Spring No More! Record Heat, New Pests (Waitea, Sod Webworms, Quackgrass), plus a Divot Repair Research Update

CDGATurfgrassProgram
6 min readMay 13, 2022

Three words are all that is needed to summarize May’s second week in Illinois. Spring no more! The radio news went something like this: “Last night’s low of 74 degrees set a new record. Yesterday’s first official high of 90 degrees set a new record, because Chicago normally doesn’t see its first 90 degree day until June 5th.” Always humbling to be on the receiving end of Mother Nature’s play book isn’t it? We forgot about too much rain. The sky was partly cloudy or was beaming FULL SUN. A new nemesis entered the landscape = record heat.

A good reminder of how all our calendar-based planning goes. It can go out the window (so to speak). Needed spring applications and regular mowing didn’t always happen (rain). And this week was to be catching up during some mild, mid-spring weather. Instead, it’s here (summer). This is why we like it? The outdoor environment. We are never 100% sure of what to expect. Record-breaking heat on the heels of a record wet and cloudy spring. Why not.

Spring 2022 rapidly progressed. Most deciduous trees are with leaves. Oaks (Quercus) emerging leaves are soon to pass the size of mouse ears. The landscape has more color. Redbuds (Cercis), and lilacs (Syringa), and crabapples (Malus) and viburnum took over with colors of pink, magenta and purple. The olfactory part is there too. Wait for a breeze or stop and smell.

The golf courses (and greens) are progressing too. Cool-season creeping bentgrass, Agrostis stolonifera, is just about fully awake. Bentgrass is always behind growth-wise versus Poa annua on greens. Meanwhile Poa moved into an even higher gear. It went from 0 (no flower) to 100 or near peak seedhead production. It was 7 days of rapid growth of everything. When you look down the turfgrass jumped (several inches) as well. A new word says it all. Mow.

Image 1. Bob Berry Sunshine Course: Poa seedheads (whitish appearance in foreground) quickly appear. Settle, May 12, 2022

Weather Summary (May week 2) by Shehbaz Singh, MS

Air temperature. The second week of May was like peak summer-time in Chicago. Temperature on most days this week ranged from 70 to 91°F. On May 12th (Thursday), a new record max air temperature of 91°F was experienced. Far from normal. At this point in May, normal air temperature should be from 48 to 72°F. You have to go back a decade (2011) when this kind of air temperature pattern was experienced in early May — a high of 92°F was recorded. For comparison, in 2021 the Chicago air temperature at this point ranged from 39 to 71°F. Quite lower than what we are experiencing.

Figure 1. Current Chicago air temperatures (blue bars) versus normal range (brown band) in May, 2022.

Precipitation. Chicago area didn’t experience any rainfall during the second week of May month. However, accumulated precipitation for may month at this point is about 1.92 inches. The normal accumulated precipitation at this point is about 1.93 inches. In 2021, at this point of month only 0.3 inches of rainfall was experienced in Chicago area.

Figure 2. Spring rainfall in Chicago (green line) versus normal (brown line). May’s 2nd week saw no rain.

Weather Forecast. Temperatures next week are going to be better (less warm). Partly cloudy to mostly sunny conditions expected. Air temperature is predicted to be mild and range from 50 to 80° F on most days. Chances of rainfall are low. Windy conditions are predicted by week’s end.

Poa Seedheads Quickly Arrive in 2022

Newer timings to suppress Poa seedheads begin in the fall. This is part of regular maintenance of turfgrass in northern environs. Fall timing makes sense because spring weather (frequent rains) can be frustrating. Additionally, rapid warm-ups in spring are not uncommon. This equates to rapid changes in GDD (growing degree days). Weather modeling for things like Poa seedhead development. For more on this see: “Adding a late fall application of Proxy (ethephon) before two traditional spring applications improves seedhead control of annual bluegrass”. A 2020 publication in Applied Turfgrass Science conducted at multiple USA locations. For more click here.

Image 1. Poa annua seedheads appear in the rough at Bob ‘O Link Golf Club, Highland Park. Settle, May 11, 2022
Figure 1. Spring timings for Proxy/Primo to suppress Poa seedheads likely difficult in 2022. April saw few days that allowed golf course superintendents and staff to make needed applications. Then came heat in early May. A rapid warm-up quickly sent optimal timings (green color) further north. gddtracker.msu.edu

1st Pest Issues Arrive — All 3: Disease, Insect, Weed

Scouting. As a grower, one of our main tasks is to always be in touch with what is going on. It is called scouting. This is especially important when it comes to golf greens. Staff and superintendents must “scout” for a lot of things when it comes to greens. Pests (disease, insects, weeds) come to the top of the mind. But there are many other aspects which can include; soil moisture, plant health, equipment wear, foot traffic wear, localized dry spots, ball marks, adequate air movement, light levels, etc. With frequency, golfers help out superintendents when it comes to scouting of greens. It’s all good.

Waitea Patch. Fluorescent yellow rings of Waitea appeared on a Poa annua collar of a golf green during a rapid warm-up in Chicago. It is diagnosed just as we would a Rhizoctonia disease. It is known by the common names of Waitea patch and brown ring patch. It naturally disappears by midsummer. Historically, the CDGA conducted research at Biltmore Country Club in N. Barrington, IL. One important finding was that the fungicide thiophanate-methyl actually increased Waitea patch relative to the untreated check. For more click here.

Image 1. Waitea patch impacting the Poa annua on a practice putting green in Chicago. Settle, May 10, 2022

Sod webworm. At Bob Berry Sunshine Course in Lemont our scouting found minor v-shaped damage (web + sand covered surface tunnels) on a creeping bentgrass green. Additionally, bird feeding holes were found. Both are signs of sod webworm activity. They are able to overwinter and this lets them be active in the early spring. Sod webworms surface feed and activity is at night. If control is warranted, apply an insecticide labeled for sod webworms and do not water-in. An excellent entomology textbook to have on your desk? Turfgrass Insects of the United States and Canada by Patricia Vittum et al.

Image 2. Signs of sod webworm damage on a creeping bentgrass green. Note the damage is a V-shape or can remind you of a boomerang (so says Dr. Randy Kane). Settle, May 12, 2022

Quackgrass. Quackgrass or Elymus repens can be identified by its tendency to be noticeable in spring (a cool-season grass). Additional characteristics make its identification relatively easy; its blue-green color, its clasping auricles, and its ability to produce rhizomes. Quackgrass is not easy to control. A non-selective herbicide like glyphoste is commonly used for best results. This means the best measures are cultural practices that exclude its introduction. Inspect all seed, sod and any landscape material for signs of quackgrass prior to introduction onto a property. Some good news in 2022. Quackgrass is not as problematic a weed as it once was in the 1980s or 1990s when it was common and considered a top 5 weed in most crop fields. Recent information on quackgrass was provided by University of Illinois Extension.

Pest 3. Weed: Quackgrass growing in a fine fescue rough at a Chicago golf course. Settle , Mar 11, 2022

Divot Repair Study Update. The two divot repair studies (one on a creeping bentgrass tee and one on a Kentucky bluegrass tee) on Bob Berry Sunshine Course began 21 days ago. This study is being conducted in collaboration with Zach Nicoludis, USGA Green Section. Initial ideas were generated by the CDGA Green Committee (Research). Shehbaz Singh has an update below.

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CDGATurfgrassProgram

Written by Derek Settle, PhD & Shehbaz Singh, MS. Mission: Provide science-based turfgrass research and diagnostics to 400+ member golf courses/superintendents.