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My Take on the "Dandelion King"

May 6, 2010

I urge you to read Marcus’ blog posting from Wednesday, April 28th. The post refers to an article from the NY Times and a person self dubbed the ‘Dandelion King.’ I find his statement that the war on weeds isn’t “winnable at a morally acceptable cost” is based on his opinion rather than any actual knowledge of turfgrasses or turfgrass management. See the complete article by clicking here.

I believe everyone in our industry should heed Marcus’ advice, “Equip yourself with this knowledge so you can provide an insightful answer next time you are challenged about the benefits of turfgrass.” The Wednesday April 28th blog article from Marcus contains excellent ‘equipment’ for that answer.

Again and again I observe the most ‘interesting’ writers getting their blather printed as fact because they are able to editorialize with word choices and interesting adjectives. For example, the so called ‘Dandelion King’ states; “I soon learned that the carpets of green in suburbia are the product of assiduously applied chemicals…” The word assiduous sounds very sinister here but the definition is benign:

I am certain the author meant ‘constant in application’ but the truth we know is that diligent is a better definition.

What the author obviously does not understand is that good management can lead to good turfgrass quality without an abundance of inputs. He just ‘doesn’t have time to figure this stuff out,’ so he has developed an ‘environmental excuse’ for his poor skills. Take a look at Marcus’ scientific response and help this author and others like him realize that there is nothing insidious about proper turfgrass management. It does take a little work and knowledge, but the environment will benefit from that knowledge and effort.

I won’t go on bashing this author about the other misrepresentations in his article, except to say that his ‘multiple’ applications of pre emergent are senseless and the subsequent post emergent applications he so despises have little to do with the success or failure of the preemerge. So it goes.

Suffice it to say the author has done just enough ‘Googling’ to be dangerously misinformed. Atrazine is a grass killer, let’s not lump it in as a ‘lawn chemical.’ Please.

Bottom line is simple, we either educate those that think like the ‘Dandelion King’ or we let the self proclaimed ‘environmentalists’ screw up things beyond belief.

Jeff Wendel
Executive Director
Iowa Turfgrass Institute


Smooth and Downy Brome Identification and Control

April 25, 2014

In the early spring before Kentucky bluegrass breaks dormancy and after Kentucky bluegrass shut down for the season in the fall, smooth brome stands out as a course textured patch in your lawn, sod farm, golf course rough, or sports field. During the growing season, its color and texture are comparable to Kentucky bluegrass and is not as much of a nuisance.  

Both brome species (Smooth and Downy) can act as weeds in high quality turf areas. Smooth brome has many desirable characteristics to function as a useful turfgrass species; however, its poor density limits the use to low-maintenance areas. 

There are several identification traits distinguishing brome grass from many other weeds. The sheath is nearly closed, giving it a V-neck sweater appearance. Brome has a rolled vernation, hairy sheaths and blades as well as a distinctive “watermark” (or W-shaped) on its leaves as seen below in Photo 1.  Its spindly-natured leaves, small membranous ligule, and winter annual growth habit can usually identify Downy brome. Brome spreads rapidly by its extension rhizome system and its seeds are often carried by wind/birds from low maintenance areas to well-maintained turf. 


There is no guaranteed selective control for Smooth brome in Kentucky bluegrass, creeping bentgrass, or perennial ryegrass turf. Early research from Zac Reicher and Matt Sousek at the University of Nebraska has shown earlier year application (June) rather than (July) will aid in Tenacity control of smooth brome in Kentucky bluegrass. This study will be replicated in 2014 and further data will be passed along as available. Downy brome can be controlled with the preemergence herbicide Siduron and post-emergent Sethoxydim (only for use in established fine fescue stands; tall fescue slightly tolerant).

In most cases, a nonselective, systemic herbicide should be used and multiple applications may be needed to effectively control brome grass. 

Photo 1: Smooth bromegrass’s v-neck sheath and “w-shaped” watermark at midway point of leaf blade. Photo courtesy of Stephen K. Barnhart, Iowa State Press (1997). 

Photo 2. Picture of Downy brome taken this week at the ISU research station. You can see the v-neck sheath as well as fine hairs.



May 27, 2014

Quackgrass (Elymus repens) is the hardest turf weed to control that I know of.  You can identify it by the long clasping auricles on its collar (Fig. 1) and by its extensive rhizome system (Fig. 2).  I get the question occasionally whether the new herbicide Tenacity (mesotrione) will selectively control this species.  The answer is “no”.

Figure 1. Auricles

 Figure 2.  Rhizomes

We just treated the Kentucky bluegrass (Poa pratensis) turf at the research station shown in Figure 3.  The result is that the quackgrass turns white, as can be seen in the picture.  That always gets peoples hopes up, including mine when I first started working with this product.  Unfortunately, the quackgrass always recovers and comes back as bad as ever.  Repeat applications do not work either.  I tried for 4 seasons to kill patches in my own lawn, hoping that my tenacious applications of Tenacity would kill it.  I lost, and the quackgrass was not even reduced in severity by my repeated applications.

Figure 3. Quackgrass turned white by Tenacity.

The only way to control it remains non-selective applications of Roundup (glyphosate).  The rhizomes are very hard to kill and repeated applications of Roundup will be necessary.  If you have this problem and want to get rid of the quackgrass, start now in May by killing the infested areas.  Then repeat apply every time the quackgrass comes back from rhizomes.  You should set a goal of reseeding in mid-August.  

Even a better solution would be to sod over the dead areas.  The rhizomes have a harder time emerging through sod than they do into a newly seeded area.



July 22, 2009

Congratulations to Rick Tegtmeier. This is Windmillgrass (Chloris verticillata).
When the seed head separates from the plant in the fall, it rolls like a tumbleweed and spreads its seed over the landscape. It has been present in central Iowa for only a few years. It is a warm season that is damaged by cold winters and was generally found in Missouri and south until recently. It is often seen along the curbs of streets and other compacted areas.


This is a relatively new arrival in central and northern Iowa. It is a perennial warm-season grass that forms an expanded panicle seed head late in the summer. It is generally found in dryer compacted areas. Any guesses?




July 9, 2009

I found this rather unusual weed in a lawn on July 9, 2009 (the picture on the bottom). I also found the same species on campus last year (picture on the top). It is unusual for this area. Post your guess as to what it is in the comment section. The answer will follow in a couple of days.


Congratulations to Nick Dunlap for figuring this one out.

It is Yellow Rocket (Barbaria vulgaris), part of the mustard family. It was quite common in Ohio when I was there many years ago, but I just began seeing it three years ago in Iowa. Since then, I have seen a number of them in central Iowa turf. It is not hard to control, similar to dandelion.


Speedwell in Des Moines in Bloom

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 in Des Moines

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

Speedwell on Campus

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.