Well what a weather week that was, temperatures touching 32°C in sunny Gravesend (hope your tan is coming on Lee 🙂 ) and then that break down which actually started on Thursday night, as thunderstorms came up from The Bay of Biscay into south-west England and moved up country. I was fishing on Saturday at Thornton reservoir and saw the storm approaching over the village, I thought it was going to pass by, but 10 minutes later all hell broke lose. Sitting in a boat on a reservoir with a carbon fly rod isn’t the most sensible thing to do, so I beached the boat and sat in a copse getting thoroughly soaked and crossing everything when the lightning came close… nice.
I’ve put together a series of graphics from NetWeather’s lightning archive which shows the track of the storms starting on Thursday and finishing with the flooding over the east side of the country on Sunday night when Canvay Island got clattered (no jokes please!)
Apart from the lightning and rain, we can expect a nice nitrogen input from all those storms as nitrogen dioxide in the atmosphere is oxidised to nitrate nitrogen by lightning and this then falls in the rain as a dilute liquid feed, hence the reason turf always greens up after a thunderstorm. I took 2 samples from Friday’s rainstorms as they were falling, (cue neighbours curtains twitching) so I’ll let you know how much nitrogen they contained in next weeks blog.
So how is this weeks weather shaping up?
General Weather Situation
Well, it’s going to be a lot quieter and drier this week, except for Ireland which may pick up some rain courtesy of an Atlantic front. We’ll also have some cooler nights of late, so in the low to mid-teens, instead of 20°C plus, which should make sleeping a better proposition 🙁 So Monday looks like starting off nice and dry with hazy sunshine for most, with the only fly in the ointment being rain over the south-west of Ireland which will creep slowly across country, dissipating as it does so…For the U.K it looks like being a very pleasant day, temperatures up in the low twenties and a gentle north-west wind. At the back end of the day, there’s just a chance of some continental rain drifting across The Channel to affect the far south-east of England.
For Tuesday we have a similar picture, but with less cloud cover, temperatures will pick up to low-mid twenties and it looks like being a lovely day. For Ireland again we have a rain front moving up the west coast during the morning but this time it looks to just track up the west of Munster and Connacht rather than moving inland. The wind will also move round to the east later on Tuesday.
For mid-week we have an identical day to Tuesday, warm, dry and bright across the entire U.K and with just the chance of a rain front skirting along the west coast of Ireland through the day.
Thursday again looks similar initially, but there is more chance of catching a shower particularly across Ireland as that rain front looks to extend across the whole country during Thursday. By the afternoon there’s also the chance of some rain showers pushing up from the continent into the south-east / west of England and into Wales. The rest of the country should stay bright, dry and warm with similar temperatures to Tuesday and Wednesday.
Closing the week out we have a subtle change in the weather as low pressure begins to introduce some moisture into the equation, it’ll still be nice weather, but we’ll have a higher risk of some light rain moving over from the continent for Friday particlarly for the afternoon. So potentially some rainfall (though light I think) for the east coast of Ireland during the afternoon / evening and also for the south-east / east of England tracking westwards through the afternoon. These showers hould become isolated by the evening though. Temperature’s will be a little lower, (low twenties) for the end of the week as that wind swings round to the north east.
So how’s the weekend looking ?
More of the same really with a higher potential for rain over the north-west of Ireland and Scotland on Saturday, plus the risk of some isolated showers over the U.K during the day. Temperatures will still be low twenties, perhaps a tad higher, but sunny between those isolated showers. The same is true for Sunday, a mix of sunshine and showers, more prevalent in the north-west of the U.K and Ireland, but pleasantly warm during the day. Winds will be from the north-west.
As predicted, last week’s warm, hot, humid weather turned up some of our more exotic diseases, with an abundance of Fairy Rings and Superficial Fairy Ring to boot. One disease that made an appearance on a number of courses was Waitea Patch. (Pronounced “Wait-here”)
Closely resembling Superficial Fairy Ring (SFR), this disease is actually a Rhizoctonia sp. and tends to pop up at pretty much the same time as well. It’s tricky to tell the difference between the two diseases, certainly Waitea doesn’t have as strong a musty smell, nor can you see the cottony white mycelium as I discussed last week with SFR.
Waitea Patch loves moisture so it typically occurs on wetter greens, those in the shade are a favourite. Hand watering will actually make it even more pronounced, so that’s why it’s important to know the difference because if you treat it like SFR, you’ll only make things worse. Normally it doesn’t take turf out totally (Unless you know different Kate ?) , but does look unattractive because it’s bright yellow, however as conditions change (temperature and humidity lower and areas are dried out) it will tend to fade into the background, often re-occurring again with rainfall and / or irrigation. The most effective treatment is Azoxystrobin applied in a good water volume (600L / Ha) and accompanied by a couple of passes of irrigation to just push it off the leaf into the surface, rather than drenching it through.
Fairy Ring Update
Last week I showed you an image of Type 2 Fairy Ring with the different moisture %, within, on the edge and outside of the patch:
As I commented, the inside of the Type 1 Fairy Ring was hydrophobic (water repellent) and consequently showing low moisture levels to the point of stressing the turf.
The areas were then treated with a wetting agent tablet and hand-watered (along with some rainfall). As of Friday, the moisture levels have increased to around 10% within the patch and the turf is recovering.
It begs the question when we look at Fairy Ring management whether we should bother with application of a fungicide ? In my mind we are dealing with the symptom, not the cause, by doing so, i.e Fairy Rings tend to occur where there is surplus organic matter, often in areas away from the pattern of play (on a golf green this would mean away from traffic paths and pin positions), so unless this is dealt with by aeration, we will just see the same pattern occurring year after year. (requiring the same fungicide treatment)
Now before you all comment that you have Fairy Rings, but no fibre, I accept that it’s perfectly normal to sometimes see them where fibre levels are under control. In this case, simple pressing down on the affected areas will show no dishing and therefore no disruption of the playing surface. So a bit of hand-watering, wetting agent usage will clear it up no problem. My concern is where fibre is excessive just treating with a fungicide is dealing with the symptom not the cause.
Plant Pathogenic Nematodes (PPN)
Plenty of activity around from these little buggers at present because being Poikilotherms (Organisms that are unable to regulate their internal temperature), the warmth through this spring and summer to date is boosting their activity. Now I know we have a very good support system in place for dealing with PPN’s, but it’s worth noting that if you have an analysis done and it identifes a number of species, it won’t always highlight which of the PPN’s present is causing the actual turf symptoms, so here’s a few images and notes to help you on the way…
Symptom – Loss of Poa in sward, ingression by bentgrass species, can resemble thatch fungus, but doesn’t have musty smell or localised hydrophobicity,
Likely Cause – Endoparasitic species probably Sub Anguina, Heterodera
Symptom – Yellowing of sward in irregular patches, can be complete circles, but more often irregular, horse shoe shaped, During July-September may result in turf loss where very high localised PPN populations are present.
Likely Cause – Ectoparasitic species probably Spiral, Stunt, Sheath species (or all three)
One of the single-most important points to take on board when dealing with PPN’s is that there is usually a contributing factor present that weakens the plant and thereby causes expression of the symptoms. It’s also fair to say that removing this contributory factor (rather than the nematodes) often results in turf recovery.
It’s quite possible for a healthy grass plant to withstand the presence of a PPN, but when the plant goes under stress, sometimes it cannot cope with the combination of PPN and stress and begins to suffer.
Types of stress that I have seen cause issues are ;
- Inadequate aeration results in poor root system due to thatch, compact fibre, bridged rooting and renders plant more vunerable to damage by a PPN.
- Over-use of PGR (rate) causes Poa to weaken and reduces growth rate.
- Excessive N fertilisation produces poor root system as plant puts its efforts into leaf and shoot growth at the expense of root development.
- Inadequate N fertilisation produces a weak plant unable to produce enough leaf, shoot and root growth to ‘grow away’ from effect of pathogen.
- Tornament conditions – use of grooved rollers, low cutting heights, frequent cutting, etc applies increased stress on the grass plant.
- High sustained temperatures applies E.T stress to the plant and damaged root system is unable to provide necessary moisture ot the plant.
I’m sure most areas of turf have PPN populations, the rub is that they only become an issue when management or the environment (or both) applies a stress to the grass plant.
If you don’t agree with the contributing plant stress theory, explain the picture below that shows Spiral nematode patches in the three lines caused by driving a triple over a green during high temperatures when the plant was at wilt point…
Ok that’s all for now, back to the grind. Enjoy the week…