Scouting Report: October 15th

HGT Kentucky bluegrass has made an excellent tee surface at Downers Grove Golf Club.

A little bit of rain has spruced up some of our playing surfaces this week. Bentgrasses, fescues, and bluegrasses look pretty great and play even better this time of year. This tee box was established with HGT Kentucky bluegrass. This is a high performing low-mow bluegrass that is being increasingly established as a tee-box or fairway surface.

Rapid recovery from divot patterns with Kentucky bluegrass tee surfaces.

Par 3 tees take plenty of punishment compared to par 4 or 5 tees. This bluegrass was able to recover quite rapidly from daily play. The divot pattern from 3 days ago is hardly visible from my vantage point.

7-day precipitation totals across the Midwest. Courtesy of NOAA.

Many folks in the area were able to cash in on the rain. The majority of the state received at least an inch of rain with locally heavy amounts mixed in. At the golf house, the rain didn’t fall all at once either. We seemingly had a constant drizzle for about 72 straight hours.

Recent rains have helped germination this week.

The rain and warm soil temps for this time of year has aided fall establishments. We observed a fair amount of germination this week at the golf house.

Recent rains have also helped newly transplanted flowers.

The rain was also beneficial towards newly planted flowers such as mums. These flowers are pretty common this time of years as many clubs are installing fall decor around clubhouses.

Many folks are timing cultural practices with rain events this week. Photo courtesy of D. Dinelli.

Most courses are doing their best to time much needed cultural practices around rain events. Many facilities are still trying aerifying, verticutting, and installing new drainage.

The recent rain and long wetness events has also caused a few pests to kick up this week.

Insects

Although not technically an insects, there has been a lot of earthworm activity lately. Earthworms in collar areas and on fairway surfaces.

Earthworm castings has increased after recent rainfall.

Mowing fairways with numerous earthworm castings can cause a brown smear across large areas.

Fat grubs were observed again this week.

I’m still seeing lots of fat grubs near the soil surface. Racoons and skunks continue to eat well throughout the region. Those that applied chlorantraniliprole have observed excellent control this year.

Weeds

There have been some unsuspecting grassy weeds pop up in some areas this week.

Corn plants can be ‘weeds’ too.

Many places use bunched up corn-stalks for autumn/Halloween decor. A consequence of being festive may be the accidental introduction of mature corn seeds.

These plants were likely introduced by the movement of decorative corn stalks.

Fortunately, this grassy plant can be controlled by a sharpened rotary mower.

Diseases

Last week Bipolaris leaf spot was active. This week I observed anthracnose activity on ‘Penncross’ creeping bentgrass.

Anthracnose selectively injuring creeping bentgrass plants compared to the surrounding annual bluegrass.

The superintendent told me that Poa has slowly been filling in this spot over the last few years. The bentgrass that is mixed in this area seemed to decline each year and the poa would take over.

Massive amounts of fruiting structures were observed near the base of ‘Penncross’ creeping bentgrass plants.

A closer inspection of the bentgrass revealed pretty severe anthracnose damage as indicated by the numerous fungal structures at the base/crown of the plant.

Fruiting structures were observed all the day the stem and stolon tissue.

The infection was equally bad on the stem/stolon of the creeping bentgrass plants. It’s interesting how the poa was unaffected by this strain of anthracnose but the ‘Penncross’ creeping bentgrass was severely affected.

Those that are battling anthracnose this time of year could bump up nitrogen inputs to grow out of infection. If a fungicide application is warranted, the use of DMI’s would be a great option this time of year. Most DMI fungicides also provide protection against dollar spot.

Dollar spots continue to expand in many locations in Illinois.

Dollar spot pressure was high this week. This time of year it doesn’t take long to go from ‘speckling’ to sunken spots. What I have noticed the past two weeks is how long the mycelium remains atop the plant canopy during the day.

Dollar spot mycelium can persist into the afternoon hours in shaded areas.

In shaded areas, the dollar spot mycelium was still ‘fuzzed’ by 3:00 pm on Friday. Long nights and a lower sun angle (less U.V. light) during the day can lead to rapid intensification of this disease.

Dollar spot break-thru was pretty common this week as a few courses elected to spray thiophanate-methyl after the rain made the soils soft.

Just a few days of dollar spot activity can lead to sunken spots in the turf.

Thiophanate-methyl is a great systemic fungicide against dollar spot. However, Sclerotinia homoeocarpa resistance to this particular chemistry has been documented.

Yellow tufts and white leaves

Symptoms resembling yellow tuft and ‘white leaf’ continue to scratch heads throughout the region.

Symptom of yellow tuft on individual plants.

Yellow tuft is common to see under cool and wet conditions. This disease is best characterized by profuse tillering of affected plants. This creates a witches-broom appearance.

Symptom of yellow tuft within the turf stand.

These affected plants can easily be pulled from the surrounding turf. The color of these affected plants can slightly more pale than surrounding turf. From a distance, yellow tufted plants may have a slightly more upright growth habit.

In most instances, yellow tuft can go away on its on in due time. It is caused by an oomycete. Therefore, traditional fungicides may not be that effective against this disease.

Another malady that traditional fungicides may not be very effective on is ‘white leaf’.

Close-up symptoms of ‘white leaf’.

Symptoms of white leaf disease were observed this week on creeping bentgrass, Kentucky bluegrass, and tall fescue. On creeping bentgrass, it has been observed on older cultivars and newer cultivars. White leaf is associated with phytoplasma that is thought to be vectored into host plants.

Stand symptoms of ‘white leaf’ on a creeping bentgrass fairway surface.

So far, white leaf is not causing substantial thinning to the turfgrass. However, due to the albino appearance of the grass, it can become a cosmetic nightmare.

The majority of white leaf symptoms are occurring on creeping bentgrass fairways. However, it has been observed on creeping bentgrass putting greens this week as well.

Symptoms of ‘white leaf’ on a creeping bentgrass putting green.

The reason why there is much less observed white leaf activity on putting greens is unclear.

Close up examination of ‘white leaf’ symptoms on a creeping bentgrass putting green.

Putting greens often receive much more inputs than fairway surfaces. This include more cultivation programs and at times a different array of insecticides and fungicides used. However, there are still many more questions than answers.

Please don’t hesitate to email me (jbenelli@CDGA.org) any interesting observations you have made about the occurrence of this malady. I’m interested in knowing when symptoms appeared and disappeared. What surfaces this occurred on (fairways, greens, or both). Were there any differences in the insecticide or fungicide applied on these surfaces. Timing of aerification between fairways and greens.

As of now, there aren’t too many management recommendations. We have seen this malady being able to track from mowing patterns and drainage. It may be wise to mow the most affected fairways last.

Looking ahead

Plunging soil temperatures and recent rainfall could ramp up take-all patch activity. Courtesy of the Illinois State Water Survey.

With a number of diseases affecting the foliage of the turf right now, it is easy to forget what could be happening below the soil surface.

Recent rainfall and plunging soil temperatures has me thinking about preventative take-all patch applications for many in the northern portion of the state.

Twitter: CDGATurfgrassProgram

Email: jbenelli@CDGA.org