Report on visit to Dortmunder Golf Club by Peter A.Wisbey

2018-11-26 12:18 von Karin Burckhardt

        Report on visit to Dortmunder      

      Golf Club by Peter A.Wisbey of

         Practical Turf Management

                15th November 2018  


Herr Jürgen Brand                                                            Platzwart

Frau Sigrid Schenke                                                          Schatzmeisterin 

Herr Helge Paczenski                                                        Head Greenkeeper

Mr Peter A.Wisbey                                                            Course Consultant

2018 has been an exceptionally difficult year for those of us in the turf management business across Northern Europe. Firstly we had freezing temperatures well below normal, then a period of high rainfall; this was followed by one of the hottest summers on record, Helge informs me that temperatures rose to 38C. Now we are experiencing continued warm weather through mid November, the latter providing perfect conditions for turfgrass diseases. Any one of these would be challenging; but all in one year! Having said that your course has come through the year in good condition all things considered. 

First Impressions; 

As one should expect areas not covered by irrigation have suffered through the hot dry weather with the turf thinning as shallow rooted grasses, such as Poa Annua, have died out. The deeper rooted species simply go dormant, exhibiting a brown colour, and revive when moisture levels return following rainfall.

Most of the greenstaff’s time is presently taken up with leaf clearance. This is likely to continue through until the New Year.

Greens and tees which do receive artificial irrigation have remained green throughout the summer months and their condition will be covered in more detail below;


Dry patch has once again been an issue this summer with a number of putting surfaces being affected; most noticeably the 9th.

Greens 3 and 9 have had an aeration operation carried out by a contractor and a considerable amount of surface damage is noted. I am not familiar with this operation or what result it is expected to achieve? Normally contractors have a high level of expertise and little or no damage occurs if the equipment is correctly operated. Such significant damage must be very frustrating for Helge and his team who work hard to present these surfaces to a high standard.

Damage on green 3 will need to be repaired using turf from the nursery green. 

I was very pleased to note the very low incidence of the turfgrass disease; Dollar Spot (Sclerotinia Homoeocarpa) on the putting surfaces; in particular green 17 which has always been the worst affected. The 1st is probably the most affected at present however even this infection is minor. Daily dew (tau) removal and regular use of the turf iron (roller) have combined to reduce this disease.

There were some signs of Microdocium Patch on several greens; however these were restricted to parts of putting surfaces affected by shade such as the left hand side of green 10 and the rear half of green 5. These are minor and of little concern. With general regards to disease I am pleased to hear that fungicide applications have been minimal this year.

Deep air injection using the Air2 G2 is being carried out on a regular basis throughout the year; breaking deep compaction whilst having a minimal effect on the surfaces resulting in less disturbance to Members and guests. 

Deep slitting has already started and will now be ongoing.

Green speed was discussed, in particular the difference between the older and newer surfaces. In my experience this is down to the different grass species on the different surfaces.

Simply lowering the height of cut (HOC) is not the long term answer as cutting as low as 3mm as has been the case this season can cause damage to the grass plants which require a good sized leaf area to allow photosynthesis to  occur and healthy turf to be maintained throughout the year.

Greens 13, 14 and15 suffer from areas of Moss, particularly on high spots and slopes. This is a direct result of low HOC’s when the mowers bottom blade, or “bed-knife” scrapes the higher areas causing the turf to thin and become weak providing ideal conditions for moss to colonise.

This photograph is of the slope across gree 13; moss is light green in colour.  

We can work with Helge on a management plan to address the issues mentioned above.

I am pleased to report that the Clubhouse putting green as well as greens 2 and 4 are in the best condition that I have seen them.


  • Continue to slit all the putting surfaces and approaches as often as possible between now and April; weather and ground conditions allowing.
  • Apply Everris Autumn 6.5.10. +Fe fertiliser at 35grms / m2. Include approaches.
  • Consider putting 6” hole cups in the winter greens.
  • Repair damaged areas on greens 3 and 9.
  • Rest green 3 whenever possible by using the winter green.
  • Hollow core the high spots and slopes where moss is a problem on greens 13, 14 and 15. Roll afterwards.
  • Order in the soil / water management product Revolution and start to apply in early March 2019; repeat every four weeks. Correct timing is vital to the success of this product.
  • I have had great success with Revolution in controlling Dry Patch.
  • Raise the HOC to 5mm and maintain this until April 2019.


The approach areas are of great importance on a golf course as balls played onto them should release and run onto the putting surface. The HOC should be maintained at 10mm. Aeration, top-dressing and fertilisation should be the same as the putting surfaces.

The approaches with irrigation are in good condition; on those without it should be considered a priority that irrigation be installed. 


Grass cover is generally considered to be good. As the main playing areas have had a hard season it is recommended that play be moved onto the blue and orange areas for the winter months. Rope off tees such as the 1st, 3rd and 10th to prevent golfer traffic crossing them.

Aerate all tee tables with the Vertidrain fitted with 12mm tines.  


Firstly; of the fairways seen during this trip to the Dortmund area, yours are in the best condition in terms of grass cover. Even after such a difficult period in terms of weather the stronger grasses have revived.

We discussed the best methods to further improve grass density and coverage in the most cost effective ways. These include; irrigation, nutrition, over-seeding / grass type, aeration and top-dressing. 


  1. The use of self-propelled sprinklers could be considered however the following points are relevant;
  2. Water connection points will need to be installed along the sides of the fairways.
  3. Water pressure should be checked to see if it is sufficient to run one or more sprinklers. See notes on irrigation later in this report.
  4. Apply a slow-release fertiliser in spring.
  5. Apply a liquid high phosphate fertiliser after over-seeding to encourage seed germination and establishment.
  6. Please return to the use of a dwarf ryegrass / fescue seed mix; Barenbrug Platinum Fine Turf has given excellent results in the past.
  7. Start slit-time aeration using the Rotoknife as soon as possible.
  8. Before temperatures drop too low; sand top-dress, brush sand in and then aerate with the Vertidrain. Set the tines with ‘heave’ to break up compaction.
  9. Vertidrain three times if possible between now and April. Cover carries and roughs. Basically; tee to green and tree-line to tree-line.

10. During March 2019 over-seed the weakest areas, such as shown below, in several directions with the seed mixture as recommended. More general over-seeding should wait until September 2019. 


Prolonged hot weather will show the weaknesses in any irrigation system; these in terms of water pressure and sprinkler coverage. This appears to be the case at Dortmunder 

During my more than fifty years in the golf industry I have never encountered a course that operates its irrigation system solely from the mains without pumps or a water storage facility; either tank or reservoir. This shows that the outside mains supply has a high flow rate. 

I understand from Helge that the main water feed pipe enters the course at the top end of the par three course. This main feed is a 75cm pipe which then divides at a T junction into two 110cm pipes. If these sizes are incorrect I apologise and Helge can supply the correct information. In my opinion the main feed pipe needs to be much larger to ensure sufficient pressure is delivered to the sprinklers on all greens and tees. I am told that this is not the case with greens such as 12 not getting sufficient coverage. Certainly this is also true of green 9. Therefore a larger pipe should be installed during the coming winter months. 

Greens such as 9 and 13 should have a split system using two electro-valves so that sprinkler heads operate two at a time rather than all four heads at once as is presently the case.

All approaches should have irrigation heads fitted. I am impressed that the 10th approach is having heads installed by your own team. 

The illustration shown below is the type of ‘travelling sprinkler’ that could be considered for use on fairways. However please bear the following in mind; these can only be operated during the daytime as the main greens and tees system will be operating during the night. Therefore they will have an effect on play. Also they are slow; no more than one par four hole could be irrigated in one working day.


Chafer grubs continue to cause damage around the course; crows and badgers (dachs) cause visual damage digging for them. Controlling these birds and animals will not cure the problem as the grubs will continue to eat the grass roots resulting in turf lose. I believe that the Club can obtain a licence to apply the insecticide Confidor and this should be applied next spring as and where required. 

I am impressed with the drainage work carried out by the team on the right-hand side of the 7th hole. This area has always been soft and wet and the solution that put in place will not only cure this but it is also visually pleasing.

As you will be aware I work with Royal St Barbaras and Unna-Froendenberg as well as your Club. Comparrisons cannot easily or fairly be made as so many things differ from course to course. These include soil types, grass species, budgets and many other things. In my opinion your course is in as good as condition as can be expected taking the points covered in this report into consideration. I am confident that by working together as a team we can deal with these challanges and continue to move the course forward.

Peter A.Wisbey

Practical Turf Management Ltd                        20th November 2018

Next visit; March 2019