IATurf Blog has moved to https://www.extension.iastate.edu/turfgrass/

Iowa State University Turfgrass is pleased to announce the launch of its fully-featured website https://www.extension.iastate.edu/turfgrass/. The new site has extensive content including blog posts, publications, research reports, and news from across the state of Iowa. The highly successful IATurf Blog that reaches thousands of individuals will now be accessible from your tablet and phone. Don't worry, we made sure to add all the previous blogs to the new site!

The new website is designed to assist turf managers across Iowa with a one-stop shop for everything turfgrass. The website focuses on making information available to all individuals with a vested interest in turf industry, as well as highlight specialized advice and turf solutions. As part of our objective to provide critical information on the turf industry, Iowa State is proud to introduce the new website. Along with the launch of the new website, there are nine new publications added to the Iowa Extension store.

The first set of publications address common homeowner questions.  As temperatures warm and the calendar steadily marches forward, people across Iowa will soon find themselves working in their yards on a regular basis. With this work in mind, Iowa State University Extension and Outreach has published four publications to serve as guides for residential yardwork. The full press release highlighting the publications can be found here! The following publications can now be found on the new site under the publication tab.

“Sodding a New Lawn”, (HORT 3033)
“Mowing Your Lawn”, (HORT 3047)
“Management and Control of Summer Patch” (HORT 3049)
“Organic Turfgrass Fertilization” (HORT 3031)

In addition to the general homeowner publications, five new publications focused on athletic field management were released. These focus on the planning required to keeping Iowa athletic fields aesthetically pleasing and more importantly safe. Managing traffic, interseeding and general maintenance of the field before, during and after the playing season are all important aspects to providing a smooth, even playing surface.

The full ISU press release can be found here! The following publications can also be found on the new site under the publication tab.

“Preventing Compaction on Athletic Fields” (HORT 3020)
“Tips for Athletic Field Seeding and Irrigation” (HORT 3022)
“Managing the Field within the Field” (HORT 3046)
“Putting the Field to Bed” (HORT 3048)
"Topdressing Athletic Fields" (HORT 3050)

Check out the new website and let us know what you think!

SPEEDWELL IN DES MOINES IN BLOOM

Nick Christians
March 11, 2016




The picture below is from Larry Ginger of American Lawn Care.  It is of Speedwell at the edge of a lawn in Altoona, Iowa, by Des Moines.  This is likely Persian speedwell (Veronica persica) also known as creeping Speedwell, Common Field Speedwell, or Winter Speedwell.  It is commonly found in Iowa, although I do not see a lot of it in central Iowa.  It has opposite, rounded, toothed, leaves and forms a dense mat runners in the lawn.  It generally lives as a winter annual and likely germinated in the fall of 2015.   It is surprising to see it in bloom in early March.

Speedwell is known for its heart shaped seed pod (see below).  This picture was taken on campus from another sample of common speedwell.

It is difficult to control with standard broadleaf herbicides and may persist when other broadleaves have been controlled.  Applying 2,4-D alone will unlikely be successful. A combination product with at least 3 ingredients, including dicamba and a pyridine such as triclopyr or fluroxypyr will likely give the best control. Repeat applications may be necessary. 

 Nick Christians
January 29, 2016

Georgeanna Heitshusen leaves today for the Super Bowl internship sponsored by the Toro company.  Georgie is the first female to win the internship.  This honor goes to one turf student each year in United States.  She is the 3rd ISU student in the last 5 years to be chosen for this honor.

Josh Lenz, a turf graduate student at ISU and former internship winner, is also at this year's Super Bowl helping to prepare for the game.


 

 You can find a news clip on Georgie and the Internship at:

http://whotv.com/2016/01/28/super-bowl-internship-takes-root-for-isu-student/

DOLLAR SPOT TRIAL AT IOWA STATE-2015

Nick Christians

December 8, 2015

nchris@iastate.edu

The following is a report on a dollar spot trial conducted at the research station this past summer.  The primary objective of the work was to evaluate the effect of an experimental adjuvant on disease control, but there is a lot of good information comparing the different fungicides.  We had a great year for dollar spot at the station.

KALO FUNGICIDE/ADJUVANT TRIAL-2015

Nick Christians and Dan Strey

Iowa State University

Objective

To compare the control of Dollar Sport caused by the fungi Sclerotinia homeocarpa on creeping bentgrass turf with 7 commercial fungicides applied with and without Kalo’s  KA-9107 experimental adjuvant.  

Materials and Methods

The trial was conducted at the Iowa State University Horticulture research station near Gilbert, Iowa.  Plots were located on a mature stand of creeping bentgrass and were arranged in a randomized complete block design with 3 replications. Each plot measured 5 x 5 ft, for a total of 25 ft² per plot. Bentgrass was a mixed sward of ‘1019’, ‘1020’, and ‘Penncross’ maintained at 0.5”.  Soil at the site was a 1:1:1 mix of sand:peat:soil with a particle size of 13.7% sand, 56.9% silt, and 29.5% clay.  Soil pH was 7.6 with soil P and K contents of 17 and 58 ppm, respectively.  Soil type was a Nicollet clay-loam (fine-loamy, mixed, mesic, Typic Hapluldoll). 

The full list of treatments appears in Table 1.  All products were applied through TeeJet 8002VS nozzles in a spray volume equivalent to 2 gallons/1000 ft² powered by carbon dioxide supplying 40 pounds per square inch. The products were generally applied on 14 day intervals.

Results

The two week interval of application was too long to get satisfactory control of dollar spot with chlorothalonil (Table 2). The addition of the KA-9107 to chlorothalonil did provide numerically better control in most data collection dates.  These differences were significant on Sept. 2, Sept. 24, Oct. 2 and for the grand mean of all dates.   Fathom 14.3 MEC, Briskway, and Renown also provided less than desirable control. Control with Briskway was improved by KA-9107 on July 8 and July 27, as was the control with Renown.  The control with Fathom 14.3 MEC was improved by the adjuvant on August 25.  Emerald, Secure, and Velista were the most effective controls of dollar spot.   While at most dates, there was a numerical advantage to adding KA-9107 to these materials, there control was so effective, that none of these differences were significant.

Overall means comparing fungicides with adjuvant and those without adjuvant were calculated and orthogonal contrasts were performed to compare the means (Table 2) (Figure 1).  Significant improvement in activity of all fungicides that included KA-9107 were observed on July 8 and July 27.   The grand mean of all treatments over all dates showed a decrease of from 22 % dollar spot to 18 % dollar spot when KA-9107 was used as an additive.  The level of significance for this difference was 0.08.

It is apparent that KA-9107 can boost the activity of some fungicides for the control of dollar spot on creeping bentgrass turf.  Future studies could include the application of KA-9107 without a fungicide to determine if it provides any suppression on dollar spot development by itself.  It would also make sense to test the most effective materials with and without the adjuvant at longer intervals between treatments to determine if KA-9107 extends the activity of these products.

Table 1.  Treatments in the 2015 Kalo Fungicide/Adjuvant trial.
				Product	Adjuvant	Product	Adjuvant	App
Trt #	Treatment	Rate (/1,000 ft²)	Rate (/1,000 ft²)	Rate (ml/25 ft²)	Rate (ml/25 ft²)	Interval
1	Control			-	-	-	-
2	Chlorothalonil			1.8 dry oz.	-	1.277 g	-	14 days
3	Chlorothalonil + adj			1.8 dry oz.	1.3 fl. oz.	1.277 g	0.96 ml	14 days
4	Emerald			0.13 dry oz.	-	0.092 g	-	14 days
5	Emerald + adj			0.13 dry oz.	1.3 fl. oz.	0.092 g	0.96 ml	14 days
6	Secure (Fluazinam)			0.5 fl. oz.	-	0.37 ml	-	14 days
7	Secure + adj			0.5 fl. oz.	1.3 fl. oz.	0.37 ml	0.96 ml	14 days
8	Fathom 14.3 MEC (propinozole)			0.5 fl. oz.	-	0.37 ml	-	14 days
9	(Fathom 14.3 MEC  + adj			0.5 fl. oz.	1.3 fl. oz.	0.37 ml	0.96 ml	14 days
10	Briskway (difenoconozole +     azoxystrogin)			0.5 fl. oz.	-	0.37 ml	-	14 days
11	Briskway + adj			0.5 fl. oz.	1.3 fl. oz.	0.37 ml	0.96 ml	14 days
12	Renown (chlorothalonil + azoxystrobin			4.0 fl. oz.	-	2.96 ml	-	14 days
13	Renown + adj			4.0 fl. oz.	1.3 fl. oz.	2.96 ml	0.96 ml	14 days
14	Velista (penthiopyrad)			0.5 dry oz.		0.355 g		14 days
15	Velista + adj			0.5 dry oz.	1.3 fl. oz.	0.355	0.96 ml	14 days

Table 2.  Data from 2015 Dollar Spot Trial.
	% DOLLAR SPOT INFESTATION
TREATMENT	8-Jul	22-Jul	27-Jul	8-Aug	14-Aug	25-Aug	2-Sep	24-Sep	2-Oct	MEAN
1.  Control	68	68	85	49	38	32	19	42	24	47
2. Chlorothalonil	25	57	75	54	52	83	82	33	15	53
3. Chlorthalonil + adj	13	52	70	30	37	73	75	15	6	41
4. Emerald	1	6	1	0	0	3	11	4	2	3
5. Emerald + adjuvant	0	2	0	1	1	0	3	1	1	1
6. Secure	0	1	1	1	2	6	13	3	0	3
7. Secure + adjuvant	0	1	2	2	0	4	9	4	0	2
8. Fathom 14.3 MEC	8	38	28	12	12	53	70	27	9	29
9. Fathom + adjuvant	3	32	21	6	6	29	67	24	10	22
10. Briskway	28	57	29	12	7	27	84	15	3	29
11. Briskway + adjuvant	11	37	10	4	4	25	77	18	5	21
12. Renown	33	53	64	14	8	45	72	14	6	34
13. Renown + adjuvant	14	52	52	24	15	60	83	30	6	37
14. Velista	0	5	4	2	1	5	12	6	4	4
15. Velista + adjuvant	0	2	1	1	0	2	7	5	1	2
LSD 0.05	16	21	12	24	26	16	10	15	8	12
ADJ VS NOADJ	0.02*	0.15	0.01**	0.37	0.57	0.16	0.10	0.77	0.34	0.08
MEAN ADJ	6	25	22	10	9	28	46	14	4	18
MEAN NOADJ	14	31	29	14	12	32	49	15	6	22