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Tuesday, July 22, 2014

RUST DISEASE ON PERENNIAL RYEGRASS

Nick Christians
July 22, 2014
nchris@iastate.edu

On July 17, I received an e-mail from Larry Ginger of American Lawn Care with a picture of rust disease showing up on perennial ryegrass, but not on Kentucky bluegrass.  Rust is a fungal disease caused by fungi in the genus Puccinea.

Picture from Larry Ginger showing rust on ryegrass patch in lawn taken July 17.




I had not seen this problem at that time, but yesterday (July 21) I took data on the National Turfgrass Evaluation Program (NTEP) trial at the research station.  I found that many of the cultivars were covered with rust.  I took data on the rust problem this morning (July 22).  I have not seen the problem on the Kentucky bluegrasses as of today, but it clearly a severe outbreak on some of the perennial ryegrasses. Rust often shows up in August on Kentucky bluegrass, perennial ryegrass, and even on tall fesuce (see earlier blogs).  This year it is early and appears to be hitting the ryegrasses first.
 
 Close up of rust on Kentucky bluegrass from last year.


 Rust spores on my shoes after taking data.



 Three pictures of individual ryegrass plots covered with rust on July 22.






 Rust is clearly cultivar specific and there were cultivars covered with it and adjacent plots that were completely free of the disease.  This is another reason for choosing your grass seed carefully.  There is usually a good reason to spend a little more on grass seed.  I have not analyzed the data on which cultivars were affected, but that will be in next year's report.  NTEP does have data available on ryegrass susceptibility to this disease at ntep.org.

Rust is a fungi and there are fungicides that control it, but we generally recommend that you let the disease run its course.  It usually goes away by itself.  You may want to treat on sensitive areas, such as sports fields if it becomes necessary.  

These plots will be on the tour at the turfgrass field day this Thursday, July 24.


Friday, July 18, 2014

IOWA TURFGRASS FIELD DAY JULY 24

Nick Christians
July 18, 2014

The annual turfgrass research field day will be held at the Horticulture Research Station north of Ames, IA on July 24, Thursday of next week.  

We have a number of new things to show this year, including our work on nematodes in a sand-based golf course greens.

For more information, contact Jeff Wendel at the Iowa Turf Office at jeff@iowaturfgrass.org, phone 515-635-0306.  The web site is at http://www.iowaturfgrass.org/itihome.htm.  See the links below for registration and a map to the site.



July 24th - Iowa Turfgrass Field Day - Horticulture Research Station - Ames
Host: Dan Strey
8:00 Registration
8:45 Introductions - Registration Tent
9:00-11:00 Blue and White Tours (see tour schedule here)
10:00-11:00 Red Tour (required for Pesticide Applicator Training)
11:00 Turfgrass Insect, Weed & Disease ID Tour & Phytotoxicity Demo (required for PAT)
12:00 Lunch
Registration Deadline: July 17th. *Onsite Registration available for additional fee*
Registration Fee: $30.00 (includes Lunch)
Registration with Pesticide Applicators Training: $50.00 (includes Lunch)
Call 515-635-0306 with questions or to Register







Wednesday, July 16, 2014

BUFFALOGRASS ROUGH AT ISU GOLF COURSE

Nick Christians
July 16, 2014

On May 28, Dr. Zach Reicher of the University of Nebraska and John Newton, CGCS at the Iowa State University golf course (Veenker Memorial) began a test of buffalograss (Buchloe dactyloides) as a grass for roughs.  Buffalograss is a warm-season species and is generally not used in our region.  Our wet climate generally assures that competing weeds out-compete the buffalograss over time and it is more difficult to maintain than the standard Kentucky bluegrass.

The release of Tenacity (mesotrione) gives us a new tool to fight weeds in buffalograss and the test is designed to determine if buffalograss is a viable option in our climate, if we can keep competing weeds from becoming a problem.  Zach's recommendation on the rate of Teancity is as follows:



Tenacity:
PRE on new seedbeds:  8 oz/A X 2, second app is about 4 weeks after germ maybe earlier if needed. Nonionic surfactant (NIS) in the last app.

POST on new seedlings: 5.3 oz/A X 3, two week intervals. NIS in the last two apps, but probably not the first app just to maximize safety.

POST on established buffalograss: 5.3 oz/A X 3, two week intervals. NIS in all  apps.

The buffalograss was a turf-type variety called "Bowie" (Gr-742).  An area a little larger than an acre between two fairways was killed with Roundup (glphosate) in mid-May.  Three methods of establishment was used.  One third of the area was tilled and seeded at 2 pounds of burs per 1000 sq.ft. The same rate of seed was slice-seeded into another one third and the final area was core aerfied and seeded.  The areas were irrigated until the seed germinated.  Tenacity was applied the week of June 9 and again on June 20.  We will continue to monitor the area for the next couple of years and keep you posted as to how it is working.

John and Zach on the day of seeding, May 28, 2014














 Areified area was seeded with a drop seeder.