|
1997, No. 3
1997 So Far
We are well into 1997 and, again, the growing season started in unusual fashion.
By examining the abnormal weather in Champaign-Urbana, a general idea of weather conditions elsewhere in Illinois is possible.
Champaign-Urbana Weather
- During the last week in March and the first week in April, temperatures were above normal.
During this time, turf growth started with a bang, but was slowed (or almost stopped) by cold temperatures during the remainder of the month.
Additionally, April's precipitation was almost three inches less than average.
- This year saw the fourth coldest May on record; the average temperature was 5.4°F below average for the month.
- During the first 15 days of June, the mean daily temperatures were anywhere from one- to twelve-degrees below average.
Thereafter, June's latter half finally reversed this trend when mean temperatures were 5°F above normal.
Precipitation during June was again below normal by 1.7 inches.
- On July 6, soil temperatures in Champaign-Urbana were still less than 70°F at the 4" and 8" levels.
Turf Responses
Several turf growth responses to these aberrant climatic conditions have been observed.
- While turf shoot growth was slowed by the cold, dry conditions, rooting appeared to be good; most turf managers indicated their turf to be well-rooted going into summer.
- Conversely, thatchy turf seemed to be damaged during spring dry periods.
This is most likely due to the lack of adequate rooting through the thatchy layer into the soil.
- Spring-seeded turf germinated slowly due to cool soil temperatures, and, in some cases, a lack of precipitation.
Once again, this indicates the benefit of seeding during the late-summer - early-autumn period.
- Annual grassy weeds germinated later than normal.
The window to apply preemergence herbicides was longer this year than most.
In the northern half of Illinois, annual grasses seem to be present in below-average amounts this year.
White clover is the current main weed problem; its presence is due to cool weather and little turf response to nitrogen applications.
- Several diseases have been common.
Pink snow mold (Fusarium nivale) was common throughout the state through early June.
Some turf managers in the St. Louis area complained of cold weather pythium problems, only to learn following diagnosis that the problem was, in fact, pink snow mold.
Leaf spot on our Kentucky bluegrass fairway trial in Urbana was very active through mid June.
It has since improved.
Red thread in our perennial ryegrass trial has been present since mid June and continues to rage.
At Present
- Dr. Randy Kane reports seeing active take-all patch on several golf course fairways.
According to Randy, "... the disease can successfully be treated with Rubigan or Heritage fungicides in preventative fall and spring applications at higher labeled rates."
Dr. Kane also reports seeing large amounts of dollar spot.
He indicates that, "Traditional controls, for the most part, are taking care of dollar spot."
- Three other problems appear to be common.
Ants, localized dry spot, and fairy ring are being seen in abundance.
The 1997 Illinois Commercial Landscape and Turf Pest Management Handbook indicates that ants can be treated with Dursban or diazinon where they are a problem.
Localized dry spot problems can be improved through activities that open the soil and allow moisture to infiltrate including aerification or hydrojecting; wetting agents have also proved to help the condition.
Finally, nitrogen fertilization has been successfully used to mask symptoms of fairy ring in turf.
(TOM VOIGHT)
|
