It’s very definitely autumn and what a quick transition this year with the leaves almost starting to turn on a light switch, one minute we were mid-20’s and in summer, the next we are having our first grass frost here in The Midlands and for some parts of the south as well.
I love autumn with all of its colours and smells, it’s a cracking time of year unless of course you have lots of leaves on your golf course or sports facility and you spend a life blowing them off and collecting them 🙁
It’ll be a short blog this week because I’m up against it time-wise so please bear with me if I start the weather week from Tuesday morning. No great shakes because aside from a heavy rain front that’s nudging the west coast of Ireland today, everywhere else is dry and some of us are having a lovely autumnal day….
General Weather Situation
So starting from Tuesday morning and we see that heavy rain front slowly edging eastwards across Ireland and because it is slow-moving it means it’ll give some very heavy rain in some parts of the west of Ireland. Moving eastwards to the U.K and we have a dull start to the day with more cloud cover so a much milder start than Monday morning when I had to scrape the frost off my car at 5.30 a.m. (Yes Angus sometimes I do get up earlier than even you 🙂 ).
As we progress through the morning that cloud cover breaks from the east coast to present another fine autumn day and that band of rain over the west of Ireland decides it’s not welcome and moves off west to leave behind a reasonable second part of the day there as well. So we see average temperatures for this time of year, mid to high teens, particularly in the south of England, it will be the warmest day of the week with a moderate south easterly wind.
Moving swiftly onto Wednesday and we see another fine dry day, a cooler start because of the lack of cloud cover on the preceding evening but most places enjoying unbroken sunshine, again starting from the east coast and moving inland. As hinted above, it’ll be a little cooler on Wednesday due to a brisker south easterly wind taking the edge off the temperature.
A similar picture for Thursday with perhaps more in the way of cloud cover for the east coast this time as a bit of Haar blows in off The North Sea. Otherwise fine, dry and dandy with temperatures reaching the mid-teens again for most areas, maybe a little lower if you’re under that cloud cover. The wind will sit in the east and will slacken off a little from the previous day but we will see the highest temperatures across the west of the U.K, with Scotland and Ireland low teens, typical of this time of year.
Closing off the week we see more North Sea Haar make an appearance on Friday pushing a belt of thick, but narrow cloud over the country. This may be heavy enough in places to give a spot of drizzle or fine rain. East and west of this, we’ll see some breaks in the cloud cover and some sunshine so all is not lost. As is often the case when we have an easterly wind in situ, the warmest, mildest regions are to the west, so mid to high-teens for the south west of England and Wales maybe and 2-3°C cooler than that inland and on the east coast.
Onto the all-important weekend and a similar picture for Saturday with cloud blowing in off The North Sea, so staying cool especially on eastern coasts and again inland that cloud may be heavy enough for some drizzle / light rain here and there. With an easterly wind in charge, even a light one, it’ll mean cooler and dull for the weekend with temperatures just nudging the teens, but it will be dry with the best chance of any sunny breaks across the west.
With Unisys Weather not quite back up to working order with it’s 10-day forecast only making it to 6 days currently :(, we’re going to have to rely on Netweather’s 10-day GFS prediction. Incidentally have you ever tried to get in touch with a large American company to ask them what’s going on ?….my advice, talk to your hand because it’s just as effective :(.
So next week at this stage is looking fine and settled with high pressure dominating, but there’s a potential fly in the ointment that I’ll highlight as a potential caveat 🙂
It comes in the form of a sneaky Bay of Biscay low pressure set to form mid-week, next week and it’s going to be a battle between this weather system and a continental high pressure to see which one holds sway towards the end of next week. So calm, dry, misty, maybe even foggy and sometimes dull because of that prevailing south easterly / easterly wind direction which will dictate cloud cover and hence night time and day time temperatures. The wind will pick up I think towards the end of next week as these two systems butt up against each other and time (and next week’s blog) will comment on the outcome.
It’s the first blog of the month so automatically Wendy launches into action and has produced her usual output for the Thame location 🙂
So what does GDD tell us for September from this location ?
Well with a recorded monthly total of 318.5, it was the warmest September we’ve recorded by some margin since we started collating data in 2010. We will look more closely at the GDD and Growth Potential information a little later in this blog.
Here’s some data from Irish locations and you can see they also enjoyed a pretty reasonable September with not quite the temperatures we did over here but still nice all the same…
You can see why September would be a great aeration month because it still carries good soil and air temperature and interestingly the relationship between August and September holds despite the different locations across the U.K and Ireland. That is to say on average September is approximately 15% cooler than August so we still have good recuperative potential if we’re aerating. I say ‘if’ because September is nowadays one of the busiest months in the calendars for golf courses and so quite rightly most will not entertain aeration work and potential revenue disruption in this month. I say quite rightly because after all it’s the last big revenue input before the autumn / winter with October more of a weather lottery than September.
September 2016 – A tricky month to manage grass….
I think September 2016 wasn’t exactly a straight-forward month to manage grass because we had two distinctly different types of weather and as usual they brought baggage in the form of disease and plant stress.
The first type of weather combination was warm nights and high humidity, which meant the plant leaf stayed wet for prolonged periods. Anyone who has followed this blog will know that this combination of humidity, temperature and leaf wetness is a key driver for disease and specifically Microdochium (old man’s Fusarium), Dollar Spot, Red Thread, Superficial Fairy RIng and to a certain extent, Anthracnose Foliar Blight. You can clearly see on the graph when we experienced this combination of climatic conditions during September.
So we had high disease pressure in September and not only on golf courses but on sports pitches where Red Thread and Leaf Spot were abundant.
We also had a fair degree of plant stress and as we know this is a key driver for one of the most damaging turfgrass diseases – Anthracnose Foliar Blight. Again we can see why this disease continued to present a problem in September 2016, a repeat incidentally of September 2014 in this respect with high day time air temperatures and high evapotranspiration as well.
There were a number of periods when we had high daytime temperatures and high E.T loss from the sward so ordinarily we’d want to irrigate to replace the moisture that has been lost from the rootzone and therefore reduce plant stress. The reason I think life was made trickier in September this year was because this period came straight after or before periods when the leaf was wet and night’s were mild. So we went from no irrigation required to irrigation required and back again in short succession.
It was also warm but we sometimes didn’t need to irrigate….
Talking of irrigation, at the end of September (29th Sept actually) we also had some high day time temperatures but low E.T because we were humid and that meant although it felt warm we didn’t need to irrigate because the plant was not losing moisture to the atmosphere because it was already close to being saturated. Another tricky one to manage and this brings me onto an areas we have talked about before, irrigation…Now I appreciate it is a strange topic to discuss going into October but hopefully it’s food for thought for next year…
Most people irrigate in minutes of run time and that means diddly squat when it comes to replacing the correct amount of moisture in the rootzone. If you’re fortunate to have a weather station then you can use your E.T readings to give you a bearing on how much water is required by irrigation.
If you don’t have one, you can use the estimated daily / weekly E.T on Meteoturf (for example) for your location. So if we look at this week coming up, we can see that E.T loss is low (5mm for the whole week compared to 30mm in a hot, dry week) so even though it’s dry, there’s precious need to irrigate. (Not surprising really as it is October)
So how much to use ?
Typically I start on a 50% replacement of daily E.T basis, so if we’ve had a 4mm E.T day and the rootzone has dried out, I’d look to replace 2mm of that moisture using the irrigation system and then hand water ridges and any dry spots. Any higher than that and you end up with over-watered surfaces or parts of surfaces.
Now I accept a lot of people in this industry don’t have the budget for a weather station nor the time to sit and record stats, but honestly going forward this is one of the biggest areas of improvement of turf management. We have to know what’s going on with soil moisture and how much to replace or not to replace, we can’t just sit there and irrigate on run time regardless because that’s what we’ve always done.
Soil moisture levels drive disease, cutting height, plant stress, greens playability, thatch production, nutrition, pretty much everything we have to manage and yet we know so little about what we are doing in some cases. My suggestion is to look at purchasing a moisture meter so you can see how efficient (or inefficient for that matter) your irrigation system is. You can use one to change sprinkler run times accordingly, rotation from 360° to 180° (or vice-versa) and / or fit more efficient sprinklers if they’re required. (if coverage is poor for example). Yes, there’s an initial cost to this but you will save money in the long run I assure you, either by reduction of irrigation (because you actually need less than you think you need) or by drying out the rootzone you have less disease pressure (as one example).
9 out of 10 people I know that have brought a moisture meter are surprised how long they can actually go without needing to irrigate. My last words on irrigation for this year…”If you don’t measure, you can’t manage”
Ok off my extremely battered Soap Box and onto matters in hand…the next few weeks..
Disease pressure what else ?
Normally the first two weeks of October represent the start of the Microdochium nivale season in earnest but this year will be different I think. Many end-users have had to apply a preventative / curative fungicide early this autumn because of the higher disease pressure in September (for reasons I have already covered) but looking ahead our disease pressure will be lower than normal for this time of year because we’ll be dry (hopefully). That means you can potentially hold off the next application till we see moisture on the horizon in combination with mild night time temperatures (It’s this combination that drives the most aggressive disease outbreaks) and then apply. For the moment I’d just keep things ticking with light foliars and iron, maintaining plant health but not promoting lush growth nor leaving the plant hanging. (weak)
Ok that’s it for this week, a late one because I was elsewhere from early this morning and so I’m now playing catch up (Poor management of my own !)
Enjoy the autumn sunshine, kick a few leaves around and have a good week.