SURVEY QUESTION

All: When is the last time you apply nitrogen on warm-season turfgrass for the season?

Mid-August
Late August
Early September
Mid September
Late September
October

Update (10/23/2020)

It's Virtually Winter

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Weather

First Frosty Dip

  1. A warm start to the month dipped into the first frost in mid Oct. – MU Climate Center
  2. Temperatures over the last 30 days has been delightfully average. – MU Climate Center

Oddly both August and September ended with below average temperatures in MO, which resulted in a prime growing and seeding environment for cool-season grasses. The mild, below average September temperatures surged slightly in early-mid October, and then crashed back down in mid-October resulting in our first widespread frost. The frost event occurred a little earlier in central Missouri than the normal October 21st date indicated by climatology. To get more in depth analysis of frost/freeze data for Missouri go to https://ipm.missouri.edu/frostfreezeguide/.

Wetter Weather (Finally)

  1. Departure from average rainfall in the last 30 days. The West was a droughty mess. – MRCC
  2. Fortunately, Missouri is in the bullseye for rainfall over the next week. – NOAA

As good as the temperatures were, seeding of cool season grasses needed supplemental irrigation in most areas as precipitation helped very little during our fall seeding window. Rainfall totals for much of the region not impacted by the remnants of hurricane Delta in early October are very low, 2-4 inches below normal in the past 30 days for many areas, particularly in the SW portion of the state.

Wintry Blast from Canada and Snow Flurries?

  1. Winter in late fall may be a reality next week. – NOAA
  2. Increased precipitation chances and perhaps snow next week? – NOAA

Fortunately, Missouri is in the bullseye for wetter weather over the next week as the region stands along a frontal boundary with cool air to the north and warmth in the south. Two – three inches of rainfall (which started earlier this week) will serve to quench the thirst of young seedlings, and release fertilizer for late fall recovery and winter preparation of cool-season turfgrass swards. To answer some recent questions, we are presumably past the time to throw seed, except for the southern portion of the state. Soil temperatures have dipped in the mid to low 50s (click here to view in MO) and next week's forecast with the region sitting in cooler Canadian air won't help much to get them back. Some weather reports even indicate a chance for snow flurries next Monday or Tuesday indicating fall may in fact be ceding its grip to winter. The thermostat in the car or truck may slide to red for a while.


A Winter Outlook?

Predicting Persimmons?

  1. Folklore states the shape of the persimmon seed cotyledon predicts winter severity.
  2. Sampled persimmon seeds in MO show spoons and knives.

With the prospects of winter upon us and zoysia and bermudagrass entering into dormancy, our recollection of harsh winters like 2018-19 still permeate. Winter predictions abound from meteorologists and folklore alike, and below are a review of a few.

  • Persimmon – Sarah Havens, a field extension specialist in natural resources at MU, gave an interesting summation of the persimmon seed prediction model as a forecaster granted by nature. The shape of the persimmon's cotyledon in a ripe seed is believed to act as the indicator, with a fork shape indicating the winter will be mild, a spoon forecasting a lot of snow, and a knife showing the winter will be bitingly cold with temperatures that "cut like a knife." Seeds surveyed throughout the region have cotyledons shaped like knives or spoons, which wouldn't be great news. Wonder if persimmons grown at Arrowhead stadium would always have knife shaped cotyledons?

  • Wooly bear caterpillar – These common fall caterpillars have alternating black and rust-brown colored bands. Legend has it that if the black band is wider than the rust- colored, a harsh winter is in store, but scientists will say the markings are indicators of prior conditions not future. I haven't found one yet this fall, so can't comment. Festivals are held to celebrate this odd weather predictor… seriously.

  • The Old Farmers Almanac, founded in 1792, is also a common winter indicator. The almanac forecast (which can be found here) predicts a mild winter for the Heartland (Region 10) with below normal snowfall and precipitation.

  • On October 15th, the NOAA (National Oceanic & Atmospheric Administration) released their winter outlook, so the scientists have weighed in based on the temperature of Pacific Ocean waters. A La Niña is a cooler than average water temperature across the tropical Pacific Ocean that shifts back and forth with warmer temperatures (El Niño) in what is termed the ENSO (El Niño-Southern Oscillation). Their outlook is for cooler, wetter (and snowier) conditions in the North and warmer, drier conditions in the South due to a strong La Niña climate pattern. What does this mean for our region? Equal chances of above or below temperatures and above or below precipitation, or considerable swings in temperatures and rainfall in a very short period. So, basically normal Missouri weather without rhyme nor reason.

Virtual Field Day and Upcoming Conferences

In our new normal, which I hope doesn't last much longer, we've been and will be putting out virtual content. Below are a few of our current and future offerings.

  • The South Farm Virtual Field Day was released this past Tuesday, with turfgrass research highlights provided by my program and the program of Dr. Xiong. We detail our current research involving nematicide evaluation, putting green disease control and our turfgrass variety trials. To access these videos, go to https://southfarm.missouri.edu/field-day/.
  • Our IPM Youtube series (https://www.youtube.com/MUIPM) highlights snippets from our weekly Horticulture town halls that concluded last week. Most are from horticulture or production agriculture, but several highlight topics such as lawn fertilization, seeding and soil testing.
  • The Carolinas GCSA Turfgrass Conference entitled "Conference Comes to You" starts on November 2nd with 30 seminars in 30 days. My seminar will be towards the end on Thursday, December 10th at 1 pm EST, and will cover soilborne disease management on cool-season turfgrasses, particularly creeping bentgrass. This unique concept of seminars is a win-win since it delivers programmatic funding back to the speaker's programs to continue research progress. Without MoGIC and some other conferences being possible due to the pandemic, I encourage you to consider this a viable alternative. For more information see https://conferencecomestoyou.org/.
  • Pesticide applicator training – On the western side of the fence, I will be presenting in the Kansas Commercial Pesticide Applicator Training on Friday, November 13th (click here for more information). In Missouri, we will also be holding our normal "road show" virtually through a Zoom format throughout January 2021. Stay tuned for more information on scheduling and registration.

Quick Hits

Newly seeded variety trials

  1. New Kentucky bluegrass variety trial. Seeded 9/16. Photo 9/30.
  2. New NTEP bentgrass putting green variety trial. Seeded 9/16. Photo 9/30.

  • New Variety Trials Planted – We established two more cool-season variety trials at the MU research farm in mid-September and (with a bit of irrigation) they are growing in nicely. A Kentucky bluegrass trial in association with Columbia River seeds was established on Sept 16th with 52 new varieties to go along with the 50 that we established last year. The 2020-2025 NTEP creeping bentgrass putting green variety trial with 20 entries was also established on Sept 18th. This trial has six commercially available cultivars acting as standards, including Penncross, Penn A-1, Piranha, Barracuda, Declaration, and L-93 XD vs. fourteen experimental cultivars. For more information on this trial and our warm-season putting green trial in St Louis see the virtual field day video at https://southfarm.missouri.edu/field-day/.


  • Large Patch Symptoms
    Just a little reminder that the large patch pathogen infects the leaf sheath, not the leaf.

    Warm-Season Turfgrass Notes – With the early wintry weather forecast and warm-season grasses crashing into dormancy, many fall large patch and spring dead spot preventives are presumably out and perhaps completed by now. A few notes below on putting the warm-season grasses to bed below.
    • Remember that spring dead spot is a soilborne disease and fungicides should have been irrigated in post-application. Also, the large patch pathogen attacks at the leaf sheath (see photo) and not the leaf itself. Therefore, applications made in a higher water volume may be more effective as found in University of Tennessee research by Benelli and Horvath.
    • With a cooler than average September, the 70-degree soil temperature threshold for applying large patch and spring dead spot preventive fungicide applications was considerably earlier than last year and much more in line with our average mid-September time frame (see below). This was obvious in our field plots as large patch also occurred in mid-September.
    • In 2021, reconsider your late summer/early fall nitrogen application and mowing plan on warm-season turfgrass. Great collaborative research by researchers at Clemson and Virginia Tech (https://twitter.com/HutchensWendell/status/1317162508239634432) indicates increased color retention with higher mowing and slow release N application later in the season. This builds upon prior research by Goatley, Richardson and others showing no increase in winterkill with fall N applications and jives with our experience here at the MU turfgrass farm with low N bermudagrass zoysia swards being more susceptible to severe winterkill.




  • Lee Miller

    Extension Turfgrass Pathologist
    University of Missouri
    turfpath@missouri.edu
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