What a contrast of days for the weekend, Saturday, bright and beautiful here and Sunday, cold and very wet, we’re up at 33mm and counting with the rain still coming down and I know for the south and south west where the rain reached first, they’re up to 45mm+. That low pressure that was predicted to bring rain yesterday, rather than declining is intensifying, so it’ll be a dominant part of this week’s weather for most areas with rain and strong winds for the first part of the week and a quieter end to it. Agronomically I believe the first application of preventative fungicide should be geared for the end of this week because there appears to be some warmer weather on the horizon. This comment relates to The Midlands south and doesn’t include Ireland, Scotland and the north of England where the weather has been significantly different. (wetter)
General Weather Situation
Currently we have a very heavy rain belt situated over the south of England, with a particularly heavy band pushing up the M5 corridor down in the south west. This rain will slowly move northwards over the course of the day and in places I’d expect 30-40mm or more. Here currently (13.01 p.m.) it’s nearly dark and raining very heavily.
The rain front is set to rotate over the U.K and push westwards into Ireland later on, bringing rain to Connacht and Leinster early doors Tuesday, before pushing southwards through the day into Munster. Tuesday sees that heavy rain pinned down over the north of England / Scotland in a line stretching from Birmingham north, so south of that, a much better day initially, but later on in the day, the rain pushes southwards and intensifies, so I expect heavy localised rain for the north-west Midlands and north of it (Manchester / Leeds area) a.m, pushing south into the south-west and home counties p.m. Wednesday sees that rain lingering west Leinster / Munster and down the west / south-west of the U.K. During the day, it consolidates and moves inland, so again p.m. could be wet for most areas. Winds will remain strong over Tuesday and Wednesday and primarily from the south-west, tending southerly. By Thursday, things are beginning to settle down as that low begins to lose its strength, so a much drier day in prospect for all areas of the U.K and Ireland with only a risk of showers in the south-west and south coast, but these will be later on in the day. Winds will lessen, but it’ll remain on the cool side. For Friday, we have a weak band of rain coming down from the north west, reaching Ireland and Scotland in the early hours and pushing south and eastwards. So after a dry start, we’ll have showers bubbling up later in the morning for Wales and the west of England, pushing inland later in the day. For the weekend, I think it’ll be a reversal of last week, with Saturday a day of sunshine and showers, but feeling milder in the south. By Sunday temperatures will be on the up, nothing barmy like, but nice all the same and that’s what I think may trigger aggressive Fusarium.
Next week looks to be a week of sunshine and showers with a milder south-westerly wind direction and the U.K and Ireland split into two halves, with warmer air in the south and cooler, wetter air in the north and Scotland. Moisture never looks far away, but it may be that the end of the week is wettest, with another low pressure on the horizon. Temperature-wise, I would expect high teens in the south at least and that’s what will kick off the Fusarium after this weeks moisture.
The key area for me is timing of preventative fungicides with milder weather on the horizon and a saturated rootzone this week for many places. I appreciate many of you may have already applied a fungicide in early September (particularly Ireland where Fusarium starts 3-4 weeks earlier than in the U.K in general,in most, but not every year) to suppress disease active earlier in the month.
Many of those applications would have been for Fusarium, but also Anthracnose Foliar Blight (more on this later), so if you’ve already applied Azoxystrobin for example, don’t fall into the trap that you’re covered for Fusarium because that chemistry isn’t the strongest on this disease, despite what the marketing blurb we read says…For preventative applications on this disease, the research and end-user feedback strongly suggests a chemistry from the DMI family is most effective, so that’s Propiconazole, Tebuconazole, Prochloraz..
Looking at the weather forecast I think the application window should be Thursday or Friday for a preventative fungicide and that then sets the first one in place for end September / early October. I’d then look to repeat no later than 5 weeks after this first application, so that’s the 1st week of November.
By following this frequency, you’ll span the next 10 or so weeks, which always represent the maximum Fusarium pressure on our calendar. By keeping disease populations to a minimum during this period, experience and trial results show that you siginficantly decrease the risk of aggressive winter Fusarium during December, January and February. On the right of this page, under Turfgrass Disease Information, you can read a more comprehensive explanation of the theory and the trial results that support both the fungicidal and non-fungicidal approach to disease management by Headland Amenity.
Earlier, I mentioned Anthracnose Foliar Blight which has been doing the rounds now for the last month, not just in the U.K, but also on the continent where I visited Germany and Austria last week. This disease is a tricky one because it tends to come in quite fast (unlike the basal rot form which is slower) and particularly on areas of grass under stress.
Applications of fungicide (Strobilurin, DMI’s) are very effective, but the problem is that they often don’t appear to be, because the affected leaves still continue to die off and any recovery thereafter is wholely dependent on the ability of the plant to generate a new root system to support new growth. If conditions (local and environmental) are not conducive to recovery i.e high levels of thatch or localised, compacted fibre and climatically adverse weather conditions (dry, warm, hot) then all you effectively achieve is to ring fence the disease with a fungicide application, but you don’t stop it from taking out the grass plant, so the result is still pronounced die-back. (see below)
If you have this disease I’d work on maximising new root development by Sarrell Rolling, solid tining, top dressing to promote tillering into the weaker areas and maintaining adequate fertility. Overseeding poor areas is also an option and I’ve known greenkeepers to create a greens ‘divot mix’ with Fescue / Bent and rub it into patches (shown left) to increase grass populations. Running greens lean is a calling card for more disease, slower recovery and in essence the only grass you succeed in encouraging is the highly invasive, coarser, annual Poa annua. with is high seed production, i.e the less ‘desirable’ of the Poa species. (vs. Reptans of course)
Think that’s it for now, I thought I’d finish with a joke (unusual for me)….a man walks into a W.H.Smith and asks the assistant if they have the self-help book for men with inadequate tackle, “I don’t think it is in yet” she responds…”That’s the one” he replies….:)
All the best….