Quiz Answer Key

Time to check your answers to the quiz.

1) Kentucky bluegrass (Poa pratensis)

2) Annual bluegrass (Poa annua)

3) Bermudagrass (Cynodon dactylon)

4) Mouse-ear chickweed, perennial broadleaf

5) Wild violet, perennial broadleaf

6) Goosegrass, annual grass

7) Perennial ryegrass (Lolium perenne)

8) Tall fescue (Lolium arundinaceum)

9) Bluegrass billbug

10) Japanese beetle

11) Dollar spot

12) Brown patch

It's Finals Week

The blog has fallen silent the past couple of weeks as I am trying to be a responsible student and study for final exams. My students are busy reviewing their irrigation notes and the concepts of static and dynamic pressure, design capacity, matched precipitation rates, water quality and much more. Meanwhile, I am studying (trying to study) for my biochemistry final which is Friday morning. Wish me luck!

So, in honor of finals week, I put together a quiz similar to the one the students take in their introductory turfgrass laboratory. I will post the answers early next week. Good luck, and keep your eyes on your own paper!


Question #1

This grass has a boat-shaped leaf tip and folded vernation. The leaf blade possesses a prominent mid-rib. Growth is rhizomatous.

Name the grass, common and scientific name.






Question #2

This grass also has a boat-shaped leaf tip and folded vernation. There is a prominent mid-rib and a membranous ligule at the base of the leaf. Growth is bunch type.

Name the grass, common and scientific name.






Question #3

This grass has a pointed leaf tip and a folded vernation. There is a tuft of hairs at the base of the leaf blade. Growth is rhizomatous and stoloniferous.

Name the grass, common and scientific name.

Question #4

This weed has small white flowers and the leaves are covered by tiny hairs. This weed can be a problem in golf greens and other closely-mowed turf.

Name the weed and its lifecycle.





Question #5

This weed has heart shaped leaves and white to purple flowers. It can produce rooting stolons and rhizomes.

Name the weed and its lifecycle.

Question #6

This weed has a folded vernation and a zipper-like seedhead. The stems are silver toward the base of the plant.

Name the weed and its lifecycle.







Question #7

This seed lacks an awn. The rachilla is flat in cross section.

Name this seed.









Question #8

This seed has a very short awn. The rachilla is round and flares at the top.

Name this seed.










Question #9

This insect chews into the stem and deposits its eggs. The eggs hatch and the larvae feed on the crown.

Name this insect.







Question #10

This insect hasn't always been a problem in Iowa. Damage can occur to ornamental as well as turfgrass.

Name this insect.







Question #11

The claim is often made that more money is spent on this disease than any other. It is more prevalent under low nitrogen fertility.

Name the disease.







Question #12

This disease appears most often during periods of high air temperatures and humidity. Symptoms appear in a patch and a dark "smoke ring" is often visible. It is more prevalent under high nitrogen fertility

Name the disease.




Marcus Jones
Graduate Research Assistant
Iowa State University

Biochar as a sand-based rootzone amendment

The main objectives of my research focused on the use of biochar as an amendment for sand-based turfgrass rootzones. Currently, peat moss is the most common organic amendment mixed with sand when sand systems are constructed. Peat moss increases water retention and nutrient holding capacity of the sand; however, peat moss is prone to decomposition over a relatively short period of time. Biochar, on the other hand, is very stable in the soil profile, and may prove to be a viable organic amendment for sand-based turfgrass systems. In this study, I used fast pyrolysis switchgrass biochar.

My research objectives were to:
• quantify soil water retention capabilities,
• determine infiltration rates,
• and measure creeping bentgrass rooting depth in sand and biochar rootzones

Results

Soil Water Retention - Biochar significantly increased soil water retention (table below). Plant available water increased as percentage biochar increased.

Infiltration Rates - Biochar significantly reduces infiltration rates (table below).

The table to the right converts the numbers to inches per hour. Six incher per hour is the minimum for USGA guidlines when constructing sand based turfgrass rootzones. Above 10% may be pushing the infiltration rate limit with biochar.

Rooting Depth - The rooting depth of creeping bentgrass was measured by growing ‘T1’ in growth tubes with 30 cm sand and biochar rootzones on top of pea gravel. The tubes were sliced open after 110 days of growth, and the depth of rooting was measured (picture below). This pattern of rooting depth was consistent throughout replications. The far left treatment in the picture is 100% sand, and the far right treatment is 25% biochar; increasing in 5% biochar increments at each treatment level from left to right. Biochar amounts above 10% show inhibitive effects on rooting depth of creeping bentgrass. (Biochar percentages are on volume-to-volume basis).

Conclusions - Biochar increased soil water retention capacity and plant available water, but decreased infiltration rates. Rooting depth of 'T-1' creeping bentgrass is inhibited by biochar above 10% (v/v) levels in the rootzone.

Iowa State Turfgrass is attempting to lead the way in the biochar discussion for the turfgrass industry. We would love to hear any feedback you may have on this topic.

Shane Brockhoff
Iowa State University

What is Biochar?

For the past year and a half, I have been working with biochar for use as a soil amendment for sand-based turfgrass rootzones. Biochar has been gaining a lot of momentum in some agronomy circles as a cure-all soil amendment to improve the sustainability and productivity of our agricultural soils. A flurry of research has been funded and published related to biochar, but what really is this biochar stuff?

In a nutshell, biochar is the co-product of a biofuel production process called fast pyrolysis. Essentially, a biomass feedstock is pyrolyzed, or burnt, at a very high temperature and bio-oil is produced along with biochar. The oil can be used for consumer use after refinement similar to gasoline (see Figure 1). Originally, not much thought was put into using the biochar for any practical use, but agronomy researchers believe there is some potential for its use in agricultural settings.

I will be posting a series of threads relating to biochar in the coming weeks. If you have heard of biochar or have any firsthand experience with biochar or materials similar to it (ie. activated charcoal, fly ash, etc.) please post a reply explaining what your experience or use for these products has been. The reason I ask is because I received a question pertaining to whether biochar will deactivate herbicides, fungicides, ect…

*Illustration borrowered from Johannes Lehmann. Department of Crop and Soil Sciences, College of Agriculture and Life Sciences, Cornell University, Ithaca, NY 14853 (CL273@
cornell.edu) Front Ecol Environ 2007; 5(7): 381–387

Shane Brockhoff
Iowa State University

Irrigation Winterization

If you haven’t already done so, the ritual of irrigation blow out is certainly on everyone’s mind this time of year. This procedure signifies the end of another growing season along with the realization that winter and the accompanying freezing temperatures are probably right around the corner. Properly blowing out an irrigation system ensures that minimal damage will occur during the winter months. Although blow out is a yearly occurrence, there doesn’t seem to be a great deal of literature available about this important procedure. There seems to be various philosophies and most learn from field experience.

One aspect of blow out that has changed over the years is the pressure which the system is blown out. One reason for this change is the fact that sprinkler heads are now primarily comprised of plastic componts compared to their steel predecesors. As a result, the pressure which the system is blown out has been reduced. One way to help reduce the pressure is by using a pressure regulator.

The pressure regulator is usually mounted just off the compressor. The pressure can be monitored and adjusted by a handle on top of the regulator. I have often heard that 50 psi is sufficient to blow out most systems. Obviously, the higher the pressure, the greater the chance of causing damage to the piping system and the sprinkler heads. The other consequence of using higher pressures is coupled to the pressure of the compressor.

Compressors also have a pressure gauge and increasing the pressure of the regulator will decrease the pressure inside the compressor and vice verca. Most compressors should not be operated under 80 psi. Under 80 psi, oil can blow past the seals in the compressor and enter the piping system. Of course you won’t realize this has happened until you charge the system in the spring and oil comes spewing out of sprinkler heads.

Let me know if you have any tips from the field concerning winterization of irrigation systems. Hope everyone has a safe and successful blowout.

Marcus Jones

Graduate Research Assistant

Greetings From Pittsburgh

This week I traveled to Pittsburgh, Pennsylvania to attend the Agronomy Society of America meetings. The meetings are held annually and scientists from all across the world come together to present and talk about their research. I presented on the findings from my germination study that I posted on the blog last week. Part of the conference experience included a tour of Oakmont Country Club and Heinz Field.

Oakmont C.C. was really beautiful and we had a nice day for our tour. The weather in Pittsburgh is slightly cooler compared to our temperatures in Iowa and they receive a bit more rainfall. As a result, they manage annual bluegrass as the primary species on their putting greens. The density of poa is really impressive when it exists as a monostand (picture above). However, they do fight contamination from creeping bentgrass (that seems like a weird statement) and it appears out of place (picture to the right). We also had an opportunity to see the church pues which are much larger in person than I expected (picture at beginning of post).

The second stop on our tour took us to Heinz field. In addition to hosting the Pittsburgh Steelers, Heinz field is also home to the Pitt Panthers. The field is also used for a handful of high school football games and a few miscellaneous events during the year so it receives a good amount of use. The field is Kentucky bluegrass overseeded with perennial ryegrass during the season. The middle portion of the field has a heating system underneath the turf. The field had been overseeded with ryegrass and the heated portion was covered up during our visit to promote germination of the seed and to stimulate growth of the existing turf.

The remainder of the trip was devoted to attending sessions where graduate students and professors present findings from their research. I attached links to abstracts from the talks that I found most interesting and though you might too.

Amicarbazone for Annual Bluegrass Control in Creeping Bentgrass Putting Greens
http://a-c-s.confex.com/crops/2009am/webprogram/Paper55369.html

Potential Use of Mesotrione in Turfgrass Systems
http://a-c-s.confex.com/crops/2009am/webprogram/Paper55382.html

Response of Kentucky Bluegrass Cultivars and Annual Bluegrass Control with Mesotrione at Turfgrass Establishment
http://a-c-s.confex.com/crops/2009am/webprogram/Paper55458.html

Mesotrione as An Herbicide for Spring-Seeded, Cool-Season Turf
http://a-c-s.confex.com/crops/2009am/webprogram/Paper53940.html

Biochar for Sand-Based Rootzone Modification
http://a-c-s.confex.com/crops/2009am/webprogram/Paper53423.html

Dollar Spot Control Using Organic and Synthetic Fungicide Combinations
http://a-c-s.confex.com/crops/2009am/webprogram/Paper55556.html

Anthracnose Severity of Annual Bluegrass Putting Green Turf as Affected by Summer Soluble N-Fertilization
http://a-c-s.confex.com/crops/2009am/webprogram/Paper54138.html

Conversion of Kentucky Bluegrass Rough to No-Mow, Low-Input Grasses
http://a-c-s.confex.com/crops/2009am/webprogram/Paper54254.html

Marcus Jones
Graduate Research Assistant

Golf Course Superintendent – Meadows Country Club

Duties –

Responsible for Golf Course, Clubhouse Lawns, Trees and Flowers, Golf Course Budget, Cart Fleet and Clubhouse Building Maintenance, Purchasing

Qualifications –

2 Year formal Education preferred, Iowa Certified Pesticide Applicator or ability to obtain.

Experience –

Minimum 2 years golf course maintenance experience

Benefits –

State Association Dues, Monthly meeting expenses

Salary Range –

$28,000 -$35,000

Application Deadline –

December 1, 2009

Position Available –

January 15, 2010

Contact Info –

Mark Harris - Board President

Box 299

Moville Ia. 51039

712-873-3184

Email – msharris@netins.net