As I walked at the weekend on a beautiful Sunday which hit 23°C, I was struck by just how many fields were ploughed or being ploughed, cultivated and seeded ready for the arrival of the autumn rain and of course I wondered when it will arrive ? Hopefully not too soon for this maize crop which offered a surreal walkway spanned by huge individual plants. Here in The Midlands, we will have a September with no significant rainfall and monthly totals in the single figures no doubt.
It will change though because the jet stream shape and orientation is changing at the end of this week, see below….
Ordinarily a dry September should have presented a low disease pressure month, but not a bit of it with aggressive Anthracnose Foliar Blight, then Microdochium and last week I picked up the first reports of Dollar Spot on outfield areas (though it has been doing the rounds in Germany for awhile now as I’ll find out this week because I’m off on my travels again (ho hum) to Germany and Switzerland)
General Weather Situation
Ok onto this week and Monday looks a settled day after a very mild night (15°C) with hazy sunshine, though plenty of cloud cover. Later on around lunchtime, a group of showers will break out moving up the Severn Estuary towards the West Midlands. At the same time, another batch of showers will affect south-west Munster moving up the west coast to affect Shannon and south Galway later perhaps. Temperatures will be mid to high teens, perhaps higher in the south of England and the winds, light to moderate from the west.
Overnight these showers are set to fizzle out, but by early morning a new rain front reaches the west coast of Ireland and pushes eastwards in a vertical orientation. Clearing after the rain, by lunchtime this rain front will be into the east of Ireland and west coast of Scotland, progressing into the south-west of England, west Wales and north-west England by the evening, though amounts should be light. Temperatures will be similar to Monday.
By Wednesday, we see more showers moving across Ireland and pushing into the west coastline of the U.K through the day, but these struggle to move inland as they butt up against the continental high pressure, so further east and south it’s likely to stay dry, but with more cloud cover and temperatures still decent like
Thursday looks potentially the driest day of the week if you take the U.K and Ireland as a whole with hazy sunshine or longer spells of clearer weather. The key will be the wind direction because it should start to swing round to the south-west, heralding the arrival of the Atlantic low referred to above for the weekend.
By Friday a rain front is set to push into the north-west of Ireland and Scotland and move slowly south eastwards through the morning rush hour reaching the north of England by the evening. This rain will continue to move south through Friday night into Saturday potentially becoming heavy over The Midlands by early doors Saturday. So a wet start to the weekend for The Midlands and south, but drier and fresher further west and north with showers pushing in overnight into Sunday. Sunday looks cooler with more cloud cover and temperatures down to where you’d expect them to be for this time of year as that warmer air gets banished to the continent, so mid-teens the order of the day. There’s a chance of showers on Sunday further west and north and these may push into the southern part of the U.K later on Sunday.
So are we looking at a fundamental change in the weather or just a blip before we return to our Indian Summer ? Well we are certainly in for a change, how long it lasts is anyone’s guess but the image above shows how convoluted the path of the jet stream is and has been for a good while now (4-5 weeks). We’ve been sitting under a dry, warm peak, well it’s moving off and we’re going to get a trough in which an Atlantic low will deposit itself, so for me that means at least a week of unsettled weather and potentially heavy rain for some.
So the outlook for next week looks unsettled, right from the word go with cooler weather (but not cold) and rainfall throughout the week, pushed along on south-westerly winds. Some of that rainfall will be heavy and because the projection is that the low will sit south of Ireland, it means the whole country will get the rain.
Sometimes it must seem like I sound like a scratched record :(, but such has been the intensity of disease I can’t really talk about much else can I, particularly when you look at the fact it has been so dry, yet disease has been so aggressive, but why ?
Well the clue is temperature and humidity, without a doubt they are the drivers to the disease we’ve experienced, but the origin of that disease started way back in the dry, hot, stressy period of weather in July.
Last week we had some 15°C plus nights, but with lower humidity and therefore we got no dew formation, end result – little disease activity. Come later in the week and with the arrival of some dew, we get massive disease pressure, just like the weekend prior to it when Microdochium became extremely aggressive, especially on areas like tees and outfield areas.
I looked at some fairways last week that had been affected by both Dollar Spot and Microdochium, the distribution of the disease tied in with water movement, see below
I took some samples from the affected areas but I couldn’t see much mycelium under a low powered scope, so I incubated them in a plastic bag overnight to artificially increase the humidity, the effect can be seen below ;
So what have we learnt about disease activity ?, well it is very closely linked to humidity and temperature with plant leaf moisture being the key vector for disease movement at least for diseases like Dollar Spot and Microdochium. The Anthracnose Foliar Blight we saw kick off so aggressively in the early part of the month was is linked to the opposite, lack of moisture causing plant stress and then disease.
During this period and the one we’re just heading into, many of you will have or will be applying fungicides, but may question on occasion their efficacy, if you still see apparently active disease activity.
This is occurring because the rate at which the disease population is growing is faster than the rate at which the fungicide A.I is controlling it and suggests that the drivers to disease are playing a significant part. Now sometimes those drivers are out of your control i.e the weather, however you must pay attention to the drivers that are in your control, namely plant leaf moisture levels and organic matter.
It all starts with organic matter
Organic matter remains one of the biggest influencing factors to many disease outbreaks and spraying fungicides often hides the fact that if more organic matter control was carried, the disease pressure and hence reliance on fungicides would decrease (but not disappear) Now that I know is easier said than done, particularly on outfield turf, but it is worth remembering.
Organic matter holds more moisture than rootzone and so provides a key component / driver to disease activity in the shape of Microdochium and Dollar Spot (on outfield areas). It also dries out quickly, heating up faster than rootzone and becomes hydrophobic, putting the grass plant under stress and initiating stress-related pathogens like Anthracnose Foliar Blight.
It often amazes me talking to golf clubs who have a non-sympathetic attitude to aeration and topdressing “We don’t like the disruption and can’t afford to topdress much because of cost and more disruption, blardy, blah…..”, yet seemingly when they get hit with disease it’s no issue to ‘find’ the money for a fungicide application. (Roughly the same cost as one load of topdressing I think)
The reason is clear, the “If it ain’t broke, don’t fix it” attitude prevails in a lot of establishments when it comes to aeration and understanding why it’s required to maintain playing surfaces. In my mind it represents a clear lack of proactive management and targeting of resources. I think a lot of clubs simply cannot understand why this work is necessary when surfaces already look good, because it’s the preventative nature of the argument that is so difficult to communicate and grasp (IMHO)
When disease hits, it’s evident, real, in your face (and theirs) and so reactive management kicks in, “Of course you need to spray before we lose the greens, blardy, blah). The problem is with our ever-changing climate and the issues it brings with it, reactive disease management is for ‘La La Land’, it simply doesn’t work. We have to stop a high population of disease establishing in the first place, and that means a preventative strategy, full stop, end of discussion.
That preventative strategy involves ;
- Organic Matter measurement, benchmarking and control so you can make an argument for the need for aeration and monitor its efficacy.
- Aeration dates clearly laid out in the calendar, not pushed to the end of the fixture list
- Adequate topdressing to create a drier, free-draining surface environment
- A mix of grass species that lowers overall disease susceptibility
- Maximised plant health, avoiding elevated levels of plant stress
- Moisture monitoring to tie in with point 5.
- Preventative use of targetted fungicide applications
With all this in mind and looking ahead, we have a potential change in the weather on the way and this will bring moisture and higher wind speed, so the opportunity for spray applications will no doubt be less. So I’d be looking to get a preventative fungicide application on this week if you haven’t already done so (And most people have I think) for the control of Microdochium. I’d look to combine that application with a liquid iron (acidifying in nature the only prerequisite) in order to enhance efficacy. (Provided you know the are tank-mixable)
Moss it’s here again…
So after a dry July where we experienced sustained high temperatures, a wet and cool August and then a dry September, I’d suggest we’re going to see a good deal of moss this autumn once the rains arrive (though Silver Moss is showing already) because it can survive higher levels of dessication than the grass plant. So typically it’s going to appear on thinner areas which may have lost some density during the summer or on areas out of play which have accumulated more organic matter. For the latter if we’re talking golf greens, and if practically feasible, one of the best preventative applications is golfer’s feet, so if possible put the pin position more in the neglected areas. Now I appreciate that many times, it’s neglected for good reason, i.e the green has been designed in such a way that the pin and hence golfer’s feet aren’t going to head in this direction, but sometimes this isn’t the case.
Ok must dash, have to iron, pack and catch my flight to Germany via the obligatory Birmingham Airport Costa where a nice DeCaf Flat White beckons, but no RAB (Raspberry & Almond Bake) because I’m a tad too porky for my liking
All the best