Whoops – It’s July already! Really it is, how time flies! Firstly an apology, I like to think my forecasts are reasonably accurate, but last Friday’s was plain wrong… The rain moved in from the continent and extended further south, so pretty much everyone got a drop of rain, on the flip-side, the weekend was spot on lovely 🙂
Mock the jet stream at your peril – Reading last week’s New Scientist, I was amused to see it’s not just me that gets caught out by the weather, but at least I understand why :). Sarah Palin, prominent American politician, poured scorn on Global Warming recently when Alaska suffered a record cold snap, quipping “Global Warming, my gluteus maximus!”, which apparently means “my backside”. Shortly after, the jet stream duly threw up one of its peaks over Alaska and they recorded record high temperatures of 36°C! Read the article here and a separate meteorological report here.
Coming our way soon – our own mini summer jet stream peak ! – Some of you may have attended one of my recent talks, where I highlight the peak and trough nature of the jet stream, focusing on the trough events of winter 2010 and the summer of 2012. I also mention that we’ve yet to experience a summer peak i.e. where hot air is pushed up from the continent… Well I think there’s one on the way for next week, not sure how long it’s going to last for, but I expect it to be extremely hot while it’s here…
General Weather Situation
A cooler day than yesterday with more cloud, as a weak low pressure system pushes in from the west and brings rain to west Scotland during the morning, slipping south to affect the north of England and maybe the Midlands later in the afternoon in the form of showers. Temperatures will be high teens over the south of the U.K and winds breezy from the west. By Tuesday morning, a rain front is pushing into west Munster, Connacht and making its way eastwards, so a wet start for Ireland. That rain will reach western coasts of the U.K by mid-morning and mainly affect Scotland, Wales and the north of England during the afternoon, but later on there’s a chance of it pushing further south to affect more southern areas going into the evening.
Wednesday starts dull and still a little wet, with some light rain persisting over Ireland, Scotland and the north-west coast of the U.K. Further south it’ll be dull early doors, but the sun will push through to give hazy sunshine and temperatures will pick up a little, to high teens, on a north-west wind. Thursday is a carbon-copy of Tuesday, with another rain front pushing in to the west of Ireland early doors and moving eastwards through the morning to affect Scotland, the north of England and Wales. Further south, it should be mainly dry, with hazy sunshine and temperatures lifting into the low twenties as that peak slowly pushes up from the continent. By Friday, that rain is still lingering over north-west Scotland, but for Ireland and the U.K. it’ll be a warm day, with hazy sunshine and temperatures in their low twenties, so a really nice end to the week.
The forecast for the weekend looks very good, especially for Sunday when the first real heat from that peak is projected to reach us. You’ll notice because the wind will drop and that heralds the arrival of the warm weather. There’ll be a smidgen of rain affecting north-west Connacht, but everywhere else it’ll be dry.
As mentioned above, I expect next week to herald the arrival of a heatwave, courtesy of a summer peak in the jet stream. How long it will stay for is anyone’s guess? But certainly the early part of next week looks very warm, possibly cooling a little as we go through the week (but with temperatures still in the low twenties), before building again at the end of the week. Of course high temperatures can spark off thunderstorms, but we’re too far away to forecast these, so a dry outlook appears to be on the cards for most, with only Scotland / north-west Ireland possibly looking to receive some rain over this period.
It’s no surprise when you see a readout like this on the weather station, that disease has been very active over the last week. High temperatures, with rainfall and humidity are a breeding ground for fungal development with Fusarium, Red Thread and Superficial Fairy Rings being the most active of all the pathogens. It wouldn’t surprise me if there’s also some Waitea Patch doing the rounds as well, as it does like humidity and temperature.
Superficial Fairy Rings can occur in lots of shapes and sizes, from yellow vague rings (sometimes mis-diagnosed as Waitea I think) to the dark green sunken patches of Thatch Fungus. It’s worth noting that you can also see this disease where you don’t have a thatch issue per say, but usually it indicates excess fibre is present. It’s also worth noting where the disease is occurring on a green, because sometimes (not always) it can occur on an area where the pin in seldom placed (usually due to the design of the green), so foot traffic is less and fibre accumulation more. By the same mechanism, a tournament tee that receives little play builds fibre. This can then highlight the need for extra aeration on that particular area of the green, i.e double coring when the rest of the green gets one pass.
Treatment can be a little frustrating as we really only have the Strobilurins to work with (with Azoxystrobin seemingly the best of the bunch due to its mode of action) and in my experience, preventative applications are more effective than curatives. As mentioned on previous occasions, finding the depth of the fungal activity is key to treatment and to achieve this, I always suggest a droplet test, as the picture shows here to identify the depth of the rootzone where the fungal pathogen is active. Always tankmix with a surfactant (provided it’s compatible and approved of course :)) and if the fungal activity is deep in the rootzone, it may pay to solid tine to a depth just above this, prior to application. I’m going to post a fact sheet in pdf form later in the week to provide more detail.
Thatch fungus is a harder one to deal with because it tends to occur more intensively across a green and if fibre is present, the dishing effect can disrupt play significantly. Aerating can also be tricky because if it’s widespread, then the surface can be prone to heaving, so watch your tine sizing and spacing if you intend to do this. Again Strobilurins are the main port of call in terms of chemical treatment, but the real issue is organic matter and this can only be effectively addressed by aeration.
Button things down
If the heat does arrive as forecast, for however long, it’s good to be fore-armed and fore-warned in my humble opinion. That means using PGR’s to slow growth, where practically feasible (and therefore slow down the plant’s water requirement) practicing so called Pre-Stress Conditioning. Using low, balanced nitrogen inputs, continuing last weeks suggestion of mainly liquid / foliar fertilisation and ideally tank-mixing in a biostimulant, preferably containing seaweed and humic acid to maximise antioxidant production prior to the heat. Backing off on intensive aeration, especially lateral work like using the Graden or a deep verticut and instead just light grooming / brushing and if necessary, alternate cutting with rolling, if the heat looks like staying around for a while.
It goes without saying that irrigation and hand-watering (around golf!) is a given, but actually it doesn’t look like the wind will be that strong during this mini heatwave, so E.T levels should be bearable. Different from yesterday (Sunday) when we had very strong winds and temperatures up to 27°C in the south of England. I bet the E.T. was over 4.0mm (anyone care to post their weekends E.T. rates ?) and that means areas are currently drying out very quickly, even those receiving irrigation and last Friday’s rain. This weeks slightly cooler temperatures should peg things back a little and allow you to get moisture levels stabilised before the weekend.
That’s all for now, enjoy the summer..