We have surrenndered to the idea that some of our turf is not going to make it back from the winter. It is not as bad as we were thinking. We lost three tees and a couple slopes in the fairways. Here is a great artical from Virginia Tech about the winter kill 2015. Kevin
Virginia Turf @VAturf, #VAturf
s Page 1 Turfgrass Winterkill Update – 2015
Mike Goatley, Extension Turfgrass Specialist, Virginia Tech
Winterkill: I always like to tell people that you know what it is when you see it, but you just can’t tell
exactly what it is or why it occurred. The first week of May has brought some parts of Virginia the first
real evidence of significant winterkill of bermudagrass as golf course superintendents, sports field
managers, and sod producers have patiently waited to see if there was any life in areas that were slow
to green. Reports on living or dead Bermuda from folks that pulled plugs and brought them inside to
monitor greening have been quite mixed to this point. The damage seems to be more concentrated
from Richmond to Tidewater, and I am supposing that is because these areas of the state probably
didn’t have as much snow cover as the traditionally colder areas of the state did when the low
temperature extremes of January arrived. Where bermudagrass is grown in the colder parts of the
state, a significant snow pack during the low temperature extremes of February seemed to provide
adequate low temperature protection. When I reviewed my temperature data at the Turfgrass Research
Center here in Blacksburg during the period where our temps dipped to ‐2 and ‐6 F for the nights of the
20th and 21st of February, the uncovered control plots in my winter turf blanket research trial were still in
the upper 20s underneath 6+ inches of snow. Another observation on the value of the snow cover is
whereas we lost 75% of our NTEP bermudagrass variety trial in 2013‐14 (no snow and two nights of
subzero temperatures), it appears that the majority of the varieties have survived the winter of 2014‐15.
In 2014, predicting where the
bermudagrass damage was
going to occur was strangely
more difficult in that I saw
bermudagrass in certain
locations that survived (and
even thrived) under poorly
drained soils and northern
facing slopes. However, in
2015 the predictions on
where the grass is damaged
have been much more
consistent: poorly drained
soils, north‐facing slopes,
heavy traffic areas, fairways
shaded by the tree lines (Figure 1). Put any of these in combination with each other, and the damage is
that much more exaggerated.
Figure 1. There is a stark difference in the winter survival of this bermudagrass fairway
between the shade from the tree line and the center of the fairway.
Virginia Turf @VAturf, #VAturf
s
Page 2 Again, the standard cold tolerant varieties that have traditionally withstood the test of time in
Blacksburg variety trials (Latitude 36, Patriot, Northbridge, Midlawn, Yukon, and Riviera) have survived
fairly well as mature turfs. However, just about any bermudagrass (cold tolerant or not) that were
either harvested and/or established late last year are showing significant winterkill. Brian Walker of
Riverside Turf shared two photos of a Patriot bermudagrass production field harvested last fall (Figure
2). Scott Woodward of Woodward Turf in Culpeper confirms the same scenario at his farm. This type of
damage strongly suggests a short supply of bermudagrass sod in 2015.
Figure 2. This fall‐harvested Patriot production field in Charles City, VA shows the concerns with a late season harvest of
even a superior cold‐tolerant variety such as Patriot.
This type of damage always leads to questions of the turfgrass manager on “what did I do wrong”? In
most cases, nothing. Mother Nature constantly sends us friendly reminders of the trials and tribulations
of growing grass in the transition zone. One contributing factor has been the summers of both 2013 and
2014. Each were relatively mild summers that I would describe as fairly poor bermudagrass years in
terms of prime growing conditions during the summer months (of course, this has been a blessing for
those mostly managing cool season grasses). Much of the state has struggled getting that ‘100 days of
prime bermuda growing conditions’ that we feel are necessary in the transition zone to really have a
healthy bermudagrass stand that is fully prepared to survive a 4‐5 month winter dormancy period.
However, the damage we have experienced over the past two winters does give us reason to think
about possibly altering management strategies and situations, and to at least let your clientele know of
the challenges and how you are addressing them.
Two areas that I definitely think can be addressed (WITH the necessary approval and financial support)
are poor drainage and modification of shade lines. Anything that can reduce persistently wet soils is
going to improve the overall health of any turfgrass. Where possible, move the water away from these
persistently wet soils and you will be rewarded with the opportunity to really grow some grass there in
the future. The trees vs turf battle is never going to go away and there simply must be some level of
Page 3
compromise between golfers, the superintendent, and what to expect regarding turfgrass density and
persistence in part sun/part shade turfs. There is no better time to ‘educate’ greens committees etc.
than right now about how damaging winter shade lines can be for tree‐lined bermudagrass fairways.
The problem with the shade is not just the duration of the colder temperatures of the winter, but also
the reduced thriftiness of the turf in the first place from growing under low light conditions on a regular
basis. I understand that trees provide great beauty and function, are a part of the strategy of hole
design, and even an important safety component for people that drive the ball like me, but there almost
always is some potential for some selective thinning of trees (desirable) and ‘limbing up’ of trees (better
than nothing) in order to get more light to the turf. Again, take advantage of the opportunity to discuss
this with your clientele first hand on why the problems exist.
Another issue for which you can continue to educate your clientele on for its importance is the effect of
persistent, heavy traffic and how it increases the potential of winterkill. This is readily evidenced just
about every year for any major entry and exit points into greens, tees, and fairways and it is obvious
every spring between the hashes and 30 yard line markers on football fields and around the goal mouths
of soccer. Now is a great time to once again remind the users of the turf just what a difference could be
made if we could only distribute the traffic better. Signs, ropes etc. all help, but what is really required
in traffic management is an appreciation by all that we can make a difference one cart or one player at a
time if we simply keep this in mind.
If you have had significant damage, what are you going to do now?
If you return to bermudagrass for sports field or golf turf use, are there more cold tolerant varieties
available than what you have used in the past? And remember what was said earlier about short
supplies of bermudagrass this year as the damage extended well into the Carolinas in the winter of
2014‐15. Sprigging at 800‐1000 bushels per Acre rather than what I usually think of as our ‘minimally
acceptable standard’ of 500 bushels per Acre can greatly assist in achieving complete coverage of
bermudagrass as soon as possible (I would say no more than 8 weeks in an average summer… whatever
that is!). If you seed, prep the soil, be prepared to manage the irrigation and weeds, and I would use up
to 1 lb of pure live seed per 1000 sq ft of our improved seeded varieties. If you would like to talk to
Virginia Tech in more detail about how to utilize lower quality seeded bermudagrasses with the
improved seeded varieties as a means of saving money and enhancing the rate of coverage, contact me
to discuss the benefits of this approach based on our Virginia Tech research.
One thing I didn’t discuss but it is particularly appropriate for sports field managers (and an absolute
necessity for anyone in the golf business moving towards ultradwarf bermudagrass putting greens) is
the use of turf blankets for winter protection. For those of you pondering about whether or not a turf
blanket might be a good investment, remember that you can use the more translucent turf blankets
(typically the white or lighter colored blankets) to assist you in grow‐ins of both warm‐season AND cool‐
season grasses, in addition to winter protection. I attach the following picture (Figure 3) that I received
on May 7, 2015 from Mike Skelton of Culpeper Parks and Recreation Department. For three years now,
Mike has had great success establishing Riviera bermudagrass under non‐irrigated conditions by way of
dormant seeding and covering the installation with a turf blanket. This picture shows the results of a
March 23 dormant‐seeded bermudagrass that also received a ¼ topdressing of compost and a
quinclorac treatment for weed control. Mike has brand new bermudagrass turf that is already in need
of a mowing BEFORE most of us are even considering seeding bermudagrass.
Figure 3. The turf blankets are being removed on May 7, 2015 at Spillman Park in Culpeper, VA so that the March 23 dormant
seeded Riviera bermudagrass turf can be mowed for the first time.
Please let the Virginia Tech Turf Team know if it can assist you in any facet of your turfgrass
management programs.
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