Wednesday, November 30, 2011


Nick Christians

For the first time ever, I will be offering Hort/Agronomy 351-Turfgrass Establishment and Management- in the spring. It will be entirely web based and you can take it any place in the world without coming to campus. For more information, see

This course carries minor graduate credit and could be used towards an MS degree.

I have recently become part of the Master of Agronomy Distance program. Through this web based program, you can get an MS in agronomy with a specialization in Turf Science while you are employed full time. Most of it is offered off-campus through the web. You would need to do a creative component in some aspect of turf science and come to campus for a couple of short summer workshops and for your final defense.

This program is ideal for those who want to achieve a Master's degree without leaving their full time job. It is well suited for those teaching in two-year programs who want to finish a master's degree. The creative component can be the development of a course for teaching at the community college level.

For more information on the Master of Agronomy program, see:

Pass this on to anyone who might be interested.

I can be reached at 515-294-0036 for more information, or e-mail me at

Sunday, November 13, 2011

It’s Beginning to Look a Lot Like Christmas

Many parts of the state received their first snowfall last week. The days are shorter and 4” soil temperatures are slipping from the low 40’s into the high 30’s. Most trees have lost the majority of their leaves. Long-establishing creeping bentgrass greens display a spectrum of purple patches. Everywhere you look, there are signs that another growing season is coming to an end. But irrigation winterization may best signify that the growing season is over and winter is just around the corner.

Irrigation winterization is the process of evacuating water from the irrigation pipes to avoid damage from freezing temperatures. While a portion of the water can be evacuated at dead ends and low points of the piping through manual and automatic drain valves, larger irrigation systems also “blowout” the piping system using compressed air. This method of winterization can be very damaging to the piping system and dangerous to workers if proper safety procedures are not followed.

I was reminded of the hazards that can occur during the winterization procedure when I received the picture below from a former student. In this scenario an individual head would not activate from the satellite box and the employee went to flag on the head. When the head activated, the internal assembly broke free from the bucket striking the worker under the chin.

Irrigation winterization can be dangerous and safety precautions need to be taken to avoid injury.

This post will outline some of the basic safety measures that should be followed to avoid personal injury and undue stress on the irrigation system.

Use a safety harness to tether the air hose to the compressor. Air hoses connect to the compressor though a claw or similar type coupling. The connection is usually secured with cotter pins or wire but also consider using a safety harness. The harness will prevent the hose from flailing about in the event the connection fails while under pressure.

A harness that connects the air hose to the compressor provides additional safety in case the connection fails when under pressure.

Do not force air through the backflow preventer. Be sure to hookup after the backflow preventer as forcing air through this component can cause damage. First, blowout the system, then allow the backflow preventer to drain.

Regulate the air pressure with a pressure regulator. Even though larger irrigation system may operate with water pressures in excess of 100 psi, air pressures of this magnitude can damage the system. Use of a pressure regulating valve can help prevent over-pressurization. Most manufacturers recommend air pressures around 50 psi.

A pressure regulator can help prevent excessively high pressures from damaging valves, pipes, and irrigation heads.

Do not stand directly over irrigation components when under pressure. Air is less viscous compared to water and can generate greater stress under comparable pressures. Weak points in the irrigation system can fail under air pressure. Protect yourself from personal injury by staying clear of irrigation components when under pressure. It’s also a good idea to wear proper eye and ear protection during the winterization process.

Do not work on a sprinkler head while under pressure. If a head sticks on or won’t activate automatically or manually valve the section off and bleed the pressure through a quick coupler. Once the air stops at the quick coupler the head is safe to work on.

Evacuate water ahead of time. Before activating individual sprinkler heads use drain valves and quick couplers to initially evacuate water. This will reduce the amount of water in the system and can shorten the time needed to evacuate air through sprinkler heads. Less air moving through valves and sprinkler components and will help cut down on wear and tear.

Quick couplers and manual drain valves can be used to drain water before evacuating water through sprinkler heads.

Do not allow sprinkler heads to run for prolonged periods of time. Sprinkler drive mechanisms are normally lubricated as the water moves through the internal assembly. In the absence of water, heat caused from friction can damage these plastic components. Cycle between one or more stations to avoid excess buildup of heat.

Taking care to follow these safety procedures can help the winterization process go smoothly while minimizing damage to the irrigation system and preventing personal injury.

Hoping you have successful (and safe) winterizations!

Marcus Jones
Assistant Scientist

Wednesday, November 9, 2011


Nick Christians
Nov. 11, 2011

Here is the next installment in the series on 'answer line person' Richard Jauron's experience with the control of nimblewill with Tenacity (mesotrione). You will find other installments from this summer and fall.

We're going to follow this until well into next year when we know how successful this has been.


Here is a short chronology of my experience treating nimblewill infested areas in the lawn with the herbicide Tenacity (Mesotrione). (Previous blogs on this topic were posted on July 7, 2011 and August 2, 2011.)

On Tuesday, June 28, 2011, I treated nimblewill infested areas in my lawn with Tenacity. (One-fourth teaspoon of Tenacity and three-fourths teaspoon of a non-ionic surfactant (Turbo Spreader Sticker) was added to 2 quarts of water.)

Within 2 or 3 days, the nimblewill foliage turned light green. Within 7 to 10 days, the uppermost growth turned white. (See photos 1 and 2)

At the end of 3 weeks, the lowest portions of the nimblewill were still green. Most of the upper portions of the nimblewill were white or brown. (See photos 3 and 4)

The nimblewill was treated a second time on Tuesday, July 26, 2011. (One-fourth teaspoon of Tenacity and three-fourths teaspoon of a non-ionic surfactant was added to 2 quarts of water.)

By late summer, the Tenacity treated nimblewill had turned completely brown and appeared to be dead. The following photographs were taken on September 15, 2011. (See photos 5 and 6). While the nimblewill appears to be dead, the effectiveness of Tenacity won’t be known until late spring/early summer of 2012. If any of the nimblewill has survived, it should begin to green up in late May or June.

Fig. 1

Fig. 2

Fig. 3

Fig. 4

Fig. 5

Fig. 6

Monday, November 7, 2011


Nick Christians
Nov. 7, 2011

As part of the new greenhouse construction project at the horticulture building, the department received a large mural painting on the history of horticulture at Iowa State. It completely surrounds the atrium area by the main office.

They included the turf bowl trophy in the painting. So, while we have to return the traveling trophy at the next GCSAA meetings in Las Vegas, it will be enshrined forever in the painting.

We, of course, do have the chance to win it back next year. As many of you know, Iowa State has won it 11 or the last 13 years.

The last picture below is on Ed Cott, who was in extension in the department for 35 years. He is pictured with a golf course in the background.

The painting should be finished in a couple of weeks. You are all invited to come by and see it when you get a chance.

Ed Cott pictured with golf course in background.