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Production Papers

Forage Chicory and Plantain

Nutritive Value of Herbage at Variable Grazing Frequencies and Intensities

^a Dep. of Agric. and Nat. Res., Delaware State Univ., 1200 N. Dupont Hwy, Dover, DE 19901
^b USDA-ARS Pasture Syst. and Watershed Manage. Res. Unit, Bldg. 3702 Curtin Rd., University Park, PA 16802-3702
^c Crop and Soil Sci. Dep., Pennsylvania State Univ., University Park, PA 16802

^* Corresponding author (mlabreveux{at}desu.edu)

Received for publication January 9, 2005.

	ABSTRACT

TOP NOTES ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS AND DISCUSSION CONCLUSIONS REFERENCES

 
Cultivars of forage chicory (Cichorium intybus L.) and plantain (Plantago lanceolata L.) grown in the northeastern USA have acceptable seasonal productivity; however, their reproductive habit could limit herbage nutritive value. The nutritive value of chicory and plantain cultivars was compared and examined under the effect of variable frequency and intensity of grazing. The cultivars were compared with ‘Pennlate’ orchardgrass (Dactylis glomerata L.), a productive grass during the summer, in two grazing experiments in 3 yr. Pre-grazing herbage samples were analyzed and compared for crude protein (CP), neutral detergent fiber (NDF), and in vitro true digestibility of dry matter (IVTD). In both experiments, the average CP of entries was 180 to 200 g kg^–1, similar to orchardgrass. The NDF of forbs, which ranged from 300 to 400 g kg^–1, was 200 g kg^–1 lower than orchardgrass. The IVTD of chicory cultivars averaged 850 to 950 g kg^–1. In Exp. 1, ‘Forage Feast’ and ‘Puna’ chicory had the greatest IVTD (5% greater than orchardgrass: average 911 vs. 867 g kg^–1, respectively; P < 0.05). Lancelot plantain had the lowest IVTD in both experiments. Grazing management (frequency of grazing) affected nutritive value in Exp. 1 but not in Exp. 2. Although herbage composition in Exp. 2 varied, continuous reproductive development did not affect nutritive value. Managing Puna chicory and Lancelot plantain using a canopy-height based grazing system to maximize yield and persistence does not compromise nutritive value. Puna chicory could be a good complement to Pennlate orchardgrass in grass-based feeding systems.

	INTRODUCTION

TOP NOTES ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS AND DISCUSSION CONCLUSIONS REFERENCES

 
MAINTAINING acceptable forage productivity and quality during the grazing season can be difficult, particularly in areas where cool-season pasture species predominate. In these circumstances, the use of alternative forage species has been considered to increase forage production during the summer. Crops such as chicory and English plantain have been tested for this purpose (Jung et al., 1996; Holden et al., 2000; Foster et al., 2002; Sanderson et al., 2003a, 2003b; Belesky et al., 2000, 2001, and 2004). Research suggests that forage chicory can complement and even improve seasonal dry matter (DM) productivity of pastures in the northeastern USA (Sanderson et al., 2003a; Labreveux et al., 2004), where, aside from alfalfa, species such as orchardgrass and reed canarygrass predominate due to their summer yields. Cultivars of forage plantain have the potential of improving overall pasture digestibility, average animal performance, and the micronutrient balance of pastures (Belesky et al., 2001; Sanderson et al., 2003b). Nevertheless, these species have shown low tolerance to simulated winter temperatures (Skinner and Gustine, 2002), which may hinder their use as perennial forbs.

The chicory cultivar Grasslands Puna released in 1985 frequently has been used in the USA and is reported to have good summer productivity (Jung et al., 1996; Volesky, 1996). This cultivar can have similar or higher digestibility as perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens L.) mixtures (Hoskin et al., 1999) and birdsfoot trefoil (Lotus corniculatus L.) (Fraser and Rowarth, 1996; Min et al., 1997). Additionally, its faster rumen degradation and rates of passage improved voluntary feed intake and growth rate of deer (Cervus elaphus) grazing chicory (Kusmartono et al., 1997). Forage chicory has also been recommended to improve summer and fall energy levels and to increase the growth potential of red deer calves (Stevens and Corson, 2003). Increases in milk solids during the summer as a consequence of supplementing dairy cows with Grasslands Puna chicory have also been reported (Waugh et al., 1998). Other chicory cultivars, such as Forage Feast and INIA LE Lacerta, have become available; however, there is little information on their nutritive value or performance in the USA (Belesky et al., 1999; Foster et al., 2002; Sanderson et al., 2003a, 2003b).

Plantago species are widely represented in grasslands around the world (Kuiper and Bos, 1992; Scehovic and Jeangros, 1994; Tracy and Sanderson, 2004). Recently, these two cultivars have been developed for use as forage: Grasslands Lancelot (New Zealand Pastoral Agriculture Research Institute Ltd., 1996) and Ceres Tonic (Pyne Gould Guinness Ltd., 1996). These cultivars were selected for their upright growth habit and larger leaves than naturally occurring types. Leaves of plantain cultivars are reported as highly palatable to animals and to have a similar digestibility to perennial ryegrass and birdsfoot trefoil pastures (Fraser and Rowarth, 1996; Stewart, 1996; Rumball et al., 1997).

Reproductive structures of chicory and plantain form throughout the entire growing season. This characteristic could potentially reduce the nutritive value of the herbage and may constitute a disadvantage when used under grazing conditions. As opposed to haying and mowing situations where pasture species are subjected to uniform cutting heights and regular cutting intervals, grazing animals generate uniformly grazed areas and rejected patches that could greatly affect the overall nutritive value of the pasture (Griffiths et al., 2003). Adjustments to the grazing management strategy can aid in controlling the canopy structure of a pasture and its potential nutritive value (Garcia et al., 2003; Burns et al., 2002). For chicory, Li et al. (1997) in New Zealand and Volesky (1996) in Oklahoma reported that grazing time intervals, or rest periods, of 4 and 5 wk were more productive than those 1 or 2 wk long. Additionally, we suggested that yield and persistence of chicory and plantain cultivars could be positively affected by using variable, as opposed to a fixed, time intervals to grazing (Labreveux et al., 2004). Variable time intervals can be achieved by using canopy height as the determinant of the length of the rest period. The strategy allows for variable intervals between grazing events that are determined as a function of seasonal changes in the regrowth rate of the pasture (Burns et al., 2002). In this article, we compare the nutritive value of chicory and plantain cultivars and examine if the variable time interval between grazing events would negatively affect the nutritive value of the cultivars.

	MATERIALS AND METHODS

TOP NOTES ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS AND DISCUSSION CONCLUSIONS REFERENCES

 
Two grazing experiments were conducted at the Pennsylvania State University Haller Farm Beef Research Center near State College, PA. The soil at the experimental site was a Hagerstown silt loam (fine, mixed, mesic Typic Hapludalfs).

Experiment 1
Chicory cultivars Forage Feast, Grasslands Puna, and INIA LE Lacerta; plantain cultivars Grasslands Lancelot and Ceres Tonic; and Pennlate orchardgrass were seeded in pure stands in May 1997. Chicory was seeded at 4.5 kg ha^–1. Plantain and orchardgrass were seeded at 11 kg ha^–1. Soil tests to 150 mm depth in March 1998 indicated a pH of 6.3 and 93, 489, and 256 kg ha^–1 of P, K, and Mg, respectively. No fertilizer was added at planting. Urea was applied on 10 April and 15 June 1998 at 50 kg N ha^–1 N. A total of 60 and 120 kg ha^–1 of P and K, respectively, was applied in April. Mowing controlled weeds during the year of establishment.

A randomized complete block (four replicates) design with a split-plot arrangement of treatments was used with cultivars randomly assigned to subplots within the grazing treatment main plots. Subplot size (cultivars within grazing treatment) was 12 by 14 m, resulting in a main plot size of 72 by 14 m and a block size of 72 by 56 m. The grazing treatments consisted of all combinations of frequency (3- and 5-wk rest period) and intensity (50 and 150 mm post-grazing stubble height) of grazing. All cultivars (subplots) within a grazing treatment (main plot) and block were grazed at the same time. The number of animals per paddock at each grazing event (12 to 14 cow-calf pairs) was adjusted to minimize the grazing period (no longer than 36 h) and to avoid pasture damage. Grazing began on 5 May 1998 and ended on 9 September 1998. Paddocks were grazed between five and eight times during the year. Herbage was collected from all subplots before grazing from four 0.1 m² quadrats cut to ground level with electric shears. One of four pre-grazing herbage samples was separated into seeded and nonseeded species. All material was oven dried at 55°C for 48 h and weighed to estimate DM yields (reported in Labreveux et al., 2004). Nutritive value analysis was performed on a selected set of samples (date dependent).

Nutritive value data were statistically analyzed using the MIXED procedure (SAS Institute, 1998). Due to the nature of the study (unequal cell size and/or potential missing data), data within each harvest date were compared using planned contrasts (Steel et al., 1997). Planned cultivar comparisons were Forage Feast chicory vs. Pennlate orchardgrass (Penn), Lacerta chicory vs. Penn, Puna chicory vs. Penn, Tonic plantain vs. Penn, and Lancelot plantain vs. Penn. Grazing treatment by cultivar means were compared for the effect of grazing treatment within each cultivar. Planned grazing treatment comparisons were frequently (3-wk interval) vs. infrequently (5-wk interval), severely (50 mm post-grazing stubble height) vs. lightly (150 mm post-grazing stubble height), and the interaction of grazing frequency and intensity. Comparisons were considered significantly different at P < 0.05.

Experiment 2
Pure stands of Grasslands Puna chicory, Grasslands Lancelot plantain, and Pennlate orchardgrass were seeded on August 1999 in a different field with similar soil type at the Haller Beef Research Farm. Soil tests before planting indicated a pH of 6.5 and P, K, and Mg levels of 89, 325, and 205 kg ha^–1, respectively. Before seeding, weeds were controlled with glyphosate [N-(phosphono-methyl) glycine]. Seeding rates were the same as those used in Exp. 1. Mowing controlled weeds during establishment. Grazing experiments were conducted in 2000 and 2001.

In 2000 and 2001, N fertilizer in the form of urea was applied in May and August at a rate of 40 kg N ha^–1. The experimental site was approximately 2.2 ha, and each experimental unit was 0.09 ha. A split-block design (four blocks) was used. Two grazing-intensity treatments were developed based on the yield and persistence results from Exp. 1 (Labreveux et al., 2004) that were defined by the post-grazing stubble height left during spring and summer. The "severe" treatment plots were grazed to an average canopy height of 50 mm, whereas the "severe–moderate" plots were grazed to a 50-mm post-grazing stubble height in spring and 100 mm in summer. The grazing cycle was defined by the time required to reach a canopy height of 250 mm for orchardgrass and chicory and 200 mm for plantain. Pre-grazing canopy height was monitored twice a week, and time to grazing was determined according to these results. Height monitoring was done with a meter stick, and height was defined as that of the first vegetative leaf (standing and not trampled in the case of post-grazing measurements) touching the measuring device, with 25 readings per plot. Residual height was measured once or twice during the occupation period (length of time when animal occupy one paddock). Species were grazed five times in 2000 and four times in 2001, with the exception of orchardgrass, which was grazed five times in both years. Nutritive value analysis was performed on a selected set of samples (date dependent).

Pre-grazing herbage samples were taken from two 2-m sections of a drill row and separated into leaves, flower stalks, dead leaves, stubble, and weeds. All samples were oven dried at 55°C for 48 h and weighed.

The MIXED procedure with repeated measures over years was used to perform the statistical analyses (SAS Institute, 1998). A compound symmetry covariance structure was selected as the one that best fit the data. Replicates (blocks) and interactions with replicates were considered to be random effects, and years were considered as fixed effects. Guidelines for the analysis of data were based on Steel et al. (1997) and Littel et al. (1996, 1998). Planned contrasts were used to compare means (Steel et al., 1997). Cultivar comparisons were Puna chicory vs. Penn and Lancelot plantain vs. Penn. Grazing effect was tested on summer data using the contrast "severe" vs. "severe–moderate". Planned contrast for year comparison was 2000 vs. 2001. Comparisons were considered significantly different at P < 0.05.

Nutritive Value Analysis
Herbage was ground to pass a 2-mm screen in a shear mill and then a 1-mm screen in an impact mill. Although ANKOM technology manufacturers recommend a 2-mm herbage grinding for use with some of their systems, the grinding technique was kept consistent with research conducted before their findings (Sanderson et al., 2003). Ground samples were analyzed for crude protein (CP) (N x 6.25), neutral detergent fiber (NDF), and in vitro true DM digestibility (IVTD) by near-infrared spectroscopy with a scanning grating spectrometer (Model 6500; NIRSystems, University Park, PA) and a 2-in round cup with quartz window by the Crop Quality Laboratory at Penn State University. Calibration samples (100 from each experiment) were analyzed for N with the Dumas combustion method with an NA15000 Elemental Analyzer (Carlo Erba, University Park, PA) (Horneck and Miller, 1998) and for NDF and IVTD by the Ankom filter bag methods (Ankom Technology, Fairport, NY). Ruminal fluid was collected from one cannulated cow (Bos taurus) offered orchardgrass and alfalfa (Medicago sativa L.) hay. Calibration statistics for CP estimation were SECV = 1.07, bias = – 0.20, SEC(C) = 1.07, R² = 0.959, where SECV is the standard error for cross validation and SEC(C) is the standard error for calibration uncorrected for bias. Calibration statistics for NDF_Ankom estimation were SECV = 2.76, bias = – 0.75, SEC(C) = 2.62, R² = 0.94. Calibration statistics for IVTD_Ankom estimation were SECV = 1.85, bias = negligible, SEC(C) = 1.85, RSQ = 0.94.

	RESULTS AND DISCUSSION

TOP NOTES ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS AND DISCUSSION CONCLUSIONS REFERENCES

 
Experiment 1: Herbage Nutritive Value of Different Chicory and Plantain Cultivars
Differences in nutritive value among cultivars of chicory, plantain, and Pennlate orchardgrass were observed in the year of establishment and in the subsequent year (Table 1). The differences in CP concentration were more apparent at the beginning (May 1998) than at the end of the grazing season, having an average 20% higher CP concentration in the forbs than the grass. In May 1998, the chicory cultivars had an average CP concentration of 217 g kg^–1, whereas orchardgrass had 173 g kg^–1 (P < 0.05). Of the plantain cultivars, only Tonic had a higher CP than Pennlate orchardgrass (210 vs. 173 g kg^–1, respectively, P < 0.05). For the remainder of the grazing season, the differences observed were not significant. However, a slight increase in CP was observed in all cultivars from October 1997 onward; this was probably related to our fertilization schedule. Changes in growth rate could have also affected CP.

The NDF concentration in chicory and plantain herbage was significantly lower than that of Pennlate orchardgrass in the year of establishment and the following year (Table 1). Average NDF concentration of 260 g kg^–1 were observed in October 1997, but the average concentration increased to values above 300 g kg^–1 in the following year. This increase was probably related to their reproductive habits because a low percentage of plants flowered within the year of establishment (data not shown). The highest values were observed in May, when the average fiber concentrations of chicory, plantain, and orchardgrass were 381, 391, and 545 g kg^–1, respectively.

In their study comparing Puna chicory and Pennlate orchardgrass under different cutting management, Holden et al. (2000) reported NDF values of 207 g kg^–1 and 506 g kg^–1 for the chicory and the grass, respectively. Waugh et al. (1998) reported NDF values of grazed Puna chicory of 255 g kg^–1 during a 1-wk trial in the summer and 198 g kg^–1 in the fall. The authors of both papers suggested that even though the lower NDF concentration of Puna chicory should allow for higher DM intakes, these levels could be too low to reach adequate rumen health and/or maximum yield production. In our study under cutting (Sanderson et al., 2003) and in the current study, NDF concentrations of chicory were in all cases greater than those reported by these authors.

The IVTD of the three chicory cultivars (Table 1) was on average between 4 and 6% greater than that of Pennlate orchardgrass in May (896 vs. 863 g kg^–1, respectively; P < 0.05) and October 1998 (905 vs. 853 g kg^–1, respectively; P < 0.05). In August 1998, their IVTD did not differ (894 vs. 885 g kg^–1, respectively), which was due to a more negative effect of infrequently and lightly grazed treatments on the IVTD of Puna chicory and Lancelot plantain (793 and 769 g kg^–1, respectively) than for orchardgrass (858 g kg^–1, complete data set not shown). Information presented by McCoy et al. (1997) suggests that, at least for Puna chicory, these results may be related to differences in the IVTD of pasture strata.

The IVTD of the plantain cultivars was not greater than that of Pennlate orchardgrass in any of the harvest dates (857 vs. 867 g kg^–1 average over the year, respectively). Reported IVTD values for naturally occurring plantain species are 804 g kg^–1 (Derrick et al., 1993), but no additional reports are available concerning plantain under rotational grazing conditions. Wilman and Riley (1993) and Stewart (1996) suggest that the effect of plantain on rumen microflora (i.e., slowing down the breakdown of the material) affects the results obtained by the conventional methods of IVTD analysis. The authors advise that a similar method to that used in this work may judge against plantain when compared with other forages.

Experiment 1: Nutritive Value as Affected by Grazing
Only in Exp. 1 (Table 2) did grazing treatment have a significant effect on nutritive value. Crude protein concentrations and IVTD of herbage were affected by the combinations of frequency and intensity of grazing used in Exp. 1. However, no significant effect of management level was observed on NDF concentration. No significant interaction between species and grazing management was observed. The effects of grazing or cutting frequency on nutritive value of the species were also observed by Sanderson et al. (2003) and Holden et al. (2000). The frequency with which the pastures were grazed in August had a more prominent effect on the CP concentration of herbage than did the intensity. The difference between grazing every 3 wk or every 5 wk was almost 20% (229 vs. 189 g kg^–1, P < 0.01). Holden et al. (2000) observed differences of up to 34% in more frequently clipped plots (225, 166, and 149 g kg^–1 on the frequent, moderate, and less frequent harvest, respectively; average over 2 yr).

Experiment 2: Herbage Nutritive Value of Puna Chicory and Lancelot Plantain
Results for herbage CP concentration for Exp. 2 (Table 3) were slightly different than what was observed in Exp. 1 (Table 1). The CP concentration of Puna chicory and Lancelot plantain in May (average over both years of study) were similar to those of orchardgrass (174, 161, and 165 g kg^–1, respectively). In August, the CP concentration of Puna chicory was greater than orchardgrass (191 vs. 179 g kg^–1, P < 0.05). Lancelot plantain did not differ from orchardgrass in CP. The CP concentrations observed in 2001 were slightly lower than those observed in 2000, and, even though no attempts of statistical comparison between experiments should be made, 1998 values were also numerically higher (182.5, 165, and 199 g kg^–1, average of shared entries for 2000, 2001, and 1998, respectively). Jung et al. (1996) proposed potential CP values for Puna chicory and Pennlate orchardgrass greater than 250 g kg^–1 and related lower values to floral stem production.

Leaf-to-stem ratios (Table 5) of Puna chicory and Lancelot plantain herbage in spring 2001 were one half the ratio in 2000 (P < 0.001 for year comparison). In August, the leaf-to-stem ratio of Puna chicory was less than a quarter in 2001 of what was observed in 2000 (P < 0.05), whereas the corresponding ratio for plantain herbage between years was similar (10.6 average between 2000 and 2001). The composition of the herbage of Pennlate orchardgrass in May was also different between years, but the relation was opposite. The proportion of leaves over stems was 4.4 in 2000 and 25.0 in 2001 (P < 0.05), whereas in August the herbage was composed of leaves only.

The nutritive values of most forage species vary over time. This variation can be associated with reproductive stages and maturity of plant parts (Buxton et al., 1985) and with the effects of grazing animals caused by treading and dung and urine depositions (Matches, 1992). Reproductive stages of Pennlate orchardgrass occur early in the spring, whereas chicory and plantain may flower later in the spring and summer (Castellano-Cantero, 1997; Stewart, 1996). It is possible that differences in the timing to reproductive development are associated with nutritive values observed because most differences between the forbs and orchardgrass occurred in May. However, the results of Exp. 2 suggest that continuous reproductive development of chicory and plantain does not negatively affect the nutritive value of the herbage produced when the pastures are grazed intensively during the spring. In the case of forage chicory, the presence of some young reproductive stems may help prevent effective fiber deficiencies of herbage for high-yield lactating cows (Holden et al., 2000).

	CONCLUSIONS

TOP NOTES ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS AND DISCUSSION CONCLUSIONS REFERENCES

 
Results of 3 yr of study of chicory and plantain cultivars under different grazing conditions suggest that most of the tested cultivars have acceptable nutritive values, similar to that of Pennlate orchardgrass. In previous reports (Sanderson et al., 2003a; Labreveux et al., 2004), it was suggested that even though Puna chicory would not consistently exceed the productivity levels of Pennlate orchardgrass, their growth rates and times to grazing were offset and could complement each other on a farm scale. Nutritive values reported here suggest that there could be an advantage to this approach, especially to reduce the total fiber content of grass-based diets. It was also found that our recommendations to use a canopy-height–based grazing strategy to maximize yield and persistence of Puna chicory and Lancelot plantain does not compromise their nutritive value. As opposed to what could be deduced from the literature, the impact of continuous reproductive development of chicory and plantain did not directly affect the nutritive value of the forage produced when the pastures were grazed intensively during the spring.

	ACKNOWLEDGMENTS

 
The authors would like to thank Mr. Jerry Elwinger for his suggestions on statistical matters and the Penn State University students involved in the project.

	NOTES

TOP NOTES ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS AND DISCUSSION CONCLUSIONS REFERENCES

 
Mention of a trademark does not imply endorsement.

	REFERENCES

TOP NOTES ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS AND DISCUSSION CONCLUSIONS REFERENCES

 

• Belesky, D.P., J.M. Fedders, K.E. Turner, and J.M. Ruckle. 1999. Productivity, botanical composition and nutritive value of swards including forage chicory. Agron. J. 91:450–456.[Abstract/Free Full Text]
• Belesky, D.P., J.M. Ruckle, and W.M. Clapham. 2004. Dry-matter production, allocation, and nutritive value of forage chicory cultivars as a function of nitrogen. J. Agron. Crop Sci. 190:100–110.
• Belesky, D.P., K.E. Turner, J.M. Fedders, and J.M. Ruckle. 2001. Mineral composition of swards containing forage chicory. Agron. J. 93:468–475.[Abstract/Free Full Text]
• Belesky, D.P., K.E. Turner, and J.M. Ruckle. 2000. Influence of nitrogen on productivity and nutritive value of forage chicory. Agron. J. 92:472–478.[Abstract/Free Full Text]
• Burns, J.C., D.S. Chamblee, and F.G. Giesbrecht. 2002. Defoliation intensity effects on season-long dry matter distribution and nutritive value of tall fescue. Crop Sci. 42:1274–1284.[Abstract/Free Full Text]
• Buxton, D.R., J.S. Hornstein, W.F. Wedin, and G.C. Marten. 1985. Forage quality in stratified canopies of alfalfa, birdsfoot trefoil, and red clover. Crop Sci. 25:273–279.[Abstract/Free Full Text]
• Castellano-Cantero, F.U. 1997. Aspects related to seed production of the chicory (Cichorium intybus L.) cultivar INIA Lacerta. (In Spanish.) Tesis Ingeniero Agrónomo. Univ. de la República, Facultad de Agronomía, Montevideo, Uruguay.
• Collins, M., and J.E. McCoy. 1997. Chicory productivity forage quality, and response to nitrogen fertilization. Agron. J. 89:232–238.[Abstract/Free Full Text]
• Derrick, R.W., G. Mosely, and D. Wilman. 1993. Intake by sheep and digestibility of chickweed, dandelion, dock, ribwort, and spurrey compared with perennial ryegrass. J. Agric. Sci. 120:51–61.
• Foster, J.G., J.M. Fedders, W.M. Clapham, J.W. Robertson, D.P. Bligh, and K.E. Turner. 2002. Nutritive value and animal selection of forage chicory cultivars grown in Central Appalachia. Agron. J. 94:1034–1042.[Abstract/Free Full Text]
• Fraser, T.J., and J.S. Rowarth. 1996. Legumes, herbs or grass for lamb performance? Proc. N.Z. Grassl. Assoc. 58:49–52.
• García, F., P. Carrère, J.F. Soussana, and R. Baumont. 2003. How do severity and frequency of grazing affect sward characteristics and the choices of sheep during the grazing season? Grass Forage Sci. 58:138–150.
• Griffiths, W.M., J. Hogdson, and G.C. Arnold. 2003. The influence of sward canopy structure on foraging decisions by grazing cattle: I. Patch selection. Grass Forage Sci. 58:112–124.
• Holden, L.A., G.A. Varga, G.A. Jung, and J.A. Shaffer. 2000. Comparison of ‘Grasslands Puna’ chicory and orchardgrass for multiple harvests at different management levels. Agron. J. 92:191–194.[Abstract/Free Full Text]
• Horneck, D.A., and R.O. Miller. 1998. Determination of total nitrogen in plant tissue. p. 75–83. In Y.P. Karla (ed.) Handbook of reference methods for plant analysis. CRC Press, Boca Raton, FL.
• Hoskin, S.O., T.N. Barry, P.R. Wilson, W.A.G. Charleston, and J. Hogdson. 1999. Effects of reducing anthelmintic input upon growth and faecal egg and larval counts in young farmed deer grazing chicory (Cichorium intybus) and perennial ryegrass (Lolium perenne)/white clover (Trifolium repens) pasture. J. Agric. Sci. 132:335–345.[CrossRef]
• Jung, G.A., J.A. Shaffer, G.A. Varga, and J.R. Everhart. 1996. Performance of ‘Grasslands Puna’ chicory at different management levels. Agron. J. 88:104–111.[Abstract/Free Full Text]
• Kuiper, P.J.C., and M. Bos (ed.). 1992. Plantago: A multidisciplinary study. Springer-Verlag, Berlin Heidelberg.
• Kusmartono, A. Shimada, and T.N. Barry. 1997. Rumen digestion and rumen outflow rate in deer fed fresh chicory (Cichorium intybus) or perennial ryegrass (Lolium perenne). J. Agric. Sci. 128:87–94.
• Labreveux, M., M.H. Hall, and M.A. Sanderson. 2004. Productivity of chicory and plantain cultivars under grazing. Agron. J. 96:710–716.[Abstract/Free Full Text]
• Li, G.D., P.D. Kemp, and J. Hogdson. 1997. Regrowth, morphology and persistence of Grasslands Puna chicory (Cichorium intybus L.) in response to grazing frequency and intensity. Grass Forage Sci. 52:33–41.[CrossRef]
• Littel, R.C., P.R. Henry, and C.B. Ammerman. 1998. Statistical analysis of repeated measures data using SAS procedures. J. Anim. Sci. 76:1216–1231.[Abstract/Free Full Text]
• Littel, R.C., G.A. Miliken, W.W. Stroup, and R.D. Wolfinger. 1996. SAS System for mixed models. SAS Inst., Cary, NC.
• Matches, A.G. 1992. Plant response to grazing: A review. J. Prod. Agric. 5:1–7.
• McCoy, J.E., M. Collins, and C.T. Dougherty. 1997. Amount and quality of chicory herbage ingested by grazing cattle. Crop Sci. 37:239–242.[Abstract/Free Full Text]
• Min, B.R., T.N. Barry, P.R. Wilson, and P.D. Kemp. 1997. The effects of grazing chicory (Cichorium intybus) and birdsfoot trefoil (Lotus corniculatus) on venison and velvet production by young red and hybrid deer. N. Z. J. Agric. Res. 40:335–347.
• New Zealand Pastoral Agriculture Research Institute Ltd. 1996. Variety: ‘Grasslands Lancelot’. Application no. 96/016. Plant Varieties J. 9:39–40.
• Pyne Gould Guinness Ltd. 1996. Variety: ‘Ceres Tonic’ syn ‘PG 30’. Application no. 96/017. Plant Varieties J. 9:39.
• Rumball, W., R.G. Keogh, G.E. Lane, J.E. Miller, and R.B. Claydon. 1997. "Grasslands Lancelot" plantain (Plantago lanceolata L.). N. Z. J. Agric. Res. 40:373–377.
• Sanderson, M.A., M. Labreveux, M.H. Hall, and G.F. Elwinger. 2003a. Forage yield and persistence of chicory and English plantain. Crop Sci. 43:995–1000.[Abstract/Free Full Text]
• Sanderson, M.A., M. Labreveux, M.H. Hall, and G.F. Elwinger. 2003b. Nutritive value of chicory and English plantain forage. Crop Sci. 43:1797–1894.[Abstract/Free Full Text]
• SAS Institute. 1998. SAS user's guide: Statistics. 7th ed. SAS Inst., Cary, NC.
• Scehovic, J., and B. Jeangros. 1994. A new index for assessing the effects of the botanical composition of permanent pastures on forage quality. (In French with English abstract.) Rev. Suisse Agric. 26:167–170.
• Skinner, R.H., and D.L. Gustine. 2002. Freezing tolerance of chicory and narrow-leaf plantain. Crop Sci. 42:2038–2043.[Abstract/Free Full Text]
• Steel, R.G.D., J.H. Torrie, and D.A. Dickey. 1997. Principles and procedures of statistics. A biometrical approach. 3rd ed. McGraw-Hill Co., New York.
• Stevens, D.R., and I.D. Corson. 2003. Optimizing calf growth of red deer in summer and autumn. Proc. N.Z. Soc. Anim. Prod. 63:218–221.
• Stewart, A.V. 1996. Plantain (Plantago lanceolata): A potential pasture species. Proc. N.Z. Grassl. Assoc. 58:77–86.
• Tracy, B.F., and M.A. Sanderson. 2004. Forage productivity, species evenness and weed invasion in pasture communities. Agric. Ecosyst. Environ. 102:175–183.[CrossRef]
• Volesky, J.D. 1996. Forage production and grazing management of chicory. J. Prod. Agric. 9:403–406.
• Waugh, C.D., D.A. Clark, S.L. Harris, E.R. Thom, P.J.A. Copeman, and A.R. Napper. 1998. Chicory for milk production. Proc. N.Z. Grassl. Assoc. 60:33–37.
• Wilman, D., and J.A. Riley. 1993. Potential nutritive value of a wide range of grassland species. J. Agric. Sci. 120:43–49.

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