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Hi All,

bearSo this is my last blog for a few weeks just prior to setting out for Alaska. I’m looking forward to experiencing a true wilderness with no phone network and no WIFI. That said, it is going to be slightly strange not having use of a smartphone for information, pulling up weather forecasts and the like, kind of like turning the clocks back.  I remarked to a friend recently that I wasn’t worried about bears because I’m a reasonable runner and I just need to out-run my colleagues rather than the bear itself but this nice photo dropped into my Inbox recently so I’m not so sure now…..:) My mum suggested that I take extra toothpaste because apparently Bears like toothpaste so when approached I simply splodge a couple of dollops of Colgate’s finest and make my escape. I think it’s more likely they’ll use it to clean their teeth afterwards 🙂

All things being well I hope to be back in blog land on August 3rd.

General Weather Situation

So after a dreary and drizzly Monday, how is the rest of the week looking ?

For Tuesday we have a band of rain moving across Ireland, currently it’s affecting an area from Kerry up to east Leinster but during the course of the morning it’ll move eastwards to clear the west of Ireland and affect the east coast. There’s also some rain across South Wales (there you are Debbie) and touching the south west. Further east and north we have a hazy, dull start with cloud cover and a gentle westerly breeze and in places the cloud will be thick enough to give some light rain / heavy drizzle. Through the morning this rain will push across Ireland and into South Wales and the north west of England, but it will be light and drizzly by the time it reaches here. Through the afternoon the rain will move eastwards to the north east of England, but further south there’s a chance of the cloud breaking to leave a lovely evening for me to do my last minute packing !! Temperatures are likely to be high teens and low twenties if you happen to see the sun for any length of time, so nice and pleasant.

Onto Wednesday and overnight we have a band of rain pushing into the south west and Wales and this rain will move across England in the early hours. It’ll be light in intensity maybe 1-2mm but welcome for most I’m sure. By the morning rush hour that rain is likely to affect most of the U.K up to Newcastle, with intermittent lighter rain / drizzle over Munster and Leinster and a separate band of rain affecting north east Scotland. Through the morning this rain will clear Ireland, Scotland and the south of England leaving a band stretching across the north Midlands up to the north east of England. By late afternoon / early evening this will be confined to the latter. Temperatures will be similar to Tuesday, perhaps a degree or two higher in the south of England with those longer sun hours. Winds will again be light and from the west.

For Thursday we have a new band of rain, potentially heavy, pushing into south west Munster and looking likely to affect the west coast of Munster and Connacht through the morning, afternoon and into the evening. Further east over Ireland you should miss this. For the U.K it looks like a pretty dry picture for Thursday with cloud cover slowly breaking through the morning in places to give spells of hazy sunshine. Later in the day we have a threat of rain pushing into the south coast of England, with a chance of some heavier rain later over the south east of England, principally Kent. Warmer temperatures are likely with the low twenties forecast accompanied by a reversal in the wind direction, blowing off the continent from the east, but light in nature all the same. Now with temperatures rising and an easterly airflow there’s a risk of some thunderstorms breaking out on Thursday night into Friday morning along the east coast I think.

As we move into Friday that rain over the south east looks to intensify in nature and shift northwards into Essex, Suffolk and Norfolk, though this may well change as it’s continental rain and so fickle in its nature. That heavy band of rain affecting the west of Ireland may be slow to clear and as it does so on Friday morning it moves eastwards across the country. By morning rush hour that rain is into the north west of England and The Borders pushing up into Scotland on Friday morning. Through Friday morning and afternoon the rain slowly pushes north over Ireland so a bit of a soggy one there and for Scotland too. For the south of England and The Midlands that early cloud cover and possible light rain will give way to longer spells of hazy sunshine and pleasant temperatures up into the low twenties again. Further north and west where you have rain it’ll be cooler, more like mid to high teens and a return to a moderate / blustery westerly wind.

So how is the forthcoming weekend looking ?

Well Saturday looks a pretty nice day for most, lots of sunshine around and with that we will have some pleasant temperatures but since we still have a low pressure close, they’ll only be high teens, low twenties maybe in the Costa Del SOE. Later on Saturday you’ll see some rain crossing Ireland and moving into the north west of England, south west of Scotland. Sunday looks a repeat of Saturday for many, dry on the whole except for a new band of rain that’s projected to push into Connacht and Donegal during the early morning on Sunday and this will move east into western Scotland by the afternoon / evening. So all in all not bad, nothing too hot temperature-wise and light to moderate winds from the west forecast for the south of England, but nearer that low pressure in the north and Scotland the isobars will be packed so potentially windier and cooler for you over the weekend.

Weather Outlook

With low pressure influencing this week we have a change on the way pretty much kicking in from the start of the week as high pressure is set to build. So next week looks like being drier and warmer, potentially hot as we approach mid-week in the south of England especially. Before you get too worried though remember that we still have a jet stream with southerly tendencies and this means that it is only a matter of time before a new Atlantic low pressure whisks over to nudge the high out of the way. Sure enough this is currently projected for the end of next week, Thursday onwards as a low pressure pushes in to bring wind and rain to the north and west, but this one may just sit low enough to bring rain to the south of England as well and a cooler northerly airflow over the weekend possibly. The combination of heat building during the week and moist air pushing in from the west suggest to me that it may be a thundery end to the week, next week with a high likelihood of electrical storms as the air masses meet.

Agronomic Notes

Pathogen Activity

With moisture coming in last week and over the weekend following a dry spell of weather we have a surge of pathogen activity specifically Fairy Ring and Waitea Patch, but also some Microdochium pressure.

Waitea

Just to re-visit the subject briefly. If you’re seeing rings of fungal activity that suggest they may be Superficial Fairy Ring or possible Waitea, there’s a number of steps you can take to ascertain which species of pathogen you are dealing with. I say species because Superficial Fairy Ring is a Basidiomycetes sp. and Waitea is a Rhizoctonia sp., so very different in their activity, but similar in terms of symptom expression.

The first thing to do is to take a small corer and take a profile in the ring itself. Lay the profile horizontally and take a small syringe / dropper and place drops of water from the bottom of the profile upwards, say every 5mm or so. Watch the behaviour of the drops. If they soak into the profile you know the rootzone is not hydrophobic, however if they bead up you can see that hydrophobicity is present and get an understanding of how deep this is in the profile. Typically Superficial Fairy Ring (SFR) is present in the surface organic matter, 10-20mm deep and so often when you do the droplet test you notice the drops behave as shown below.

HydrophobicFairyRingCore

So if you’ve taken a sample from a ring and notice surface hydrophobicity that suggests fungal activity, but it is not a definitive because organic matter itself can be naturally hydrophobic. So next you need to look for any signs of fungal activity and in the above photograph you can see white, cottony mycelium amongst the organic matter. If you have a Veho scope handy you can pick this out much easier at x100 / x200 magnification.

The picture below shows Basidiomycete mycelium coating a sand particles and the root system of a Poa plant.

Fairy Ring mycelium covering roots and sand particles

Next take a good smell, this is actually best done when you first remove the core and try and detect the familiar mushroom odour associated with Fairy Ring activity.

Lastly if you incubate the sample in a plastic bag, you know pop it in the airing cupboard for the Mrs to find at a later date because you’ve forgotten you put it there 🙂 you will sometimes see with Waitea, fungal mycelium growth in the turf surface as opposed to the rootzone.

So to summarise, you have 4 definite features that can help to differentiate between SFR (lazy because I keep typing Superficial wrong :))

  1. Presence of hydrophobicity (SFR)
  2. Presence of mycelium often cottony white (SFR if in rootzone)
  3. Mushroom odour from surface of core (SFR)
  4. Surface mycelium growth ( Waitea-only)

It matters with these two which one you actually have because the management is quite different.

Waitea tends to like moisture so if you’re seeing the rings on an area of turf that sits wetter, maybe in the shade or possibly an area that gets routinely over-watered from the irrigation system, then this may point the finger Waitea’s way. Drying out the rootzone is a good way of reducing the appearance of Waitea Patch without having to resort to a fungicidal treatment.

With SFR, the opposite is true of course because the activity of the fungus can make the rootzone naturally hydrophobic and so hand watering with a wetting agent tablet (to neutralise the hydrophobicity) is a good idea. You can also check to see if the tablet is actually doing its job by testing the area the next day or so and seeing if the area is still water-repellent or not. If it is, hand the tablets back to the rep and ask for your money back 🙂 (ha ha)

if you chose to go the fungicidal root then Azoxystrobin is usually effective against both pathogens, but of course you should be mixing with a wetting agent if you know you’re dealing with SFR. (Provided of course they are tank-mix compatible)

Other Pathogens

After last years high level of Anthracnose activity, some of you may be nervously looking at the grass sward to detect any early signs. I have noted some indication of basal yellowing of the grass plant lately however on examination there is no indication of any Acervuli – spore-producing structures on the healthy tissue. I have found some on dead and decaying plant tissue but this is normal as it is a saprophyte. I put some of this basal yellowing down to Spiral nematode activity rather than Anthracnose incidentally.

Taking on board that we first had temperatures high enough for spore germination of Anthracnose at the end of June, it is likely that the fungus has only recently started growing. We know that Anthracnose grows very slowly on the plant and according to the disease oracle – Kate Entwistle (No ‘h’ you know :)), it is also quite sensitive to damage during the early stages of development. It needs good levels of soil moisture and humidity so maybe this last week and the early part of next week will help it on its way.

I repeat that I’m only talking about the fungal mycelium stage of development and this is one you’d only see if you have a high-powered microscope and know what you’re looking for. The actual turf symptoms (Leaf-yellowing, basal rot, Acervuli on foliage and the crown of the plant) come later, roughly 4-5 weeks after the initial germination of the spore I think, but this timescale will depend on the environmental conditions. If they are not conducive to Anthracnose mycelium development, the disease symptoms may not actually appear at all.

That’s why it is important to apply a preventative fungicide (if you chose to go down this route) long before actual turf symptom expression.

It is also vitally important to maintain good levels of plant health during the next 6 weeks because a weak plant makes an ideal calling card for this and other plant pathogens. So if you’re chasing a super-low N figure I hope you have your ‘i’s dotted and your ‘t’s crossed and more importantly, know why you’re doing it in the first place.

Maintaining adequate nutrition is key to Anthracnose management, ‘little, but often’ is an extremely apt saying when it comes to this disease. Research conducted in the U.S has consistently shown that good levels of nutrition (sufficient and regularly-applied rather than excessive) are equally as effective as applying a fungicide when it comes to Anthracnose management. If you want a refresher course have a look at this very informative pdf on Anthracnose  here

Ok that’s it for this week, bit of a short one I know but needs must.

Catch you on the flip side.

Mark Hunt