1997 Tbrfgrass Field Day Golf I\irf Tour Map

Transcription

1 1997 Tbrfgrass Field Day Golf I\irf Tour Map

2 Bioject Update J.F. Powell, A.R. Detweiler, N.M. Dykema, and J.M. Vargas Jr. Department of Botany and Plant Pathology Considerable research has been directed toward biological controls due to public concerns of pesticide safety, environmental concerns, loss of chemicals due to reregistration, and loss of chemicals due to resistance development. The important thing to remember when dealing with biological controls is that it requires the use of live organisms. Unlike chemical pesticides, live organisms require certain conditions to remain alive and have much shorter shelf lives than chemical pesticides. Biological control is the use of one organism to manage the population of a pest or pathogen. Many of these biological control agents are naturally found in the environment, but at insufficient levels to provide significant disease management To provide adequate disease management, it is necessary to increase the numbers of these organisms to reach a population threshold which provides acceptable disease management through direct application of the biological control agent However, following application, the populations of these organisms generally decline due to their inability to colonize the given environment, competition with other organisms, and mortality due to environmental factors such as UV light and insufficient moisture. In order to maintain population levels of a biological control organism required to provide disease management, it is often necessary to apply the biological control agent frequently. The BioJect System (EcoSoil Systems, San Diego, CA) is a recent technology that has been developed to help overcome some of the current shortfalls of biological control agents. This system allows the superintendent to grow the bacterial biological control agent on a daily basis. The process of growing the bacteria is automated within the BioJect which injects water, a nutrient solution, and bacterial inoculum into the culture vessel. The bacteria are grown for a period of time under constant aeration and mixing allowing them to grow and multiply. Following this incubation period, the bacteria are injected into the irrigation system and applied with the nightly watering. This process can be performed on a daily basis to maintain populations of the biological control agent in the field.

3 Precision Turfgrass Management - Getting Started Beau McSparin, Geoff Rinehart, James Baird Department of Crop and Soil Sciences Precision Turfgrass Management (PTM) is a new approach that will allow turf managers to better evaluate and treat the natural variability that exists throughout their turf site. Variability can be caused by many factors including soil type, fertility, plant species, disease, and moisture status. Determining which properties are responsible for variability in turf is a difficult task and a challenge to IPM technology. PTM is comprised of four main components. The Global Positioning Satellites (GPS), first designed by the U.S. Department of Defense as a military navigation system, uses satellites to determine accurate, real-time positioning in space. Global Information Systems (GIS) provide user-friendly software to organize GPS data into a mapping format This information can be mapped into layers of information to analyze a variety of turf conditions over time. GIS is the same system used by cartographers to create highly accurate maps. Sensors can be used to detect variability in turf. For example, sensors have been developed to detect variability in plants based on the type or intensity of specific wavelengths of light that are reflected from the canopy. Finally, Variable Rate Technology (VRT) provides the application of pesticides or fertilizer at specific rates and locations depending upon the needs of the plant The combination of GPS, GIS, sensors, and VRT will allow turfgrass professionals to manage their turf according to specific needs of a location, thereby reducing excessive and unnecessary application of pesticide and nutrients, and potential harm to the environment Michigan State University is currently working on a research project in cooperation with the Toro Company to gain a better understanding of factors that cause variability in turf and to develop methods to accurately sense variability in turf as a part of PTM.

4 Ataenius Update Nikki Rothwell and Dave Smitley Department of Entomology Ataenius spretulus, commonly known as the black turfgrass ataenius was investigated in a mowing experiment on a perennial ryegrass golf course for the second year. In 1995, we erased the old fairway/rough interface and replaced it with a new border (Figure 1). We believed that the mowing height may determine where ataenius populations are located. We also believed that the predators and the milky spore disease which naturally control ataenius grubs are influenced by mowing height In 1996, we found that ataenius grubs were most prevalent in plots of turf that were mowed to fairway height in 1995, regardless of how it was mowed in In 1997, we found twice as many grubs in the fairway-mowed turf compared with the rough-mowed turf. From this research, we can conclude that ataenius grubs are found more often in shorter mowed turf. Golf course fairways will often have more ataenius grubs because of the height of the grass, regardless of fertilization, irrigation, cultivation, and fungicide applications. Predators (rove beetles and ground beetles) and milky spore disease were again monitored this summer. Predators were more prevalent in rough-mowed turf. There seems to be an inverse relationship between predators and ataenius grubs, as the number of predators increases, the number of ataenius grubs decreases. All grubs collected from our plots were also monitored for milky spore disease. We found 68% of the grubs in the rough were infected with milky spore disease while only 34% of the grubs in the rough were infected. From these results, we can verify that mowing height plays a role in predator populations and infection levels of milky spore disease. Ant trapping was also done this summer. Entomologists at Purdue University have found a thief ant that is known to consume Japanese beetle eggs. We did not find enough of these ants to suspect any impact on ataenius populations. In the future, we will be investigating why fewer predators and less milky spore disease are found in the shorter-mowed turf. A very big thank you to Doug Palm and Chuck at Cattails Golf Club.

5 Figure and 1996 mowing regime along rough/fairway interface on a perennial ryegrass golf course. Numbers 1-4 indicate sites for pitfall traps and soil cores per plot. Rough Rough 1995/Fairway 1996/Fairway 1997 Fairway 1996 Interface 1995 Interface Fairway 1995/Fairway 1996/Fairway 1997 Rough 1995/Rough 1996/Rough 1997 Fairway 1995/Rough 1996/Rough 1997

6 New Approaches to Nitrogen Fertilization of Turfgrass Douglas E. Karcher Department of Crop and Soil Sciences Nitrogen fertilization is a cultural practice essential in maintaining high quality turfgrass areas. Nitrogen nutrition is directly related to turfgrass color, shoot and root growth, shoot density, disease susceptibility, and drought tolerance. Because of nitrogen's vital role in plant nutrition, methods of improving application efficiency in traditional crops has been studied extensively. Greater yields have been achieved with many crop species as the result of incorporating nitrogen fertilizer into the soil. Traditionally, there has been no equipment available to the turf manager to incorporate nitrogen fertilizer into the soil without causing considerable surface disruption and it has therefore been applied almost exclusively to the turfgrass surface. High pressure water injection was introduced early this decade as a method of cultivating turfgrass areas while causing minimal surface disruption. The Toro HydroJect, the original water injection cultivation unit, utilizes 5000 psi water bursts to cultivate soils to depths reaching 4 to 6 inches. This technology has created the possibility of incorporating nitrogen into turfgrass soils by injecting soluble fertilizer. Preliminary studies conducted at Michigan State University concluded that injecting nitrogen with the HydroJect increased clipping yields, produced darker colored turf, increased nitrogen content is leaf tissues, and decreased moisture stress symptoms when compared to surface applications of nitrogen. It was not possible to determine whether these benefits of injecting nitrogen were the result of placing nitrogen deeper in the soil profile, the result of creating aeration channels with the high pressure water jets, or a combination of deeper nitrogen placement and aeration channels. Two research projects were initiated this year at the Hancock Turfgrass Research Center to study the mechanisms involved with the beneficial turfgrass responses related to nitrogen injection. The objective of Study #1 is to examine the interaction between deep nitrogen placement and aeration channels created by the HydroJect. The objective of Study #2 is to examine the differences in nitrogen uptake between surface and subsurface applications with regard to amount and duration of fertilizer nitrogen incorporated into turfgrass tissues. STUDY #1. "Nitrogen Application Depth and Water Injection Cultivation" This study was initiated on May 2,1997. Two rates of nitrogen were applied using four types of management practices (see study outline below). As of August 28,1997, four treatment applications have been made. Treatments are applied monthly and will run through October. A double rate dormant application will be made in November. Turfgrass evaluations to be made throughout this study include: clipping yields (weekly), color ratings (weekly), quality ratings (weekly), soil moisture content (during periods of turf dry down), and root mass (semi annually). Early results from this study have shown, as expected, that the 1 lb. rate of nitrogen per 1000 ft 2 produced greater clipping yields, color ratings, and quality ratings than the 0.5 lb. rate. Within a week of the initial treatment applications, there were no differences among management practices in turfgrass evaluations. However, since two weeks following initial treatment applications, nitrogen injected with both the #53 and #56 nozzles have consistently had significantly greater clipping yields, color ratings, and quality ratings than surface applications (this was true for both rates of nitrogen). The experimental area has gone through one dry down period since the initiation of the study. Soil moisture values were significantly higher for turf injected with nitrogen than turf

7 receiving surface applications. Water injection cultivation also increased soil moisture values within surface application treatments. STUDY OUTLINE ( Factor A - Management Practices 1. Surface application of N with no water injection cultivation. 2. Surface application of N plus water injection cultivation. 3. Subsurface injection of N with #56 nozzle (2 to 4" injection depth). 4. Subsurface injection of N with #53 nozzle (4 to 6" injection depth). Factor B - N Rate # N per 1000 ft 2 per application # N per 1000 ft 2 per application. ( Treatment Summary 1. N applied on surface with no WIC 0.5 # N per 1000 ft* per application 2. N applied on surface with no WIC 1.0 # N per 1000 ft per application 3. N applied on surface plus WIC 0.5 # N per 1000 ft' per application 4. N applied on surface plus WIC 1.0 # N per 1000 ft' per application 5. N injected with #56 nozzle 0.5 # N per 1000 ft* per application 6. N injected with #56 nozzle 1.0 # N per 1000 ft' per application 7. N injected with #53 nozzle 0.5 # N per 1000 ft' per application 8. N injected with #53 nozzle 1.0 # N per 1000 ft per application ( Plot Plan: North T STUDY #2: "Injection and Surface Application of Labeled Nitrogen" This study was initiated on August 5,1997. The study consists of two treatments; 1 lb. nitrogen per 1000 ft 2 either injected of surface applied. The nitrogen source used in this experiment contains excessive amounts of 15 N (heavy nitrogen atoms) that can be identified using laboratory equipment. Turfgrass cores will be taken at 1, 3,7,14, 21, and 35 days following treatment. These cores will be sectioned into green tissue, thatch, soil at 0 to 4 inches, roots at 0 to 4 inches, soil at 4 to 8 inches, and roots and 4 to 8 inches. Analyzing these core sections for 15 N content will illustrate how application method affects nitrogen fertilizer cycling through soil and turfgrass tissues.

8 Advancements In Biological Control of Poa trivialis N.M. Dykema, A.R. Detweiler, J.M. Vargas Jr., J.F. Powell, A.E. Bacon, D.W. Taube, and H.E. Loose Department of Botany and Plant Pathology Poa trivialis is a common contaminant in seed lots. Once P. trivialis is established in a desirable turfgrass stand, it is very difficult to selectively irradicate. This is a preliminary field study in which P. trivialis has been stressed by treatment with a Xanthomonas bacterium. This organism has been used to cause typical wilt symptoms in P. trivialis that are similar to those seen in creeping bentgrass infected with Xanthomonas campestris (bacterial wilt) Below is a treatment list and plot plan. Treatments 1. Xanthomonas sp. 2. Autoclaved broth 3. Mycoshield 4. Untreated control Rate 10 7 CFU/cm 2 Volume as above 2.5#/1000ft 2 Annlication Interval 3-5 times per week 3-5 times per week 14 days

9 Biological Control of Dollar Spot on Annual Bluegrass Philip J, Dwyer, Jr. and Joseph M. Vargas, Jr. Department of Botany and Plant Pathology Within the past couple of years there have been significant advances in the understanding and use of the biological control organism Tx-1 (Pseudomonas aureofaciens). This has led to its growing use as a tool in managing dollar spot (Sclerotinia homoeocarpa) on turfgrass. The treatments in this study were designed to help further our understanding of Tx-1 and increase its effectiveness as a biological control for dollar spot One part of this study aims to identify if daily applications of Tx-1 in conjunction with a single fungicide application can prolong the effectiveness of the fungicide. To test if this is possible a treatment of Tx-1 applied daily with a single fungicide application will be compared to a treatment of only the fungicide. A treatment of Tx-1 applied daily will also be compared to these treatments. Tx-1 is thought to control dollar spot by producing an antibiotic called PCA which inhibits the growth of the pathogen. It is not certain whether the active Tx-1 or the antibiotic itself is responsible for inhibition of dollar spot To identify if the living Tx-1 or the antibiotic is responsible for inhibition we will compare daily treatments of living Tx-1, boiled Tx-1, and a non- PCA producing mutant of Tx-1. Living Tx-1 will be applied daily at a specific rate, the same application will be made with Tx-1 which have been boiled. By boiling the Tx-1, the organism is killed however the same amount of PCA is applied as is being applied by the livingtx-1 treatment A laboratory generated mutant of Tx-1 was created which does not produce PCA. In the lab this mutant still inhibits the growth of dollar spot similar to the non-mutant Tx-1. The results from the field treatment of this mutant will indicate if there are other antibiotics or factors which may be responsible for inhibition of dollar spot. Treatments Rate Application Interval 1. Tx-1 2. Tx-1 3. Control 4. Daconil Ultrex + Tx-1 5. Daconil Ultrex 6. Banner + Tx-1 7. Banner 8. Tx-1, 8 hr. Growth 9. Boiled Tx Tx-1, Mutant 2x 10 7 CFU/cm 2 2 x 10 7 CFU/cm oz/1000 ft 2 2 x 10 7 CFU/cm oz/1000 ft 2 1 oz/1000 ft 2 2 x 10 7 CFU/cm 2 1 oz/1000 ft 2 1 x 10 7 CFU/cm 2 2 x 10 7 CFU/cm 2 2 x 10 7 CFU/cm 2 5 days/week 1 time/week Applied once 5 days/week Applied once Applied once 5 days/week Applied once 5 days/week 5 days/week 5 days/week

10 Biological Control of Dollar Spot on Creeping Bentgrass With Pseudomonas aureofaciens Tx-1 J.F.Powell, N.M.Dykema, A.Bacon, D.Taube, H.Loose, A.R.Detweiler, and J.M.Vargas, Jr. Department of Botany and Plant Pathology Research at Michigan State University toward management of dollar spot (Sclerotinia homoeocarpa) with a biological control agent has focused on the use of the common soilborne bacterium Pseudomonas aureofaciens. P. aureofaciens is one of the bacteria responsible for natural biological control process of take-all decline, a process in which bacterial populations antagonistic to the take-all pathogen (Gaeumannomyces graminis) increase following onset of the disease. These bacteria reduce disease by colonizing the roots at the sites of infection and producing a variety of antibiotics inhibitory to the pathogen. Over the course of several seasons, take-all is managed by these bacterial populations. P. aureofaciens strain Tx-1 was isolated from a turfgrass sample and exhibited a strong ability to inhibit disease in laboratory assays and has been shown to produce the antibiotic phenazine-l-carboxylic acid (PCA). The intent of this study is to demonstrate the effectiveness of P. aureofaciens Tx-1 for managing dollar spot. Two questions regarding dollar spot management are being addressed in this study. One of which is to get a better understanding of what rate of application is required to achieve dollar spot management. Rates of application being examined range from 10,000,000 to 100,000 bacteria per square centimeter. The bacteria are cultured in the laboratory overnight, quantified, and spray applied five days a week. The other aspect of this study is to gain insight into how dollar spot disease is managed through application of this bacterium. The most likely modes of disease suppression are competition for nutrients and antagonism through production of antibiotics by the bacteria. This should be clarified by comparing treatments consisting of the same rates of live bacteria, bacteria killed by boiling, and bacteria killed by autoclaving. If suppression is due to the bacteria out competing S. homoeocarpa for nutrients, disease suppression should be observed only in the application of live bacteria. If suppression is due to the production of antibiotics by the bacteria, disease suppression should be seen in the live cell and boiled treatments. The boiled treatment will kill the bacteria but does not destroy the PCA maintained within the bacterial cells. The autoclaved bacteria are included as a control for possible fertility effects due to the media the bacteria are grown upon; this treatment subjects the bacteria to high pressures and temperatures which destroy both the bacteria and the PCA. List of Treatments: 1. Live Bacteria 2. Live Bacteria 3. Live Bacteria 4. Boiled Bacteria 5. Autoclaved Bacteria 6. Chlorothalonil 7. Untreated Control 10,000,000/sq. centimeter 1,000,000/sq. centimeter 100,000/sq. centimeter 10,000,000/sq. centimeter 10,000,000/sq. centimeter 3oz./10 days

11 PGR and Rolling Effects On Putting Greens of Three Different Construcion Methods J.A. Hardy and J.N. Rogers, III Department of Crop and Soil Sciences Michigan State University Due to the putting greens focus as the most important location on the golf course requiring quality playing conditions, issues regarding construction and maintenance have long been hot issues for discussion and research. In the summer of 1992 the Michigan Turf Foundation funded the construction of putting green research plots that will help answer questions regarding the effects of different management practices on putting greens with different soil types. The study is being conducted on a 14,000ft 2 putting green constructed in the summer of 1992 and seeded in spring There are three root zone mixes: an 80:20 (sand: peat) mixture built to USGA recommendations, an 80:10:10 (sand: soil: peat) mixture built with subsurface drainage tile; and an unamended sandy clay loam textured (58% sand, 20.5%silt, 21.5% clay) "push-up" style green. The soil types are arranged in a completely randomized block design, replicated three times, and have individual irrigation control. A rolling factor was split across each soil type and rolling was applied three times per week. The PGR's used were foliar-absorbed trinexapac-ethyl (Primo) and root-absorbed fluiprimidol (Cutless). Each was applied at a rate of 0.05oz. a.i./m at five week intervals during the 1996 and 1997 seasons. Data collected included stimpmeter readings, color and quality ratings, thatch accumulation, and rooting data. For both years of the project, rolled plots produced consistently higher stimpmeter readings. Consistent for both years was the reaction time between PGR treatments and green speed. Approximately two weeks after each application the stimpmeter readings were effected by PGR treatments with both PGR's producing higher readings than the check plots. A two-way interaction was also seen both years between two and three weeks after application between rolling and PGR. The effects of the PGR's on stimpmeter readings seemed to wear off three weeks after application. The first application of the PGR's for 1997 were made on May 28. Approximately one week after the application was made a three way inter action was produced for stimpmeter readings on 6/3, 6/4 and 6/8. This was not seen in 1996 or the other applications for At the beginning of the season the native soil plots produced the highest color ratings while the USGA was the worst. Cutless produced lower color ratings than Primo and the check plots throughout both seasons. Thatch weights in native soil plots were significantly lower than in USGA and 80:10:10 plots.

12 Summer Decline on Creeping Bentgrass and Annual Bluegrass J.M. Vargas, Jr., N.M. Dykema, and A.R. Detweiler Botany and Plant Pathology A new syndrome called Summer Bentgrass Decline has been associated with thinning and dying of turf during the warm summer months. It is especially a problem on low cut turf growing in poor environments. This includes greens growing in shaded areas or where there is limited air movement Fungicide combinations applied on preventive basis have been shown to prevent this decline from occurring. These fungicide combinations not only managed disease problems, but also seem to make the turf have a denser appearance. Creeping Bentgrass Study Treatment 1. Protect + Signature 2. Signature + Daconil Ultrex 3. Control 4. Thalonil 90 DF + Signature 5. Signature + CH FLO 6. Signature + EXP A 7. Signature + EXP B 8. EXP A + Cleary 3336 F Rate/1000 ft 2 Interval 8 oz + 4 oz 14 days 4 oz oz 14 days 3.5 oz + 4 oz 14 days 4 oz + 4 fl oz 14 days 4 oz + 4 fl oz 14 days 4 oz + 4 fl oz 14 days 2 fl oz + 2 fl oz 14 days A B C D Annual Bluegrass Study Treatment 1. Signature + EXP A 2. Aliette + Fore WP 3. Signature + Dac. Ultrex 4. Control Rate/1000 ft 2 4 oz + 4 fl oz 4 oz + 8 fl oz 4 oz oz Interval 14 days 14 days 14 days A B C

13 Golf Soles and Golf Greens: Then & Now Thomas A. Nikolai Department of Crop & Soil Sciences In 1914 Walter Hagen won the U.S. Open wearing hobnails on the soles of his shoes. His victory is credited with fueling the trend toward golf spikes. By 1920 golf shoes with spike soles were considered standard attire. In the latter half of the 40's golf course superintendents complained about lug soles leaving indentations on their greens. This led to the first golf sole research conducted in A decade later golf course superintendents protested about ripple soles leaving indentations on the green surface. Thus, in 1959 research was conducted comparing metal spikes to ripple soles. Twenty years later multi-stud and suction cleats earned the ire of golf course superintendents and golf sole research was conducted for the third time in the century. All three studies concluded that metal golf spikes caused the most damage in the long run. However, lug, ripple, suction cleats, and multi-stud soles all disappeared from the golfer attire. In some cases the disappearance was fueled by golf clubs banning the soles. So why has all research concluded that metal spikes cause the most damage yet alternative sole designs (prior to the 90's) have disappeared "? To assist us in an answer we look at the results of a 1959 survey conducted by the USGA. Golf course superintendents were asked,"which shoe sole type do you consider most damaging to putting green turf!" The Results: * Ripple = 135 * Lug = 50 * Spike = 46 * All = 5 The results lead us to conclude that indentations made by non-metal soles were considered more detrimental to daily putting quality than metal spikes. So what if research concluded that metal spikes were more detrimental in the long run. The golf course superintendents job has relied upon the payability of the course on a day to day basis. Long term problems are repaired with fertility, rolling, aerification or some other cultural practice. So what changes have led to metal spikes being banned at golf clubs in the 90's"? To answer this question consider the changes of cultural practices on putting greens. Mowing heights have decreased significantly over the decades. By the early 1980's the practice of sand topdressing greens became vital to maintain surface smoothness as cutting heights decreased. In turn the tri-

14 weekly sand topdressing programs all but eliminated thatch as a problem on greens. We hypothesize that greens maintained at.25 inch cutting heights with.75 inches of thatch would show more traffic damage by indentations than the uplifting of turf. In contrast the firmer surfaces of the 90's golf green favor more visual traffic by the uplifting of grass plants than the indentations of the non-metal soles or spikes. Today, many universities are conducting research with the newer spike alternatives. At Michigan State University we think its time to ask the golf course superintendent what he thinks. For Field Day 20 golf greens maintained at a 5/32" cutting height have been trafficked with different golf shoe bottoms. The treatments include 16 different spikes on Dry Joy golf shoes. The sixteen different spikes are listed below. Aerospike Greenkeepers Greenpike Gripper(ceramic) Gripper(poly) Flatspikes SmartSpikes Softpikes Softpikes EP Softpikes EP Tred Lite MT Tred Lite SP Turf Mate Turf Mate + 8mm metal spikes 6mm metal spikes There are also three different golf sole bottoms. Two are from Etonic and one from Nike. The Nike have solid rubber outsoles with a high traction design and the Nike Waffle Spike. One pair of Etonic have replaceable DSS-1 Spikes incorporated into their molded outsole. The final pair of Etonic has no spikes and is a formed outsole for high traction. The final green received no traffic. All greens have been sand topdressed regularly for the past two months. Participants will be asked to rate each of the twenty greens and pieces of plywood trafficked with each of the golf soles.