May Golf Diary 2021

Editorin Golf
Expected weather for this month:

You can now access a week by week forecast at the Agrovista Amenity Academy -

Key Tasks for May

During spring renovations, most courses will be looking to aerate the greens and get some new topdressing materials back into the surface to restore levels and maintain surface porosity.

Choice of aeration varies between solid tine and hollow tine spiking depending on your goals, with the aim of getting some air back into the soil profile. Vert-draining using solid tines to a good depth (preferably >8 inches) should help the roots to start chasing the moisture down the soil profile, providing the sward with a stronger root system, which is the foundation of plant growth success.

This will be followed by topdressing with a compatible rootzone material. Do not over-do the topdressing rates; you do not want to smother your sward. The type of sand used in topdressings is vitally important, and you should be aware that most sand sales in the UK are for other uses. The sports turf market is small in comparison, so be careful if you are offered cheap materials, as these can be finer, differ in shape, colour, lime content and be more interpacking than the sands specified for sports turf.

For golf courses, the dominant particle range in the sand should be medium sand (0.250mm to 0.5mm).

The amount of topdressing will vary dependant on your needs. However, in the spring you would be looking to spread between half to one and half tonnes of material per green (2 to 3mm of material per m2). Many Greenkeepers are now topdressing on a monthly basis, a little and often approach.

Feeding programmes should be determined by soil analysis. Obtaining nutrient levels for greens, tees and fairways will provide essential information that can be used to help choose the appropriate fertiliser product for your given turf surface. There are a wide range of fertiliser products now available and tailored to stimulate healthy grass growth - see Agronomy Section.

It is important that your mowing machines are serviced regularly and are set up accurately, ensuring that both the height of cut and blade sharpness are correct. Damaged blades affect sward quality.

Irrigation systems should have been tested and calibrated by now, there is a need to ensure that all sprinkler heads are working and delivering the appropriate amount of water to the turf. You should calibrate your sprinklers at least once a year to ensure the spray pattern and coverage is sufficient for your needs. This can be done by placing out a number of catch cans on your green and measuring the amount of water collected. You may be surprised to find how much your sprinklers are actually delivering. There may be a need to irrigate during spring renovation programmes, as air temperatures and daylight hours are getting longer, increasing the likelihood of the ground and surfaces drying out.

Once these spring renovations are completed, you can then get on with the daily routines of maintenance, albeit they are likely to be reined back somewhat because there is no play.

Mowing operations are generally in full swing, with frequencies varying from daily to weekly operations dependant on the growth of the grass and the standards set by the course managers.

Mowing heights may vary depending on local conditions, type of course, course expectations, sward type and mower type. The mowing heights are a guide, and will be subject to local weather conditions, but remember not to remove more than 1/3 of total grass height in each cut. The less stress that is placed on the grass at this vital time the better the results further on into the season.

* Greens - height should be maintained at around 4-6mm. 
* Tees - height should be maintained at around 10-15mm. 
* Fairways - height should be maintained at around 15-20mm. 
* Rough, semi rough grass areas - mow and tidy up these areas.

Ensure you clean your mowers after use (wash down or blow off ), ensure you apply some WD 40 or similar oil based lubricant on the cutting cylinder after washing down. Keeping them clean makes the job of checking cutting heights and maintaining the bottom blades easier.

Hole changing is not necessary at the moment; but once play is allowed again, this should be carried out regularly, at least three times per week as a general rule; however, frequency will be dependant on a number of factors - green size, greens construction, tournaments, amount of play and condition of the green. During any wet periods, it is likely the hole will wear more quickly, resulting in a crowning affect and surface wear. This wear is more apparent if the green has thatch problems. The hole will tend to wear quickly and form a depression, caused by the placement of the golfers' feet.

Other tasks:

Ponds, lakes and streams - Inspect all water features on course, cleaning out any unwanted debris and litter. Some clubs arrange for their ponds to be dredged to clean them out while at the same time recovering any stray golf balls.

Tee boxes, tee markers and competition markers should be inspected daily, cleaned and moved to new tee positions as required.

Regularly empty litter bins/tee boxes.

Mark out trolley areas, out of bound site areas, ground under repair (GUR) and range markings.

Estimate and order seed, loams and fertilisers, fuels and other consumables.

Well, after a month of us getting some normality back in our lives, I think everyone is thankful for being able to do a little bit more. It is undoubtably going to be a slow process as we all adjust to venturing a little further and getting to see those people we haven’t been able to for a long while.

Grounds managers up and down the country have been working tirelessly to provide exceptional facilities for all those back playing sport and have done an amazing job. The weather has been very challenging over the last 4-6 weeks, with low to freezing night-time temperatures which has effectively put a stop to any significant growth. April has been the frostiest on record, going back to when records began in 1960; which has meant that recovery from any winter wear or damage has been limited. This has pushed progress a bit further back for some in terms of where they predicted their surfaces would be heading into May. On top of this, it has also been one of the driest months on record with many locations experiencing as little as 1% of the average rainfall in April; further adding to the challenges of the grounds manager. However, as stated in last month’s diary, growth can’t be unrealistically manufactured, and it is advised to work with nature, where possible, rather than try to force growth.

The forecast for May looks encouraging as night-time temperatures appear more favourable and we will have hopefully seen the back of any frosts. This, alongside mid-teen day-time temperatures, with 22 days forecast at 15° or above, will help to start generating some consistent growth, which puts more control back into the hands of the turf manager. The month appears to have a majority of bright days with only a handful forecast with rain. Historically, May can be seen as the month when spring really starts to take shape. The peaks and troughs of temperatures experienced in previous months start to settle down and the grass plant makes the most of the warmer temperatures and longer days, resulting in an significant increase in growth.

Many will now be well into their programmed approach to plant nutrition for the year, with possibly two or three fertiliser applications already made. Given the recent weather challenges from the extremely low temperatures, many will also still be waiting to see much response from the latest application, depending when it was timed. Acknowledging the recent stress that the plant has been under from the extremely low amounts of rainfall we have had, or the stress from cold irrigation water, which has been applied out of necessity, it is important to plan to help mitigate or alleviate these stresses that the plant has been under. Undoubtedly, once growth gets fully up and running the undesirable annual meadow grass (Poa annua), which will make up many sward compositions across the country, will be responding with its survival strategy…seed.

The onset of seeding brings with it an undesirable impact on playing quality, performance and overall aesthetics. Although grooming can be deployed to physically remove the seed, in some instances, and depending on the surface you manage, this can provide the perfect seed bed for those seeds which don’t make the journey into the grass box and fall back into the sward. At the time of year when growth is consistent enough to provide even swards, after weeks of the grasses in mixed swards all growing at different rates, it is key to manage this to ensure even growth is achieved. An even sward increases playing quality of the surface being managed and, in line with this, plant growth regulators can be used to great effect to help regulate the flowering capacity of the Poa annua plant.

Prohexadione- calcium (Class A late gibberellin inhibitor) can be used at cool temperatures and is active when sprayed onto the plant, therefore its regulatory effect is fast acting. A key benefit of this active ingredient is that it regulates Poa annua closely aligned with the desirable perennial grasses in the sward. This restricts the ability of the Poa annua to pioneer the sward, by not giving it the advantage of being out of regulation whilst the perennial species are still being regulated.  Its effect on seed head development reduces the impact on presentation and performance.

Ensuring nutritional inputs are managed prudently this month will be a key factor in how quickly surface quality can be achieved. The stress inducing environment mentioned earlier, underpinned by existing fertiliser applications, means that growth can be rapid with a detrimental effect if it’s not monitored. Many will switch from granular applications to liquid products, which can be applied little and often to give a regular, balanced amount of nutrient inputs, which can help to mitigate stresses and provide even growth. The use of surfactants, where possible, will ensure that moisture is distributed evenly through the soil which, in turn, improves plant health via better rooting and nutrient uptake. Added into this can be the use of biostimulants, such as seaweed and amino acids, which again will mitigate any stresses present.

An increasing problem at varying points of the year is managing pest populations. There have been numerous reports of leatherjacket damage outside of the “typical” peak season. There is no registered chemical control for this pest to be applied at this time of year; however, if damage is significant, it may be worth considering a spring application of nematodes to try combat the problem. Steinernema feltiae can be used at soil temperatures above 8°C and Steinernema carpocapsae above 13°C, therefore it’s important to choose the right treatment for your site at this time of year. The emergency approval has just been granted for the use of Acelepryn on chafer grubs in 2021, and this will be available to purchase from May. Installation of pheromone traps allows you to monitor which species you have and to plan accordingly; it also means you can track the peak flight period to time your product application for best results.

It has been an incredibly challenging winter and pre-season, but finally, it looks like there is good growing weather to work with. Let’s hope so!

It is important that all machinery is in good condition and well maintained. Machinery downtime, due to lack of maintenance or poor set-up, can be costly. As the weather continues to improve, you will be all-out to keep your course in tip top condition.

Courses with their own workshop and mechanics will be at an advantage. Those without such luxuries need to be ahead of the game - all machinery should have been serviced and back in action by now.

Having a good wash down facility is an essentail tool for keeping equipment clean; it is a wise investment.

For all your training requirements, please contact our preferred training provider - Grounds Training.

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