotland and north west England. During the morning this rain moves northwards into most of Scotland and the eastern coastline of Ireland. At the same time we see another band of rain push into the south west of England and later in the morning the south coast pushing north into central regions and The Midlands during the afternoon. So most places are on for a dull day to start the week and most likely you’ll see rain as well. The only area that is likely to miss this rain is the west of Ireland (I don’t say that very often) and here you’ll see some sunshine as well. Temperature-wise, nothing to write home about with low double figures the order of the day and warmest across the west I think. Winds will be light to moderate and south westerly in nature.
Tuesday is perhaps the best day of the week temperature and rainfall-wise, but it won’t start off that way for north west England and Scotland who start the day with rain still in situ. Elsewhere it’ll be a dull, hazy, but dry start to the day and that’s the way it’ll stay with very few breaks in the cloud cover likely. That northern rain will fizzle out through the morning to leave a pretty much dry picture everywhere for Tuesday afternoon. Winds will be light to moderate and will swing round to the west and that’ll usher in some better temperatures with low double figures / low teens the order of the day. These may just lift higher if you are lucky enough to get some sunshine and that is more likely to occur across the west.
Overnight into Wednesday sees a band of rain moving into Western Ireland and crossing the country during the wee hours. By dawn this will have largely cleared Ireland but will now be sitting across the western coastline of the U.K, so The South West, Wales, north west England and Scotland will start Wednesday wet. Some of this rain may fall as wintry showers over higher ground, especially over The Highlands. That westerly wind will have more strength to it as well and by mid-morning it’ll be ushering more showers across Ireland and pushing that U.K rain over central and eastern areas. Through the afternoon that rain consolidates across Ireland and the U.K, so a wet end to Wednesday is on the cards I’m afraid. It’ll feel chillier on Wednesday as well with temperatures pushed down by that cooler, westerly wind and that means more in the way of wintry showers for Scotland and across The Pennines as well.
Thursday sees that rain sitting over north west England, Wales and across Ireland, though lighter and more scattered for the latter. Away from that band of rain you may start the day bright and cold on Thursday, but it won’t last as that rain sinks south into South Wales (there you are Debbie), The Midlands and Central England by lunchtime. Ireland also sees those showers ramp up again I’m afraid with bright spells and blustery showers your mix for the day. Scotland starts off Thursday with wintry showers across The Highlands, but these will sink south and fall as rain, some of it heavy along eastern coasts. Temperatures will be a little cooler still on Thursday as the wind swings round to the north west so only high single figures for April which is poor 🙁
We close out the week with a continued theme of unsettled conditions for Friday with rain, sunshine and blustery showers the order of the day just about everywhere. The wind direction will swing round to a more southerly aspect but it won’t feel warm because it’s pulling down air from Russia. So again only high single figures for Friday despite the lighter winds. As we progress through Friday morning we see a more concentrated band of rain pushing into south west Munster and slowly track north eastwards, falling as sleet or maybe snow over the Kerry Mountains. By the afternoon we have less rain around across the U.K and perhaps some spells of sunshine across the north west of England. By the evening you’ll see less rain, but where it is still falling it’ll likely turn to sleet and snow. This is more likely across The Pennines, The Lakes and The Highlands of Scotland.
So how is the weekend looking ?
Saturday may not be such a bad day but a lot will depend on where you’re located. So we see those bands of wintry showers still sitting over Northern England and Scotland. Ireland will have a more concentrated rain band pushing in overnight for Saturday and it’ll affect east Munster and Leinster initially before pushing north west through the morning into Connacht and Donegal. For the U.K we’ll see a reasonably dry picture with hazy cloud giving way to sunshine in central regions and this may even lift the temperature close to double figures in southern locations. The exception could be the south west of England which may catch some of that rain band that is due to affect Ireland from the off, so potentially a wet day there…Scotland looks to have a cold day with frequent wintry showers across the north east and Central Highlands. Winds are likely to be light for Saturday and still from the south west / south.
Sunday looks to continue that unsettled theme with a risk of rain, some of it heavy in the south of England and this could push up into central regions through the morning. Scotland looks to continue its association with those wintry showers along eastern coasts and The Highlands, whereas Ireland looks like a day of sunshine and showers. Still nothing to write home about temperature-wise with a continued cool theme to the weather especially where you connect with that heavy rain, sleet, snow or hail 🙁 .
A trough pattern and low pressure only mean one thing I’m afraid and that’s a continually circulating low pressure system that will dump rain on a regular basis I’m afraid. So we start next week with low pressure sitting south west of Ireland and that means it’ll funnel up cool, southerly air across the U.K. So Monday looks to be wet and unsettled again with potentially heavy rain for the south of England moving north up country during the day, the same for Ireland. This will be the pattern through the week till Thursday when the low begins to sink southwards and this will bring a more easterly wind to bear for the north of the country, possibly with snow I think for Scotland. By the end of the week there’s just a chance we will be back to a more south westerly-biased air stream and that means milder temperatures, but I still think ever-present rainfall 🙁
Lots to talk about this week as we have the first quarter’s GDD information to digest and I have a good number of sites who have submitted data (cheers to everyone)
First off we can take a look at our usual location data point of Thame, Central England (well Oxfordshire to be more accurate). Look at the figure for March, a total GDD of 19.5 vs. 27 for February and 28.5 for January. So we can see we’ve had less growth in March 2016 at this location than either of the previous two months and that’s because we’ve had a trough pattern in place for most of the month.
Next let’s compare March 2016 with the last 6 years and we can see that the monthly total of 19.5 is second lowest only to the long winter and hence late spring of 2013. So that’s why I was castigating Countryfile last week going on about what an early spring it is this year, sure thing in February, but no way Jose by March, me old mucker. A good March with mild temperatures and rainfall yields great growing conditions and the last time we saw that was 2014. If there’s a trend, it’s that March is getting cooler year-on-year.
If you look at the cumulative GDD till the end of March for this location you’ll see we are tracking at 75GDD, which compares with last year’s total, the difference is we had most of that GDD in January and February in 2016.
Let’s look at some other sites from around the U.K and Ireland….
Looking at some locations across the U.K, you can see that Milton Keynes appears to be a particularly chilly place to live !
You can also see that the adage “It’s grim up north” doesn’t always apply because York was the mildest location in January 2016 !
Watford’s closeness to the M25 and the concrete jungle of London can be the only reason why they sit 20% ahead of the next warmest site.
On a serious note it does strike you the variability between just these 7 sites scattered across the U.K and it’s indicative of why something in one area doesn’t always pertain to another from a turf management perspective. Poa seedheads would be one such parameter, more on that later.
Looking at the Irish locations you can see this spring has been much more consistent between the sites and actually the GDD totals from most of the Irish locations are similar to the U.K.
Valentia of course down in south west Kerry sits head and shoulders above every location, UK or Irish, but we must remember with that mild temperature comes rainfall as well and close to 600mm for the first three months of the year for this location !
The reason why Valentia is so mild is because it is on the south west air stream and so it is least-affected by cold weather from the continent. In particular the night temperatures are warmer during the winter in Valentia with very few frost days. See below ;
The coldest location (Milton Keynes) runs up 29 days of frosts in the first quarter of this year compared to just 2 for Valentia, some difference and look at the minimum air temperatures as well, quite some difference, particularly in March.
So looking at all this data we can conclude that we have all endured a slow March and to put it into some perspective, 5GDD in a day is a good growth day in the spring, so with many locations showing just 25GDD for the whole of March, we have had the equivalent of just 5 days of good growth during March 2016.
Poa annua – Seedheads and Rooting…
I took some cores last week from a golf club and decided to split them down to the crown tissue in order to determine if seedheads were being formed ‘in the boot’ as the Americans call it.
This phrase refers to the formation of seedheads down in the Shoot Apical Meristem area of the plants crown (that’s the point where new shoot cells are created) and it is here where the seedhead of Poa starts life. If you strip the plant down you should be able to see a swelling in this area which denotes the first signs of seedhead formation.
As you can see from this admittedly poor quality image above, the crown of the plant is white and consistent with no indication of seedhead formation. Nor would I have expected there to be a seedhead because we are nowhere the sort of GDD totals where we see the appearance of Poa seedheads.
I normally start to see annual Poa seedheads in higher height of cut areas at around 100GDD and then the start of the main perennial Poa seedhead flush at anywhere between 130 and 150GDD (in total starting on Jan 1 using a 6°C base) So my hunch is that we are a long way from an early Poa annua seedhead flush if you work on GDD.
Poa annua and rooting….
I left some of the cores I took from a green last Wednesday in a plastic bag and went to look at them today. Not surprisingly the shoots were elongated a tad due to a lack of light, but I was amazed at the amount of root development. Look at this picture from one Poa plant and it shows it has developed 2cm of root in little under 4 days !
So that raises a number of issues in my mind. The first is why are the cores all showing healthy root development ?
Well I think this is down to mild (notice not warm as it is my house and I’m notoriously frugal with my heating don’t you know) indoor temperatures, lots of oxygen in the rootzone and the cores have dried out (but not to a point where the plant is desiccated)
I see a lot of turf areas with shallow roots and there are for sure many contributing factors why this is the case but key with Poa. and perhaps other plants is availability of oxygen and managing soil moisture levels proficiently. Easier said than done on a golf course or football pitch which is unprotected from rainfall. (unless you have a roof of course :))
It makes such a good case for aeration doesn’t it ? – i.e – Introducing oxygen into the rootzone and allowing water to move through efficiently.
It makes a good case as well for surface organic matter removal / dilution for exactly the same reasons and for sure if you have an accumulation of organic matter in the surface and / or it is insufficiently diluted with sand, then the grass plant will not be able to develop roots any deeper than this surface fibre layer. It doesn’t matter what you apply, you are not going to change simple soil physics and plant biology.
Ok lots of information to digest there and my head is spinning, so that’s it for another week…
All the best and thanks to everyone for their contributions in terms of GDD information, it really helps me put together this blog and I think it shows everyone why it is necessary to know where you are on your site.
All the best.