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Crop Science 42:2018-2024 (2002)
© 2002 Crop Science Society of America

TURFGRASS SCIENCE

Turfgrass Evaluation of Native Grasses for the Northern Great Plains Region

A. S. Mintenko*,a, S. R. Smithb and D. J. Cattanic

a Soils and Crops Branch, Manitoba Agriculture and Food, Carman, MB, Canada, Box 1149, R0G 0J0
b Virginia Tech, Dep. of Crop and Soil Environmental Sci., Blacksburg, VA 24061
c Pesticide Management Regulatory Agency, Ottawa, ON, Canada, K1A 0K9

* Corresponding author (amintenko{at}gov.mb.ca)


   ABSTRACT
TOP
 ABSTRACT
INTRODUCTION
 MATERIALS AND METHODS
 RESULTS AND DISCUSSION
 CONCLUSION
 REFERENCES
 
A range of native grass species evolved under the environmental extremes of a continental climate in the northern Great Plains, but most have not been evaluated for their suitability as turf. The objective of this research was to evaluate the turfgrass potential of a range of native grasses under three mowing heights. Twelve species (a total of 28 entries) were evaluated under three mowing heights (62, 38, and 18 mm), for turf quality, color, and density at two locations in Manitoba, Canada. The species evaluated included alpine bluegrass (Poa alpina L.), alkali grass [Puccinellia nuttalliana (Schult.) Hitchc.], alpine fescue [Festuca ovina L. var. brachyphylla (Schult. & Schult. f.) Piper, syn. F. brachyphylla Schult. & Schult. f.], blue grama [Bouteloua gracilis (Kunth) Lag. ex Griffiths], buffalograss {Buchloe dactyloides (Nutt.) Engelm. [= Bouteloua dactyloides (Nutt.) Columbus]} Canada bluegrass (Poa compressa L.), fescue spp., fowl bluegrass (Poa palustris L.), Idaho bentgrass (Agrostis idahoensis Nash), marsh muhly [Muhlenbergia racemosa (Michx.) Britton et al.], prairie junegrass [Koeleria macrantha (Ledeb.) Schult.], rough hairgrass {Agrostis scabra Willd. [= A. hyemalis var. scabra (Willd.) H. L. Blomq.]}, side-oats grama [Bouteloua curtipendula (Michx.) Torr.], and tufted hairgrass [Deschampsia cespitosa (L.) P. Beauv.]. Entries showed similar results across all mowing heights. ‘Bad River’ blue grama, Minnesota ecotype blue grama, and ‘Barkoel’ prairie junegrass entries showed high quality ratings across all years and locations. Blue grama, a warm-season grass, was drought tolerant and maintained consistent green color throughout the growing season. Although a number of the species showed promise, most entries will require a breeding and selection program before release as low-maintenance turfgrasses.


   INTRODUCTION
TOP
 ABSTRACT
 INTRODUCTION
MATERIALS AND METHODS
 RESULTS AND DISCUSSION
 CONCLUSION
 REFERENCES
 
PUBLIC PRESSURE is increasing for the turfgrass industry to reduce maintenance inputs (Brede, 2000). Traditional species like Kentucky bluegrass (Poa pratensis L.), perennial ryegrass (Lolium perenne L.), and tall fescue (Festuca arundinacea Schreb.) require significant amounts of water and fertilizer for a lush, green, dense stand (Bormann and Balmori, 1993). Although there have been numerous attempts to identify low maintenance turfgrass species, most have focused on traditional introduced species (i.e., species not native to North America) (Aronson et al., 1987; Fry and Butler, 1989; Dernoeden et al., 1994; McKernan and Ross, 1997). During the last 15 yr, turfgrass breeders have been trying to develop cultivars of these traditional turfgrass species that require fewer inputs. During the last 5 yr, a number of new low-maintenance cultivars of perennial ryegrass, tall fescue, and Kentucky bluegrass have been released that will maintain turfgrass quality with less N and watering (National Turfgrass Evaluation Program, 1998a, b,c).

Native grasses of the northern Great Plains may be good candidates for low maintenance or xeriscape turf (Holzworth, 1990). These species have evolved under the environmental extremes of a continental climate, but most have not been evaluated for their suitability as managed turf. A number of publications mention native grasses for turfgrass use, but most refer to nonmown or infrequent mowing situations as opposed to managed turfgrass (Jacobson, 1996; Davidson and Gobin, 1998). Recent low-maintenance turfgrass trials have utilized commercially available introduced species such as the Festuca spp. (Dernoeden et al., 1994, 1998; McKernan and Ross, 1997). When native grasses have been evaluated, only those species with readily available seed supplies were selected for study (e.g., Canada bluegrass) (Diesburg et al., 1997; McKernan and Ross, 1997). Furthermore, few native grasses have been examined for turf use under intensive mowing heights (Mintenko and Smith, 1998, 1999).

The native grass that has been most extensively investigated for managed turf stands is buffalograss (McCarly and Colvin, 1992; Browning et al., 1994; National Turfgrass Evaluation Program, 1995; Qian et al., 1997). This grass, native to central and western USA, has been growing in popularity as a turf during the last 10 to 20 yr. Buffalograss is a true low maintenance turfgrass with its low growth habit, drought tolerance, and natural competitiveness (Feldhake et al., 1984; Lambert and Colvin, 1992; Bowman et al., 1998; Wu et al., 1998). Although early buffalograss cultivars required establishment with vegetative plugs or sod, there are now a number of seeded cultivars (National Turfgrass Evaluation Program, 1995).

The objective of this research was to evaluate the turfgrass potential of a range of cool- and warm-season native grasses under three mowing heights.


   MATERIALS AND METHODS
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
RESULTS AND DISCUSSION
 CONCLUSION
 REFERENCES
 
This experiment was established in 1996 at the University of Manitoba Plant Science research stations in Winnipeg (21 June) and Carman (3 July), MB, Canada. The Winnipeg trial was planted on a Cumulic Regosol clay-loam soil with a pH of 7.6 (Dep. of Soil Science, Univ. of Manitoba). The Carman trial was planted on an Orthic Black Chernozem sandy-loam soil with a pH of 7.2 (Dep. Soil Science, University of Manitoba). Both locations can be characterized by an extreme range in environmental conditions typical of the Great Plains region of North America (USDA Zone 3). Winter lows of -35 to -40°C are not uncommon and summer highs of 40°C have been recorded. Average annual precipitation is 550 mm at Winnipeg and 500 mm at Carman, with approximately one-third falling as snow. Growing season precipitation from 1997 to 2000 and the long-term average are shown in Table 1 .


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  		Table 1. Summary of monthly precipitation at Winnipeg and Carman, MB, Canada locations from 1997 to 2000 and average monthly precipitation from 1961 to 1990.

 
The first year (1996) was considered an establishment year, with mowing treatments and data collection starting in 1997. The species evaluated included alpine bluegrass, alkali grass, alpine fescue, blue grama, and buffalograss, Canada bluegrass, fowl bluegrass, Idaho bentgrass , marsh muhly, prairie junegrass, rough hairgrass, side-oats grama, and tufted hairgrass (Table 2) . Seed was broadcast at 10 g m-2 (adjusted for percentage live seed) with the exception of ‘Golfstar’ Idaho bentgrass at 5 g m-2 due to its smaller seed size. Following seeding, both trials were covered with Famcomat (fiberglass mat cover manufactured by AAF International, Lousiville, KY) to facilitate germination and to reduce the chance of seed movement between plots. The cover was removed 10 d after seeding. Both trials were irrigated as required to ensure a moist seedbed during germination and emergence. Irrigation was applied on a weekly to biweekly basis the remainder of the summer to alleviate moisture stress and encourage root growth. Irrigation in 1997 was limited: 25 mm of additional water was applied to the plots if rainfall during the previous 3-wk period was <25 mm. Irrigation was applied only two times in 1997. However, to more closely simulate low-maintenance conditions, no irrigation was applied in 1998, 1999, and 2000.


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  		Table 2. Native grasses seeded in the turfgrass evaluation experiments in Winnipeg and Carman, MB, Canada, in 1996.

 
In order to evaluate a wide range of species and geographic origins, 12 native grass species were sourced from across western Canada and the western USA primarily through contacts in the seed trade and conservation organizations (Table 2). Species such as buffalograss, where adapted northern material is limited, were obtained from the south-central USA. Several species were represented more than once, resulting in a total of 28 entries. The experimental design was a randomized complete block in a split-block arrangement with four replications. Native grass entries were the main plots, 1 by 3 m, with mowing treatments splitting each entry into three 1-m2 subplots.

Native grass entries were subjected to different heights of mowing: 18, 38, and 62 mm. These mowing treatments were designed to approximate the heights of cut synonymous with a low-maintenance fairway, a home lawn, and a golf course rough, respectively. The Kansas blue grama was only planted in Winnipeg due to insufficient seed supply. Mowing frequency for each treatment was weekly (with clippings removed) with a rotary mower (John Deere 14 PZ 21-inch walk behind rotary mower). The 18-mm mowing height was achieved with the rotary mower at 38 mm and a second pass with a wheel-driven reel type mower at 18 mm (Scotts Silent Hand Push-Reel Mower). Each year, mowing treatments were initiated in the middle of May and ceased at the end of September.

Soil fertility was monitored monthly throughout the growing season, with fertilizer application occurring in June, July, and August of 1997, 1998, 1999, and 2000. In the establishment year of 1996, one application of a water-soluble fertilizer (20-20-20, NPK, Nu-Gro, Calgary, AB, Canada) occurred in early August, with total nutrients of 50 kg N, 50 kg P, and 50 kg K ha-2 yr-1 applied. In 1997, a water soluble fertilizer (17-17-17, Crop King, Border Chemical, Winnipeg, MB, Canada) was applied at 25 kg N, 25 kg P, 25 kg K ha-2 yr-1, while in 1998, 1999, and 2000, a slow release fertilizer (32-4-8, Nu-Gro) was applied for a total of {approx}25 kg N, 3 kg P, 6 kg K ha-2 yr-1. Fertilizer was applied to compensate for nutrient loss as a result of grass clipping removal and was only applied at half the nutrient rate recommended by soil tests to maintain established turfgrass. Weed control in 1996 consisted of hand weeding only. From 1997 to 2000, a herbicide mixture of 62% 2,4-D [(2,4-diclorophenoxy) acetic acid], 32% mecoprop [2-(4-chloro-2-methyl phenoxy) propionic acid], and 6% diacamba (3,6-dichloro-0-amisic acid) at 2.5% concentration was applied in early July.

Monthly visual measurements of turf quality, color, and percentage ground cover were recorded. Turf quality ratings from 1 to 9 were: 1 = poor, 5 = adequate, and 9 = ideal turfgrass. Turf quality ratings involved a combination of color, density, disease, uniformity, winter injury, and plant vigor factors (National Turfgrass Evaluation Program, 1998d). Turf color ratings from 1 to 9 were: 1 = brown or yellow, 5 = light green, 7 = blue-green, and 9 = dark green. In this study, native grass entries with potential were determined as those that showed moderate to high turfgrass quality (ratings >= 5) across all years, at all mowing heights, and at both locations. Percentage visual ground cover range was measured with 0% for plots with no vegetative cover and 100% for plots where vegetative cover was complete with no visible soil (weeds excluded). Regrowth after mowing was measured every 2 wk, and spring green-up and fall dormancy ratings were measured weekly. Ratings of percentage winterkill and turfgrass texture were also measured on a one-time basis.

Data was analyzed with a split-block design across locations and years, where locations were fixed effects and years random effects (McIntosh, 1983) (Table 3) . Cool- and warm-season grass entries were analyzed as two distinct groups, reflecting their biological differences. Consistent significant interactions between years, locations, months, and mowing heights with entry were found; therefore, pooling of data within each source of variation was not possible (Little and Hills, 1978) (Table 3). A rank correlation analysis was conducted across all years, locations, and mowing heights within months in order to provide pooling of data and provide a rank of each entry. Rank correlation results showed similar ranking occurred between years, locations, and mowing heights within months.


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  		Table 3. Split-block analysis of variance for the month of July of cool-season entries turfgrass quality for the turfgrass evaluation of native grasses across all years (4), locations (2), and mowing heights (3).

 

   RESULTS AND DISCUSSION
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
 RESULTS AND DISCUSSION
CONCLUSION
 REFERENCES
 
Statistical analysis showed consistent interactions between years, locations, mowing heights, and entries, which was expected given the number of species involved and the different environmental conditions for each year and location (Table 3). Although pooling of data was not possible, correlations allowed ranking of entries across mowing heights and locations. Quality ratings for each entry were relatively consistent within months across all mowing heights and locations, as reflected by the rank correlations averaging in the high 95% range. Late spring green-up and early fall dormancy reduced quality of warm-season grasses across all mowing heights in May and September of each year (data not shown).

Bad River blue grama, Minnesota ecotype blue grama, and Barkoel prairie junegrass had consistently high turfgrass quality ratings across all years (1997–2000) and mowing heights (62, 38, and 18 mm) at both locations (Table 4) . Entries with high turfgrass quality ratings maintained adequate percentages of ground cover (>70%), had limited disease or pest problems, high adaptability to mowing stress, consistent green summer color, and a fine leaf texture (Tables 4, 5) .


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  		Table 4. Comparing across time visual turfgrass quality ratings from June 1997 to August 2000 across all mowing heights (62 cm, 38 cm, 18 cm) and locations (Winnipeg and Carman, MB, Canada), and turfgrass texture ratings for the native grass turfgrass evaluation.

 

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  		Table 5. Variations in percentage ground cover in June 1997 and August 2000 and visual turfgrass color ratings from May to September 1999 for the native grass turfgrass evaluation at the 38-mm mowing height in Carman, MB, Canada.

 
Although Barkoel prairie junegrass originated from plants collected in northern Europe, it may indicate the potential of the North American junegrasses for turfgrass use. It showed excellent color and density with moderate drought tolerance, but spring green-up was not as early as the North American junegrasses and the leaves were subject to shredding after mowing (data not shown). Disease problems were low for all junegrass entries, except for a mild rust (unidentified) infestation during hot, humid periods in 1997 and 1998.

The high quality ratings of Barkoel prairie junegrass was not surprising, as it is the product of a breeding and selection program and has been released for use as a turfgrass cultivar. However, Bad River and Minnesota ecotype blue grama entries were collections from native stands with no subsequent breeding. The high quality ratings indicate the potential of this species as a low-maintenance turfgrass. Blue grama entries are essentially ecotypes and have only been selected for seed yield or plant vigor. These entries showed excellent drought tolerance, good winter hardiness, texture, and color, and were adapted to mowing stress (Tables 4 and 5). Limitations, however, included late spring green-up and early fall dormancy typical of warm-season grasses and plant densities below ideal turfgrass density levels (>80%). Most of the warm-season grasses had complete green-up by mid-May to early June and fall dormancy beginning in mid-September with complete dormancy by early October across all years. Most cool-season grass entries showed complete green-up by early May and fall dormancy onset in mid to late October.

Other entries showed moderate turfgrass quality ratings (ratings equal to 4 or 5). These entries were: Alberta ecotype fowl bluegrass, Alberta ecotype rough hairgrass, ‘Nortran’ tufted hairgrass, Alberta ecotype tufted hairgrass, Iran ecotype prairie junegrass, and Golfstar Idaho bentgrass (Tables 4, 5). These entries showed good texture and density, but had reduced quality as a result of disease pressures or drought intolerance (Tables 4, 5). However, the Alberta ecotype fowl bluegrass maintained a very high turf cover, which is beneficial for many uses (Table 5). In the cooler and higher moisture conditions of spring and fall, the cool-season entries had moderate turfgrass quality, but quality decreased throughout July and August as temperatures increased and precipitation decreased. Both tufted hairgrass entries in this grouping experienced severe rust (unidentified) infestations beginning in July in all years, leading to reduced quality and color ratings (Table 4). Tufted hairgrass entries showed excellent density, texture, and adaptation to mowing stress, and would have received much higher quality ratings in the absence of rust. Golfstar Idaho bentgrass had excellent color, density, and responded well to low mowing heights initially, but showed poor drought tolerance. Turfgrass quality and percentage cover of this entry decreased from 1997 to 2000 as a result of snow mold (pink and grey) damage across three consecutive winters. This was most apparent at the Winnipeg location, where snow mold inoculum likely spread from adjacent turfgrass research areas. There was less snow mold at the Carman location, as this area had been planted to agricultural crops for many years.

Sharp's Imp. II buffalograss and the Kansas ecotype blue grama had acceptable quality ratings in 1997, however, subsequent winterkill reduced quality during of the trial (Table 4) (data not shown for Kansas blue grama). This loss of turf density was expected as most warm-season native grasses are less winter hardy when planted more than 450 km north of their origin (Smith and Smith, 1997). The Kansas blue grama entry never recovered from winterkill damage. Buffalograss, as a result of its aggressive spreading nature, had recolonized a high percentage of winterkilled spots within plots during the summer. Buffalograss showed excellent drought tolerance, color, texture and adapted very well to mowing stress (Tables 4, 5). Similar spring and fall dormancy ratings were observed for this entry and for Kansas blue grama. A more northerly sourced buffalograss, ‘Bismarck’, has been recommended as a low-maintenance turfgrass for the northern Great Plains region. Bismarck buffalograss is a male vegetative ecotype from North Dakota that has shown consistent high quality and percentage cover in turfgrass trials with no winterkill damage (Mintenko, 2000).

The last group of entries were those that received low turfgrass quality ratings (ratings <4) and texture rankings (Table 4). Low quality ratings generally resulted from a combination of the following: low plot density, brown turfgrass color, disease problems, poor drought tolerance, or poor recovery from mowing stress. The side-oats grama entries had excellent drought tolerance and color, typical of warm-season grasses, but its coarse texture and low percentage ground cover scores for these entries resulted in low quality ratings (Tables 4 and 5).

The Carman location generally had higher quality ratings for all entries than the Winnipeg location; however, rankings remained similar. Soil conditions at Carman were more representative of short and mixed grass prairie soils where most of these grasses originated. The heavy clay soils of the Winnipeg location were more representative of river bottom or flood plain conditions originally dominated by tall grass species.

Color varied widely among all the entries (Table 5). The higher-quality entries had high color ratings (7–9) indicating a blue-green (7) to dark green color (9). Entries that did not tolerate mowing stress showed lower color ratings as a result of very slow regrowth of grass blades or the loss of a majority of leaf material under the intensive mowing heights (e.g., Canada bluegrass entries). Another indication that many entries showed poor tolerance to mowing stress was decreased ground cover across years (Table 5). Alkali grass provides a good example, with relatively high ground cover scores at all mowing heights in June 1997 and very low cover by August 2000. Alkaligrass cultivars have been selected for improved turf quality and may better serve this market (Brede, 2000). Entries that sustained winterkill also had lower ground cover scores in 2000 compared with 1997. Winterkill is likely to occur when plant reserves are decreased by disease and mowing stress. Either condition likely reduced the total amount of root and crown reserves necessary to prevent winter damage (DiPaola and Beard, 1992).

Measurements of regrowth after mowing provided an indication of the influence of precipitation and soil moisture on growth rate in cool- and warm-season grasses. All grasses showed decreasing regrowth with decreasing precipitation amounts, especially at Carman in 1998. Regrowth trends were similar for all three mowing heights, and only the 62-mm mowing height is shown (Fig. 1) . Linear trendlines indicated a relationship between decreased precipitation and regrowth in cool-season grasses (cool-season linear slope: y = -3.5563x + 81.581, with R2 = 0.8111). Decreasing daylength and the onset of fall dormancy were important factors that caused reduced regrowth of the warm-season grasses (warm-sesason linear slope: y = -2.0536x + 87.839, with R2 = 0.0793). The top entries showed little connection between precipitation and regrowth, while lower quality entries were more affected by decreasing precipitation, with slower recovery from mowing stress. The many factors that affect the regrowth of each native grass entry deserve further study.



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  		Fig. 1. Regrowth totals 1 wk after mowing at the 62-mm mowing height and precipitation amounts during that period for the native grass evaluation study in 1998 at Carman, MB, Canada.

 
Disease and Pest Problems Limited
Most entries had no or limited disease or insect pest problems. This may be expected with native grasses that have evolved under the stresses of the northern Great Plains region. Snow mold, a common disease problem in Manitoba, was generally absent with the exception of Golfstar Idaho bentgrass and rough hairgrass. A major rust infection occurred on all tufted hairgrass entries, with minor rust infestations on the junegrasses. Rust reduced the turfgrass quality of the tufted hairgrass entries from excellent under cool spring temperatures, to poor during warm, humid summer conditions.


   CONCLUSION
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
 RESULTS AND DISCUSSION
 CONCLUSION
REFERENCES
 
The results of this experiment indicted that several native grass species are suitable for low-maintenance turfgrass use. Blue grama and most of the moderate quality entries in this experiment were collections from remnant native stands with very little or no selection for turfgrass use. The ratings may have varied if a slightly higher irrigation level was used or different fertilization schedules used. The longer dormancy period of the warm-season grasses may be less acceptable to many users. These entries are possible candidates for future turfgrass breeding and selection programs. The high turfgrass quality ratings of many of the blue grama entries suggest that native harvested seed may be suitable for some turfgrass plantings (i.e., public parks and golf course roughs). As a result of this experiment, the University of Manitoba has initiated a turfgrass breeding and selection program for blue grama. Before widespread public use of native grasses becomes a reality, more research needs to be conducted with respect to their use as turfgrasses.


   ACKNOWLEDGMENTS
 
The authors wish to thank Mr. Matt Fruehm, Mr. Mike Wartman, and Dr. Anh Phan for their technical assistance. Funding for this project was provided in part by the Canadian Turfgrass Research Foundation, Agri-Food Research Development Initiative, and the Manitoba Seed Producers Consortium.

Received for publication September 2, 2001.


   REFERENCES
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
 RESULTS AND DISCUSSION
 CONCLUSION
 REFERENCES
 




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