140324_gfs_500p_loop_eur

Hi All,

As I type this I’m listening to the neighbour scraping ice off his windscreenShadePic (resplendent in his dressing gown I’d add!) That after a ‘four seasons in one day’ weekend with sunshine, rain, hail, flat calm and howling winds all in the mix. Took this pic of the shadow from my car on my lawn, you can see how shade effects temperature and hence frost formation / thawing.

Spring for nature though continues at a pace, my Hedgehogs came out of hibernation a month earlier than last year, (and they’re well hungry)  I reckon I can develop a GDD model for them ! The first Sand and House Martins were buzzing over Thornton and Ravensthorpe reservoirs over the weekend, filling up on hatching midges after their long trek up from Africa… so whatever you think / thought first thing this morning, Spring is well on the way !

The underlying weather patterns are also changing, bear in mind over the last 2 years we have seen a shift in the jet stream at the beginning of April that has set the tone for the Spring / Summer, I’m watching it intently. One thing that appears to be happening at the moment is that the very strong jet stream current that we’ve had since mid-December is weakening markedly and you can see that from the lack of movement on the Unisys plots, it’s a very strange mix of high and low pressures, haven’t seen anything like it before and it’s going to be difficult to intepret over the next week or so…

General Weather Situation

Ok, so Monday looks fine and frosty for a large swathe of the U.K, but a rain front is already into Kerry and pushing north-eastwards across Ireland. By early – mid afternoon this will be into south Leinster and the south-west of England and gradually it’ll push up north-east. Overnight it’ll fizzle out, with the heaviest rain tracking along the M4 corridor, but the east of the country will stay dry. Winds will be from the south, but later in the day they’ll swing round to the south east for Tuesday. Scotland should be dry to the wee hours of Tuesday when that rain flirts with the north-west coast overnight into Tuesday.

This change in wind direction stops the rain from moving across to the east coast, with any remaining rain sitting over the south / south-east corner of the U.K and the north of Ireland. As the wind changes to the south-east, it pushes the rain back the other way, westwards, over Ireland and down across the south-west of England during Tuesday evening, so a wet end to the day there. Away from this rain it will be bright and breezy, with light to moderate winds and temperatures in the high single figures. Another dry day for Scotland.

Moving into Wednesday we look to be dry for most of the U.K and Ireland, however later into the afternoon, a rain front is projected to move off the continent and into the east coast of England, so although you guys missed the rain in the early part of the week, you’ll likely get it on Wednesday. Away from this rain front, it looks to stay dry, cloudier than of late as it drifts in from The North Sea and feeling cooler too, as the wind swings round to the north / north-west, so pegging back temperatures. That rain will fall as wintry showers over the higher ground of the north-east of England overnight into Thursday and may push all the way across to Wales and the east coast of Scotland overnight, again falling as wintry showers.

By Thursday morning, those wintry showers are into the east coast of Leinster and falling as snow over the higher ground of Wicklow no doubt. That band of weak rain / wintry showers will hang over Wales, the west coast of England and the central Highlands, so feeling cold in that wind which has now swung round to the south-east.  As we go through the day those showers die out and a lot of areas will see the sun, lifting temperatures a little to close out the day.

By Friday we have two narrow bands of rain projected to affect north-east Scotland and the other the south Midlands, but I think the latter could pop up anywhere in the south to be honest. As we go through the day, those showers are pushed out to sea by a south-east wind, but there’s still a chance of rain affecting the south-west, Bristol / Bath area and the north-west of Scotland as well. Temperatures will feel milder than of late, hitting low double figures as warmer air is pushed up from the south-east.

The weekend is looking ok ish, with Saturday at present the best looking day of the weekend as the wind swings round to the south, picking up the temperatures markedly in the south of the U.K, possibly to mid-double figures. For Ireland a rain band is expected into Munster by lunchtime Saturday and this may affect Connacht and Leinster through Saturday afternoon / evening. Sunday looks potentially wet along the west coast of England and Wales, though this may spread further east and cloudier elsewhere, with more cloud everywhere pegging back temperatures a little over Saturday. Winds will be moderate and from the south, dropping down as we go through the day. By late afternoon, that could cover may break to give a nice spell of sunshine over central areas.

Weather Outlook

As commented on earlier, the weather is a bit mixed up at the moment, however I’ll take a punt at it. W/C 24th March looks to start resonably well after the easterly winds that’ll dominate the end of this week are set to swing round over the course of next weekend and push in from the south. This shift in wind signals the arrival of an Atlantic low pressure system that brings milder air and rain to the west for the start of next week and by Tuesday some of this rain may be heavy over the U.K. This wet period will extend into Wednesday accompanied by some strong westerly winds, so mild temperatures are predicted. The remainder of the week looks to stay unsettled with the winds shifting round to the north-west at the end of the week, cooling things down a little. It will mean good growing weather though because with the cloud cover, we’ll lose some low night temperatures and that’ll allow some good daily GDD figures.

Agronomic Notes

Speaking of Growth-Degree Days, how are we looking for March so far in terms of the growth potential of the grass plant ?

GDDMar12320141312

From the chart above you can see that the growth pattern for March 2014 and March 2012 are similar and what’s more distinctly different (thank god) from March 2013, when nothing was actually happening due to the prolonged cold spell. Comparing March from 2014 and 2012 shows that up until yesterday we are ahead in growth terms (23rd March), with 38.0 total GDD in 2012 and 47 total GDD in 2014. As you can see the figure for 2013 was 12.5. With the cooler daytime temperatures expected this week, I don’t see us adding much to the total above, not least till Friday when temperatures begin to pick up again.

…………………………………………………….

If we add up GDD to date, that puts us on 102.5 total GDD for the year to date 23rd March, we didn’t reach that total in 2013, till the 24th of April, so that suggests we’re 4 weeks ahead of last year from a growth potential perspective and 7 days ahead of 2012. Of course a lot will depend on what Mother Nature serves up for April, but if we carry on tracking like this, I’d say we’ll see the Poa Seedhead Flush at the end of April over here in the U.K and earlier usually in Ireland.

I say usually because currently the east coast of Ireland is tracking a good way down on the figures above from The Oxfordshire with total GDD’s up until yesterday varying between 45 (Cork), 65 (Wexford) and 50 for The Midlands. Over on the west coast, the figures are naturally higher (115 down on the tip of Co. Kerry). It will be interesting to see if the Poa does indeed seed earlier this year with these GDD’s….because in theory it should be later than central U.K for the east coast of Ireland and earlier by a week or so on the west.

Grubs

There are an awful lot of Leatherjackets around currently, varying from small, Bibionid-size, right up to much larger larvae. If you are coring, aerating, vertidraining, etc make sure that you do a test plot to see if the area needs treatment beforehand because I saw a lot of countersunk patterns around old vertidrain holes last week indicating their presence. I guess the milder winter has meant much higher survival and more larvae closer to the surface…The same goes for Chafers…If you note an area that isn’t responding to nutrient applications, rainfall, aeration, etc particularly on outfield areas like fairways, winter sports pitches, do a test spray plot or put down a Hessian sack overnight to see if anything emerges.

Application Timing

With milder weather at the end of the week and rain expected in the early / mid part of next week, now is a good time to get your soil surfactant down and if you’ve noted grub activity, why not combine it with a Chlorpyrifos application (provided the products are tankmix compatible that is) to ensure that it is mixed into the soil layer uniformly.

Depending on what you’re trying to achieve nutritionally, the end of this week is a good time to fertiliser with a granular fertiliser, equally if you’re using liquids you should get good uptake on Friday prior to a warm (ish) weekend.

Poa – It’s one diverse species !

I took three little plugs from a golf green of similar looking Poa annua early on this year and transplanted them into a pot with a nice rootzone mix and then let them grow on (and up). The plugs looked pretty much identical when mowed at greens height, but look how different they are when they’re allowed to grow upwards. You can see tight, bunch type growth habits along with elongated, paler plants as well.

Poa

It’s no wonder that when we get to this time of year and we see mottling on the surface following aeration / fertility or both, when you have distinctly different Poa plants from a morphological perspective…These grow differently, uptake nutrients differently and have different leaf colours to boot !

Ok that’s it for this week, sorry it’s a bit late in the day, but you know the reason  (It’s that bloody full intray again)

All the best…

Mark Hunt