1) Large patch; 2) Economic and aesthetic comparison of turf management; 3) Mystery zone of turf death

Hello,

I have a few unrelated things today: large patch, a guest blog about different management systems, and then a turfgrass mystery.

First, I'll just mention quickly that as our zoysia grass is greening up, large patch is firing. We have had some heavy rains over the past 2 days so the fungus will be happily growing. Here is some large patch in our research plots:



Second, here is a guest post by my colleague Dr. Cale Bigelow at Purdue University. I must admit that Cale and I were both sorely tempted to post on Monday in order to get the honorable Dr. Kaminski all riled up, but then I opted to just post it today. Watch out, though, John...

Cale was part of a study that compared the economics and turf quality aspects of four different management systems. While this study was focused on a home lawn type of environment I think those in the golf course world will find it interesting, too.

Comparing Cool-season Lawn Fertilizer and Pesticide Programs: Aesthetic and Economic Trade-offs

Guest post by Cale Bigelow

There is increasing public interest in alternatives to traditional cool-season lawn fertilizer and pesticide application programs. Historically these programs have been based on calendar driven fertilization and the attitude toward pesticide applications has been a prophylactic approach for controlling broadleaf and annual grassy weeds as well as insects like white grubs. As consumer attitudes toward the perception of a “perfect lawn” begin to change, alternative management methods that involve more judicious pesticide applications and engaging in Integrated Pest Management (IPM) and scouting approaches these practices may become more publicly accepted. Furthermore, there is a very strong interest in “organic” products and approaches to lawn care. Currently, the information regarding longer-term performance of organic products in the field is very limited.

To examine the effects of these potential lawn management alternatives, an interdisciplinary field study was conducted between the Entomology and Agronomy Departments at Purdue University in West Lafayette, IN. Ph.D. student, Victoria Caceres, working with Drs. Doug Richmond, Tim Gibb, Cliff Sadof and Cale Bigelow evaluated four disparate lawn management programs which were: a traditional calendar driven consumer program (CP), a natural organic program (NOP), an integrated pest management/scouting program (IPM) and all were compared to a no input program (NIP). All programs with the exception of the NIP received approximately 3 # N/1000 ft2 annually with the NOP relying on manure-based fertilizers, corn gluten and entomopathogenic nematodes for annual grassy weed and insect control, respectively. The IPM program used traditional products but pesticides were only applied when warranted or thresholds were met. The turf was in full sun, maintained at 3 inches and irrigated only to prevent severe stress and facilitate product applications. The plots were regularly assessed for appearance, greenness, and periodic growth. Individual program maintenance costs were calculated based on product cost and estimated labor costs for product applications/scouting.

Study results:
While there were seasonal differences for appearance, all programs except the NIP program provided a satisfactory appearance and green color that would be suitable to most homeowners. While the NOP was sufficiently green there were significantly more broadleaf weeds in this program, which detracted from overall appearance. This result emphasizes the need to develop effective natural organic products for broadleaf weed management. Additionally, the economic benefits of scouting were demonstrated in the IPM program (Table 1) and illustrates a potential reduction in unnecessary pesticide applications and reduced input costs.

It is important to note that these results are observations over only two growing seasons and the long-term implications of this study should be carefully considered. For example, it is possible that some weed or insect pests could become problematic, canopy greenness/turf density could decline in time and the overall appearance may be objectionable to some consumers. Nonetheless, this study provides the framework for future studies and may begin to allow lawncare professionals an opportunity to consider the possibility of providing an IPM/scouting service to clients that desire this management approach. It should, however, be noted that these consumers should also be willing to accept a less than perfect lawn at certain times through the growing season.

The photo shows a visual comparison of the 4 management systems.

For a more detailed description of this study it can be found in: HortTechnology 20:418-426. Caceres et al., 2010. Aesthetic and economic impacts associated with four different cool-season lawn fertility and pesticide programs.

Table 1. Comparative product and estimated labor costs for four disparate cool-season lawn management programs over two growing seasons.

Management program..................... Cost* ($/A)

1. Consumer/calendar driven ............... 2,743.00
2. IPM/scouting .................................. 1,989.00
3. Natural organic ............................... 3,498.00
4. No input ........................................... 0.00

*Note this value is for two growing seasons and does not include mowing costs.



And, finally, here is a turf mystery to solve:



I know it's another home lawn, not golf course, but spills can happen anywhere. This certainly looks like a spill, eh? The top part (the totally dead zone) occurred last fall, and then this spring it started moving out (downhill).

The first thing that came to my mind was a spill of herbicide, fertilizer, or de-icing salt but the client insisted that this did not happen. Of course, people do forget, and they do not always know what other members of the household (or golf course) have been up to! But, what are some other possibilities? Well, notice that the damage is right by the front door. It is easy to imagine that someone may have worked with a household cleaning chemical, a paint thinner, etc and then dumped the bucket outside. Or, they deep-fried a turkey on the front patio at Thanksgiving and then dumped the grease. Or, they spilled lawnmower gas. Or, Clifford the Big Red Dog is real.

There are plenty of scenarios you could imagine where something got spilled or dumped but at the time it did not seem like something that would cause a problem.

If YOU have a crazy idea on what caused this, leave a comment. Maybe I'll have a prize for the best story!