UPDATE ON BERMUDAGRASS AT DOWLING HIGH SCHOOL IN DES MOINES

Nick Christians
October 24, 2013

One of the big changes going on in the Upper Midwest turf industry is the increase in Bermudagrass (Cynodon dactylon).  This warm-season grass was not a problem in past years because it would winter kill each year.  In fact, I tried several times unsuccessfully to grow it here, with the exception of the steam lines on campus. Even in the most protected areas around campus, it would not survive the winter..  Now, we are seeing it in lawns and sports fields and it has been surviving because of the milder winters of the last couple of years..

I have not had any reports from golf courses.  If any of you working in golf are seeing it, send me some pictures.

The following pictures are from Eric VanGinkel of the Iowa Cubs.  Eric is also working on the Dowling High School baseball field.  The baseball field has the most Bermudagrass in it of any field that I know of in central Iowa.  The Bermuda is just going dormant and will be completely dormant in a couple of weeks.  I'll try to get some followup pictures at that time.

These pictures are from Oct. 23, 2013.  In the first one, you can just pick out the Bermudagrass as is begins to go off color.

Notice the long stolons spreading out over the track.

It will be interesting to see what happens if we get a normal, cold winter this year.

"Creeping Charlie" (Glechoma hederacea) control

Ryan Adams
10/22/2013

Ground Ivy, or “Creeping Charlie” is probably the most difficult perennial broadleaf weed to control in Iowa. It is an excellent indicator of compacted and poorly drained soils. Ground ivy reproduces by seed and also by rooting on its creeping stems. It was first introduced to the United States as a ground cover alternative in shaded areas. However, its extensive runners (up to 5-10 ft. long) not only began out-competing lawn grasses in the shade, but it quick spread rapidly into full sun.

Ground Ivy is easy to identify with its distinct square and prostrating stems, which readily root at the nodes (as seen to the right from the Scotts grass manual).  The leaves are round to kidney-shaped; borne on a short petiole.  When crushed or mowed the leaves give off an aromatic minty odor.  This aromatic odor often characterizes the Lamiaceae or “mint family” and contains many household cooking spices such as basil, rosemary, and peppermint. Ground Ivy has bright green leaves on an opposite leaf arrangement. The bluish-purple, trumpet-shaped flowers usually appear in May. 

The best time to treat ground ivy with postemergence herbicides is when it is translocating carbohydrates deep underground in the late fall and maybe even as late/after the first frost. The late fall application will not yield visible results until the spring. Repeated applications and persistence over multiple seasons may be required for complete control. Even with complete control there is a strong possibility it will move back in rapidly from a surrounding area. A combination of postemergence herbicides containing 2,4-D, dicamba, MCPP and triclopyr provides the best potential control. Below you will find a few additional pictures.

KENTUCKY BLUEGRASS REGROWTH FROM RHIZOMES

Nick Christians
October 17, 2013

The recovery of Kentucky bluegrass following this summers drought has been amazing.  Most areas that were completely dormant in September have now recovered.  The reason for this is the rhizome system of this amazing lawn species.  The picture below shows this underground stem system and how it grows from the plant.  The rhizome is a stem and not a root.  It has buds on every node and every bud is a reproductive structure.   These buds are protected underground and can remain inactive for months.  When they are needed for the survival of the plant, the will begin to grow and form new crowns.

 Here is one of my pictures of the rhizome system on Kentucky bluegrass.  It has been estimated that one Kentucky bluegrass plant can produce as many as 1300 daughter plants in a single season, mostly from the rhizome system.

 Here are some interesting pictures that I took at the research station late in the summer and through the fall showing the ability of Kentucky bluegrass to recover.  The first picture shows an area around an irrigation repair where plywood was left on the Kentucky bluegrass turf long enough to kill all of the plants above ground.  It looks dead.

Here is a picture taken a couple of weeks later.  Notice how some green is beginning to appear.  That is regrowth from the underground stem system.

Approximately 4 weeks after the plywood was removed, the area is showing considerable improvement without any reseeding.

 This picture was taken in October.  It shows almost complete recovery.  This is the same type of recovery that we are seeing from drought affected areas this fall.  It is one of the main reasons that we use Kentucky bluegrass the way that we do in turf industry.

The importance of high-quality seed

Ryan Adams

10/10/2013

Turfgrass establishment from seed can be a challenging endeavor. One key to successful establishment is the use of high-quality seed that is best adapted to each individual site. In the turfgrass industry, there are mixtures and blends of seed. A mixture is a combination of multiple species, while a blend is a combination of cultivars within the same species. For example, Kentucky bluegrass and perennial ryegrass in the same bag of seed would be a mixture of seed. However, a blend is a combination of cultivars of the same species such as Midnight and America Kentucky bluegrass. 

Seed Labeling Information

In most cases, the seed label is the best source of information pertaining to seed quality. By law, each seed package sold in the US must be labeled truthfully. However, labeling does have its downfalls and all consumers must be aware of the potential loopholes. There are no bargains when it comes to turfgrass seed. For a higher quality seed, you will have to spend a few more dollars. The availability of high-quality seed is limited and ultimately expensive to produce, which has led to the production of poor-quality seed.

The germination percentage should also be considered when purchasing seed. Seed should never have labeled germination rate below 85%. In addition to the labeled germination rate, time also play a huge factor in germination percentage. Seed germination decreases over time and germination rates may have decreased significantly since the original testing date. 

The percentage of inert matter tells you the weight of all nonseed material in the bag. Weed seed percentage is very important and is the total weight of all the weeds. In most cases, noxious weeds are of little concern in turfgrass because of the continuous mowing and defoliation following germination. Quackgrass is one of the few exceptions. 

The biggest loophole and seed contamination occurs in the percentage by weight of other crop seeds. Most of the worst weeds in turf are perennial grasses. Most of these perennial grasses are produced commercially, which group them into the other crop seed category rather than noxious weeds. Grasses such as bromegrass and tall fescue are particular problems. The species list of “other crops” is not usually listed on the label and it is hard to identify their potential impact in turfgrass seeding. To prevent issues you should always use high-quality seed from a reputable dealer. There are no bargains in seed and it is advisable to pay more now because it will save you money and headaches in the long-run. 

One example of this can be seen below with a yard contaminated with common perennial ryegrass. Common perennial ryegrass is usually found in cheaper seed mixes. It is produced at a lower cost than many of your elite perennial ryegrass cultivars. The common perennial ryegrass can be unsightly and drastically reduce turf quality. It has many of the same identification characteristics that you would consider a more desirable perennial ryegrass to have. Folded vernation (once closely observed from a microscope), short to midsized auricles possible, bunch type growth, potential red stem base (is absent in pictures below), divided collar, and a pointed leaf blade that rolls out of the sheath. Common perennial ryegrass however lacks the allure features of the more elite perennial ryegrass cultivars. It often grows awry and is perceived as a nuisance and weed species as seen in the pictures below.