Root Pruning

Last summer we began experiencing severe drought symptoms on a few of our tees  No matter how much water we applied, these tees would constantly dry out.  After probing around in the soil we realized that the roots from nearby trees had grown into the tee mix and were causing our problem.  After seeing the impact tree roots can have, I realized that certain areas of the rough that consistently burn out during the summer were similarly being negatively effected by tree roots.

To help solve this problem we rented a machine to prune back the tree roots.  Pruning tree roots is a common practice on golf courses.  Traditionally root pruning is performed every 4 or 5 years and is done using a ditch witch trenching attachment.  This method involves first the removing the sod, then digging a trench with a ditch witch.  The open trench is then back-filled with soil, compacted and the sod replaced.  It is a time consuming and labor intensive process.  The machine we rented cuts through tree roots in very little time with minimal labor.  Two large rotating blades slice through the soil and through any tree roots.  All that is left behind are two thin lines in the turf. 

Later this summer as things dry out we will see the benefit of this process.  Without the competition from the tree roots we will have a better chance of maintaining quality turf throughout the summer.

Pruning tree roots

The imants root pruner

Blades of root pruner

No clean up necessary

Easily cuts through large tree roots

#5 Green on May 20, 2014

Although progress has been made, recovery of the winter damaged greens continues to be slow.  A cool spring has slowed the growth of the grass and delayed seed from germinating.  However as the weather continues to warm up I am confident we will see faster recovery.  To speed the process along, we decided to sod the most heavily damaged areas of the collars on the 4th and 5th green.

Re-sodding #5 collar

We also have been taking plugs of bentgrass from our nursery green and plugging out the worst spots on the greens.

Removing bentgrass plugs from nursery green

Repairing #4 green with bentgrass plugs

Course Update

Beginning Sunday afternoon and ending Monday evening we aerified and topdressed all 18 of our greens.  The greens were aerified using 3/8" hollow coring tines on 1 inch centers.  After the plugs were cleared off the greens, sand was applied and worked into the open holes. Today fertilizer will be applied to get the grass growing. We will roll the greens daily to smooth and firm the surface and in a few days after the sand has settled into the canopy we will start mowing the greens.  Because the growth of the grass tends to be a little slower in the spring, we like to use the smaller 3/8" tines to shorten the recovery time.  The greens should be completely healed in about 2 weeks.  Although aerification is despised by golfers and maintenance staff alike aerification remains an important cultural practice.  Aerification removes unwanted thatch and allows good air exchange to the root system helping the turf to survive the stresses of summer.

The fifth green continues to recover nicely although it never seems to happen as fast as we would like.  The cover definitely helped speed up the recovery process and allowed us to get the bentgrass seed to germinate.  As temperatures continue to rise and the green recovers, the green will be available for limited play and eventually be open all the time.  Looking at the green every day, it is sometimes hard to see the progress we have made.  Here are some before and after photos that show how far the green has come in one month.

#5 Green on April 16, 2014

#5 Green on May 10, 2014

#5 Green on April 7, 2014

#5 Green on May 10, 2014

Bentgrass creeping over damaged areas

New Bentgrass seedlings

Road to recovery

The road to recovery has begun.  On Friday April 25th we over-seeded the 5th green with creeping bentgrass.  The following is a description of  the process we used.

The first step is to prepare the green for seeding by using a special tool called a Job Saver tine. These tines make small shallow holes in the green that hold the bentgrass seed.

Aerifying #5 Green with Job Saver tines

Holes made by Job Saver tines

 Next we seeded creeping bentgrass into the open holes.

Seeding with bentgrass

 Once the seed is down, we apply a layer of sand to the green and then work the sand into the holes with a drag brush.

Topdressing with sand

Brushing in the sand

After the sand is brushed into the holes we roll the green, irrigate and cover with a tarp.  The tarp will act like a greenhouse to help heat up the soil.  For bentgrass seed to germinate we need soil temperatures in the 60 degree range.  With the right environmental conditions bentgrass usually germinates in 5 to 7 days.  We still have a ways to go but these are the first steps in getting the greens to recover.

Holes filled with sand and seed

Tarp covering green

Winter of 2014

After experiencing one of the longest coldest winters in recent memory, we have anxiously awaited to see what effect it would have on the turf. While most of the turf came through the winter fine, it is now apparent that we did suffer winterkill on a few of our greens.  The damage is most noticeable to the Poa annua on greens #4, #5 and #6.

Winterkill on #5 Green

WinterKill

Poa annua or annual bluegrass is a grass species that is particularly susceptible to winterkill primarily through a process known as crown hydration.  Crown hydration generally occurs in mid to late winter when a day or two of warm daytime temperatures causes snow to melt and collect in low areas.  The combination of warm temperatures and available water enables the grass plants to start absorbing water or hydrating.  If the warm weather is then followed by freezing temperatures, ice crystals form in the plant, rupturing cells and ultimately causing death.  Annual bluegrass tends to break dormancy quickly when subjected to above-freezing temperatures and free moisture and therefore is very susceptible to this kind of damage.  Creeping bentgrass on the other hand is late breaking dormancy and is virtually immune to crown hydration.  This is why when you see the greens that were affected you will notice that the annual bluegrass is severely damaged while the creeping bentgrass is very healthy.

Damaged Poa annua and healthy bentgrass

Recovery

In the short term we will look to reestablish the damaged areas of the greens as quickly as we can.  However this process can be agonizingly slow and challenging in the spring because of the cool, cloudy conditions that often persist.  The first step in promoting recovery is getting seed into the ground.  Once the weather warms and soil temperatures increase, we will begin the process of inter-seed creeping bentgrass into the damaged areas.  Although inter-seeding has given mixed results, success can be improved by using new improved bentgrass varieties and by utilizing tools such as the Job-Saver aerator attachment.  This tool produces numerous small, shallow holes for the seed to germinate in.  After seeding it may be necessary to apply a turf cover over the green to maintain adequate soil temperatures for germination to take place.  

Turf Cover on #5 Green

The second step to successful recovery is keeping traffic off the greens. Traffic sets tender, weak turf up for more injury.  Also newly emerging bentgrass seedlings are susceptible to wear injury.  Opening greens too early usually doubles the recovery time, and it reduces the amount of bentgrass established.  While no one hopes for winter injury, it does provide an opportunity for the existing bentgrasses to increase and to establish new and improved species of bentgrass. By increasing our bentgrass populations we would be less likely to encounter this type of damage in the future.  Other strategies employed in recovery will include reducing stress by mowing and rolling these greens less frequently, raising mowing heights, using solid front rollers on the greens mowers and providing light frequent fertilizer applications to stimulate new growth.  How long the recovery will take is difficult to say.  A lot will depend on the weather but I suspect it will take several weeks to completely heal. 

Winter Update

As winter continues to linger there is a growing concern among many superintendents in the northeast as to what effect this winter will have on the turf. 

Snow cover is good for the golf course.  Snow acts as an insulating blanket that protects the grass from the extreme low temperatures and harsh winter winds.  Ice on the other hand is not good.  Ice covering the turf prevents CO₂ gas from escaping into the atmosphere.  Prolonged exposure to high levels of CO₂ can lead to turf loss.  As a rule of thumb bentgrasses can tolerate up to 120 days under ice cover while Poa annua can only survive about 45 days.  Because our greens at Huntsville are a mixture of bentgrass/ Poa annua and we are approaching 45 days under snow and ice coverage, my assistant Casey Sheehan and I went for a walk around the course to inspect the greens for possible injury.

Our first stop was the 8^th green.  This green was covered with about 3 inches of snow and a 1/2” thick layer of ice.  We removed the ice and looked at the turf underneath.  Everything looked good.  Most importantly, when we uncovered the turf, we were not meet with “the smell of death”.  “The smell of death” is a term superintendents like to use to describe the odor that dead turf gives off under ice.

Next we proceeded down to the 4^th and 5^th greens.  These greens had about 5 inches of snow covering a 2 inch thick layer of ice.  The thick ice and melting snow made it a little harder to see the turf but from what we observed the grass still looks good.

We also took a small sample of the green and brought it back the maintenance building for observation.  If the grass greens up and starts to grow, we will know that the turf is still healthy.

There is much debate about the best way to deal with ice on a green.  Some superintendents choose to remove the ice.  However there are two problems with removing the ice.  First, the process of removing the ice itself can cause significant damage to the green.  Secondly, if you remove the ice and expose the turf to warm temperatures and then get a period of low temperatures you can lose turf through what is known as crown hydration.

Based on what we have observed so far, we have decided to leave the snow and ice in place and continue to monitor the health of the greens.  If it is determined that the ice is causing problems then at that point we will take the necessary steps to prevent further turf loss.

Some parts of the golf course have already lost its snow cover.  All of these exposed areas look good.  We have not seen any ice damage and there is no sign of snow mold.  Snow mold is a fungus that can attack the turf in the winter.  We treat for this disease preventativly in the fall and I am happy to say that those applications seem to have been effective.

With warmer temperatures in the forecast, we hope to loose a lot of the remaining snow cover and prevent any ice damage from occurring.

Hydraulic leak



One of a superintendent’s worst fears is a hydraulic leak, especial one that occurs on a green.  As luck would have it on Sunday July 7 this is exactly what happened at Huntsville.  



#13 Green immediately after leak



The leak was caused by a failing oil seal on one of our greens rollers.  The leaking oil resulted in small spots and thin lines of damaged turf.  Unfortunately the operator did not notice the leak until several greens had been damaged.  The greens affected were #3, #5, #7, #10, #12, #13 and #17.

Many people have asked why the operator did not stop sooner.  Hydraulic leaks however can be very difficult to detect initially, particularly when the leak is small like the one we experienced.  Hydraulic oil is a clear liquid and it has no odor. Noticing hydraulic oil on wet grass in the early morning light can be almost impossible.  It is not until sometime later that the damage becomes very apparent.



Fortunately for us the leak was light resulting in mostly superficial damage.  The damaged turf should recover in a week or two.



#13 Green five days after leak



We are now carefully inspecting all of our rollers and replacing oil seals and hydraulic motors as needed to prevent this from happening again.