Scouting Report: July 23rd

The Illinois State Amateur Championship was held this week at Calumet Country Club. Superintendent Matt Harstad and the rest of the agronomy team had the course in tip top shot that tested the best golfers in the region.
I went into this week with my mindset on monitoring turfgrass conditions across the state after several rounds of hot and wet weather. However, I got to take a step back at times and see management beyond the turf.

Golf courses provide so much more than just a golfing experience. They are green spaces that promote ecologically diverse habitats for many species of plants, animals, and insects.

For instance, the out of play areas at Cantigny Golf Club are outfitted with many species of pollinator plants that serve as ecological habitats for many insects and other beneficial organisms.

Many other facilities are also promoting this practice. For instance, last week I observed similar efforts in Channahon, IL, at Heritage Bluffs Golf Club.

Although I have highlighted just two facilities, I am seeing many other golf courses take tremendous strides in providing these beneficial habitats. It may not be possible for every club, but it is a very rewarding experience for those that take the leap.
This week was almost a mirror image of last week. Humid conditions swept across the entire region and the rain was concentrated in the northern parts of Illinois.

In the last 14 days, areas in the south-central part of the state are running at a 25–50% deficient in normal precipitation. Irrigating and hand-watering is critical in sustaining many of our cool-season turfgrasses in that transition zone climate.
Further north, areas in the far northeastern corner of Illinois are almost off the scales in terms of precipitation amounts. This area has received more than 600% of normal precipitation in the last 14 days.

The high rainfall totals continue to cause ponding in high-value turfgrass stands. There isn’t much you can do when the water is rising up from the drains.
In other scenarios, over-run creeks and wetland areas could be contained with sand-bagging. As a preface, most of the time when we talk about sand-bagging on a golf course it is used figuratively to describe the practice of misrepresenting your golf ability. However in recent days, the phrase has a more literal sense.

High rates of rainfall on-top of water-logged soils has also resulted in brief waterfall formations.

A distinct plunge-pool with minor undercutting was observed this week in northern Illinois. I just hope beneficial organisms did not get trapped in the undertow.
This was another week of numerous pest reports. The majority of Illinois is considered a cool-season turfgrass climate. Cool-season turfgrasses are susceptible to many pests when air-temperatures and dew-points soar.
Weeds

Crabgrass is starting to form its own turf stand. This weed can easily take over in the heart of summer. This area was observed in central IL towards the outskirts of the practice play area.
Post-emergence control of crabgrass is difficult. However, the Hydroxyphenylpyruvate dioxygenase (HPPD) herbicides can be effective with multiple applications.

The HPPD herbicides inhibit carotenoid biosynthesis. Long story short, no carotenoids…no protection from harmful free radicals that accumulate in leaf tissue. First, the chlorophyll breaks down (hense…whitish plants) and once it intensifies, necrosis sets it.
The visible effects of this herbicide mode of action are easier to see from a distance.

This mode of action affects all turfgrasses. However, when the rate of product is adjusted, it affects turfgrasses differently. In this example, a HPPD inhibiting herbicide is bleaching the creeping bentgrass (the weed) and not the desirable Kentucky bluegrass.
Insects
The majority of superintendents have applied preventive grub control products. That critical in maintaining healthy plants into next year. So, we got that going for us, which is nice.

A surprising insect pest observed this week are chinch bugs. Recently, chinch bug damage has been observed at multiple golf courses across the state. The majority of the damage has been observed next to bunker banks. I have heard success stories with applications of bifenthrin. This product should be watered in immediately.
Diseases
Afternoon dew points above 70 degrees were conducive for disease development this week. Disease pressure was high from central Illinois northward. This is the time of year that higher rates and tightened intervals of fungicides may be necessary.

Substantial dollar spot breakthrough was observed this week at multiple locations. A number of ‘top shelf’ products where not able to extend protection towards the tail end of the labeled spray interval.
There are many factors that affect fungicide performance. Disease pressure is one. Other factors can involve fungicide deposition characteristics such as spray rate volume, nozzle selection, droplet size, and formulation. Another factor is plant growth.
Plants that are growing very fast due to microbial activity and rainfall, may be more prone to disease breakthrough. This could be due to the mowing off of fungicide residue on the growing points of turfgrass leaves.
Secondly, research by Dr. Paul Koch, has demonstrated that higher temperatures may lead to hastened fungicide decay on leaf material. The breakthrough in dollar spot control is likely a complex of several of the aforementioned variables. High disease pressure, rapidly growing turfgrass, and hastened fungicide decay are leading to a reduction of fungicide efficacy.

Anthracnose has been busy on creeping bentgrass and annual bluegrass putting greens. In Central Illinois, I observed rapidly developing anthracnose on a putting green surface that was treated with a strobilurin fungicide just 9 days prior to my visit. Speaking with the superintendent, anthracnose began to get more severe just 4 days after the application.
For those that have found success rotating in strobilurin fungicides for anthracnose control then keep steady on your program. However, for others, consider swapping out strobilurin fungicides with other chemistries to see if your anthracnose disease control program improves.
Chemically, I have heard success stories with using various formulations of fosetyl-alluminium, chlorothalonil, and polyoxin D. This is in addition to select SDHI’s and DMI’s as well as other contact fungicides and plant defense activators.
Culturally, the research team at Rutgers University has been publishing their best management practices for anthracnose control.
Other diseases have also sprouted this week under the humid conditions.

Brown patch on a stand of Kentucky bluegrass and annual bluegrass. Brown patch has also been observed on tall fescue and creeping bentgrass this week.
Kentucky bluegrass has also been attacked by various patch diseases this week as well.

These symptoms are likely caused by either summer patch or necrotic ring spot. Both diseases are suppressed by watering in fungicide applications.

Pythium blight was also observed this week in fairway and rough areas. Extended periods of leaf wetness is almost unavoidable after flooding conditions.

It has been so muggy that even crabgrass is getting punched by disease.
Trees and shade issues are starting to take their toll on high value turf stands. Most of the problem greens/collars I have observed are in areas pocketed by trees.

Sometimes it is easier to see the effects that trees have by looking at agricultural cropping systems. In this image, the quality and yield of corn will be much lower in areas affected by shade.
