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Journal of the Australian Rangeland Society
RESEARCH FRONT

The patterns of grazed pasture associated with scattered trees across an Australian temperate landscape: an investigation of pasture quantity and quality

Phoebe Barnes A B F , Brian R. Wilson A C , Mark G. Trotter B , David W. Lamb B , Nick Reid A , Terry Koen D and Leopold Bayerlein E
+ Author Affiliations
- Author Affiliations

A School of Environmental and Rural Science, University of New England, Armidale, NSW 2351, Australia.

B Precision Agricultural Research Group, University of New England, Armidale, NSW 2351, Australia.

C NSW Department of Environment, Climate Change and Water, PO Box U221, Armidale, NSW 2351, Australia.

D NSW Department of Environment, Climate Change and Water, PO Box 445, Cowra 2794, Australia.

E School of Business, Economics and Public Policy, University of New England, Armidale, NSW 2351, Australia.

F Corresponding author. Email: pbarnes@une.edu.au

The Rangeland Journal 33(2) 121-130 https://doi.org/10.1071/RJ10068
Submitted: 29 October 2010  Accepted: 21 February 2011   Published: 22 June 2011

Abstract

Scattered paddock trees occur across agricultural landscapes in Australia. However, in the temperate regions of Australia their numbers are rapidly declining and they may be lost across much of the landscape in 200 years. Here we examined the spatial distribution of green (GDB), senescent (SDB) and total (TDB) dry pasture biomass, and nutrient status of the GDB fraction around scattered Eucalyptus trees on three parent materials (basalt, granite and meta-sediment) in native and sown pastures across a range of grazed temperate landscapes in northern New South Wales. We used a combination of destructive harvests and a handheld active optical canopy reflectance sensor (AOS) with an integrated GPS to examine pasture biomass around scattered trees. The harvested pasture biomass data indicated that under grazed conditions the presence of scattered trees did not introduce significant radial trends in TDB or GDB out to a distance of 3.5 canopy radii regardless of tree species or parent material. The red and near-infrared reflectance-based Normalised Difference Vegetation Index (NDVI), as measured by the AOS, did indicate a consistent azimuthal trend with larger GDB on the southern side of the tree and lower GDB on the northern side in the native pasture. However, this observation must be qualified as the regression coefficient for the relationship between NDVI and GDB was significant but weak (best r2 = 0.42), and SDB reduced its predictive capacity. We also found a higher percentage of GDB under the canopy than in the open paddock. We suggest that the combination of these results may indicate higher grazing pressure under trees than in the open paddock. Pasture nutrient concentration (P, K and S) was higher in both native and sown pastures beneath the tree canopy compared with the open paddock. This study indicates that, in this temperate environment, scattered trees do not adversely affect pasture production, and that they can improve some pasture nutrients.

Additional keywords: eucalypt, green pasture biomass, Normalised Difference Vegetation Index, proximal sensing, senescent pasture biomass.


References

Alcock, D. (2007). How useful are blocks and dry licks for livestock in a drought? NSW DRI Primefacts No. 375, Cooma, NSW.

Anderson, D. L., and Henderson, L. J. (1986). Sealed chamber digestion for plant nutrient analysis. Agronomy Journal 78, 937–938.
Sealed chamber digestion for plant nutrient analysis.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL28XlvVOisrk%3D&md5=c429ea0d5a574517c24994ad42ef4ac1CAS |

Andrews, S. (2007). Engineered woodlands. The ‘Lakeview’ demonstration/trial at Uralla. LandChat 61. SNELCC.

Ayala Torales, A. T., Acosta, G. L., Deregibus, V. A., and Moauro, P. M. (2000). Effects of grazing frequency on the production, nutritive value, herbage utilisation, and structure of Paspalum dilatatum sward. New Zealand Journal of Agricultural Research 43, 467–472.
Effects of grazing frequency on the production, nutritive value, herbage utilisation, and structure of Paspalum dilatatum sward.Crossref | GoogleScholarGoogle Scholar |

Baker, B. S., Eynden, T. V., and Boggess, N. (1981). Hay yield determinations of mixed swards using a disk meter. Agronomy Journal 73, 67–69.
Hay yield determinations of mixed swards using a disk meter.Crossref | GoogleScholarGoogle Scholar |

Barnes, P., Wilson, B. R., Nadolny, C., and Growns, I. (2009). The influence of individual native trees and grazing regime on soil properties and groundcover patterns in a temperate landscape of New South Wales, Australia. The Rangeland Journal 31, 405–415.
The influence of individual native trees and grazing regime on soil properties and groundcover patterns in a temperate landscape of New South Wales, Australia.Crossref | GoogleScholarGoogle Scholar |

Belsky, A. J. (1992). Effects of trees on nutritional quality of understorey gramineous forage in tropical savannas. Tropical Grasslands 26, 12–20.

Belsky, A. J. (1994). Influences of trees on savanna productivity: tests of shade, nutrients, and tree-grass competition. Ecology 75, 922–932.
Influences of trees on savanna productivity: tests of shade, nutrients, and tree-grass competition.Crossref | GoogleScholarGoogle Scholar |

Belsky, A., Mwonga, S., Amundson, R., Duxbury, J., and Ali, A. (1993). Comparative effects of isolated trees on their undercanopy environments in high- and low-rainfall savannas. Journal of Applied Ecology 30, 143–155.
Comparative effects of isolated trees on their undercanopy environments in high- and low-rainfall savannas.Crossref | GoogleScholarGoogle Scholar |

Bird, P., Bicknell, D., Bulman, P., Burke, S., Leys, J., and Parker, J. (1992). The role of shelter in Australia for protecting soils, plants and livestock. Agroforestry Systems 20, 59–86.
The role of shelter in Australia for protecting soils, plants and livestock.Crossref | GoogleScholarGoogle Scholar |

Bureau of Meteorology (2009). ‘Averages for Armidale (Tree Group Nursery) – Climate Averages for Australian Sites.’ (Australian Government) Available at: www.bom.gov.au/climate/averages/tables/cw_056002.shtml

Campbell, N. A., and Arnold, G. W. (1973). The visual assessment of pasture yield. Australian Journal of Experimental Agriculture and Animal Husbandry 13, 263–267.
The visual assessment of pasture yield.Crossref | GoogleScholarGoogle Scholar |

Christie, E. K. (1975). A note on the significance of Eucalyptus populnea for buffel grass production in infertile semi-arid rangelands. Tropical Grasslands 9, 243–246.

Clarke, P. J. (2003). Composition of grazed and cleared temperate grassy woodlands in eastern Australia: patterns in space and inference in time. Journal of Vegetation Science 14, 5–14.
Composition of grazed and cleared temperate grassy woodlands in eastern Australia: patterns in space and inference in time.Crossref | GoogleScholarGoogle Scholar |

Dahlgren, R. A., Horwath, W. R., Tate, K. W., and Camping, T. J. (2003). Blue oak enhance soil quality in California oak woodlands. California Agriculture 57, 42–47.
Blue oak enhance soil quality in California oak woodlands.Crossref | GoogleScholarGoogle Scholar |

Durr, P. A., and Rangel, J. (2002). Enhanced forage production under Samanea in a subhumid tropical grassland. Agroforestry Systems 54, 99–102.
Enhanced forage production under Samanea in a subhumid tropical grassland.Crossref | GoogleScholarGoogle Scholar |

Ebersohn, J. P., and Lucas, P. (1965). Trees and soil nutrients in south-western Queensland. Queensland Journal of Agricultural and Animal Sciences 22, 431–435.
| 1:CAS:528:DyaF2sXhvFei&md5=f5152f583c44edc069bdf81aefe59b7aCAS |

Ganguli, A. C., Vermeire, L. T., Mitchell, R. B., and Wallace, M. C. (2000). Comparison of four nondestructive techniques for estimating standing crop in shortgrass plains. Agronomy Journal 92, 1211–1215.
Comparison of four nondestructive techniques for estimating standing crop in shortgrass plains.Crossref | GoogleScholarGoogle Scholar |

Genstat (2009). ‘The Guide to Genstat Release 12. Part 2: Statistics.’ (VSN International: Hemel Hempstead, Hertfordshire, UK.)

Gibbons, P., Lindenmayer, D. B., Fischer, J., Manning, A. D., Weinberg, A., Seddon, J., Ryan, P., and Barrett, G. (2008). The future of scattered trees in agricultural landscapes. Conservation Biology 22, 1309–1319.
The future of scattered trees in agricultural landscapes.Crossref | GoogleScholarGoogle Scholar | 1:STN:280:DC%2BD1cnoslGiuw%3D%3D&md5=898f585a1ac3add0be132db60a20a37aCAS | 18680500PubMed |

Goh, K. M., Mansur, I., Mead, D. J., and Sweet, G. B. (1996). Biological nitrogen fixing capacity and biomass production of different understorey pastures in a Pinus radiata-pasture agroforestry system in New Zealand. Agroforestry Systems 34, 33–49.
Biological nitrogen fixing capacity and biomass production of different understorey pastures in a Pinus radiata-pasture agroforestry system in New Zealand.Crossref | GoogleScholarGoogle Scholar |

Gong, P., Pu, R., Biging, G. S., and Larrieu, M. R. (2003). Estimation of forest leaf area index using vegetation indices derived from hyperion hyperspectral data. IEEE Transactions on Geoscience and Remote Sensing 41, 1355–1362.
Estimation of forest leaf area index using vegetation indices derived from hyperion hyperspectral data.Crossref | GoogleScholarGoogle Scholar |

Harmoney, K. R., Moore, K. J., George, R. J., Brummer, C. E., and Russell, J. R. (1997). Determination of pasture biomass using four indirect methods. Agronomy Journal 89, 665–672.
Determination of pasture biomass using four indirect methods.Crossref | GoogleScholarGoogle Scholar |

Inman, D., and Khosla, R. (2005). On-the-go active remote sensing for efficient crop nitrogen management. Sensor Review 25, 209–214.
On-the-go active remote sensing for efficient crop nitrogen management.Crossref | GoogleScholarGoogle Scholar |

Isbell, R. F. (2002). ‘The Australian Soil Classification.’ Rev. edn. (CSIRO Publishing: Melbourne.)

Jackson, J., and Ash, A. (1998). Tree-grass relationships in open eucalypt woodlands of north eastern Australia: influence of trees on pasture productivity, forage quality and species distribution. Agroforestry Systems 40, 159–176.
Tree-grass relationships in open eucalypt woodlands of north eastern Australia: influence of trees on pasture productivity, forage quality and species distribution.Crossref | GoogleScholarGoogle Scholar |

Jackson, J., and Ash, A. (2001). The role of trees in enhancing soil nutrient availability for native perennial grasses in open eucalypt woodlands of north-east Queensland. Australian Journal of Agricultural Research 52, 377–386.
The role of trees in enhancing soil nutrient availability for native perennial grasses in open eucalypt woodlands of north-east Queensland.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXisVGksbc%3D&md5=860fb992d49feba78e983e7cd71e6c55CAS |

Ko, L. J., and Reich, P. B. (1993). Oak tree effects on soil and herbaceous vegetation in savannas and pastures in Wisconsin. American Midland Naturalist 130, 31–42.
Oak tree effects on soil and herbaceous vegetation in savannas and pastures in Wisconsin.Crossref | GoogleScholarGoogle Scholar |

Laca, E. A. (2009). New approaches and tools for grazing management. Rangeland Ecology and Management 62, 407–417.
New approaches and tools for grazing management.Crossref | GoogleScholarGoogle Scholar |

Le Brocque, A. F., Goodhew, K. A., and Zammit, C. A. (2009). Overstorey tree density and understorey regrowth effects on plant composition, stand structure and floristic richness in grazed temperate woodlands in eastern Australia. Agriculture, Ecosystems & Environment 129, 17–27.
Overstorey tree density and understorey regrowth effects on plant composition, stand structure and floristic richness in grazed temperate woodlands in eastern Australia.Crossref | GoogleScholarGoogle Scholar |

Lodge, G. M., and Whalley, R. D. B. (1989). Native and natural pastures on the Northern Slopes and Tablelands of New South Wales: a review and annotated bibliography. NSW Agriculture and Fisheries Technical Bulletin 35, 1–49.

Ludwig, F., de Kroon, H., and Prins, H. H. T. (2008). Impacts of savanna trees on forage quality for a large African herbivore. Oecologia 155, 487–496.
Impacts of savanna trees on forage quality for a large African herbivore.Crossref | GoogleScholarGoogle Scholar | 18309522PubMed |

Ludwig, F., de Kroon, H., Prins, H. H. T., and Berendse, F. (2001). Effects of nutrients and shade on tree-grass interaction in an East African savanna. Journal of Vegetation Science 12, 579–588.
Effects of nutrients and shade on tree-grass interaction in an East African savanna.Crossref | GoogleScholarGoogle Scholar |

Manning, A. D., Fischer, J., and Lindenmayer, D. B. (2006). Scattered trees are keystone structures – implications for conservation. Biological Conservation 132, 311–321.
Scattered trees are keystone structures – implications for conservation.Crossref | GoogleScholarGoogle Scholar |

Martin, R. C., Astatkie, T., Cooper, J. M., and Fredeen, A. H. (2005). A comparison of methods used to determine biomass on naturalized swards. Journal of Agronomy & Crop Science 191, 152–160.
A comparison of methods used to determine biomass on naturalized swards.Crossref | GoogleScholarGoogle Scholar |

McPherson, G. R., Rasmussen, A. G., Wester, D. B., and Masters, R. A. (1991). Vegetation and soil zonation associated with Juniperus pinchotti Sudw. trees. Western North American Naturalist 51, 316–324.

Mitchell, A. R., Pinter, P. J., Guerrero, J. N., Hernandez, C. B., and Marble, V. L. (1990). Spectral reflectance measurements of alfalfa under sheep grazing. Agronomy Journal 82, 1098–1103.
Spectral reflectance measurements of alfalfa under sheep grazing.Crossref | GoogleScholarGoogle Scholar |

Oliver, I., Pearce, S., Greenslade, P. J. M., and Britton, D. R. (2006). Contribution of paddock trees to the conservation of terrestrial invertebrate biodiversity within grazed native pastures. Austral Ecology 31, 1–12.
Contribution of paddock trees to the conservation of terrestrial invertebrate biodiversity within grazed native pastures.Crossref | GoogleScholarGoogle Scholar |

Omer, R. M., Hester, A. J., Gordon, I. J., Swain, M. D., and Raffique, S. M. (2006). Seasonal changes in pasture biomass, production and offtake under the transhumance system in northern Pakistan. Journal of Arid Environments 67, 641–660.
Seasonal changes in pasture biomass, production and offtake under the transhumance system in northern Pakistan.Crossref | GoogleScholarGoogle Scholar |

Reid, N., and Landsberg, J. (2000). Tree decline in agricultural landscapes: what we stand to lose. In: ‘Temperate Eucalypt Woodlands in Australia: Biology, Conservation, Management and Restoration’. (Eds R. J. Hobbs and C. J. Yates.) pp. 127–166. (Surrey Beatty and Sons: Chipping Norton, NSW.)

Rouse, J. W., Haas, J. R., Schell, J. A., and Deering, D. W. (1974). Monitoring vegetation systems in the great plains with ERTS. In: ‘Third Earth Resources Technology Satellite-1 Symposium’. NASA. (Eds S. Freden, E. Mercanti and M. Becker.) pp. 309–317. (US Government Printing Office: Washington, DC.)

Sánchez-Jardón, L., Acosta, B., del Pozo, A., Casado, M. A., Ovalle, C., Elizalde, H. F., Hepp, C., and de Miguel, J. M. (2010). Grassland productivity and diversity on a tree cover gradient in Nothofagus pumilio in NW Patagonia. Agriculture, Ecosystems & Environment 137, 213–218.
Grassland productivity and diversity on a tree cover gradient in Nothofagus pumilio in NW Patagonia.Crossref | GoogleScholarGoogle Scholar |

Sangha, K. K., Midmore, D. J., Rolfe, J., and Jalota, R. K. (2005). Tradeoffs between pasture production and plant diversity and soil health attributes of pasture systems of central Queensland, Australia. Agriculture, Ecosystems & Environment 111, 93–103.
Tradeoffs between pasture production and plant diversity and soil health attributes of pasture systems of central Queensland, Australia.Crossref | GoogleScholarGoogle Scholar |

Scholes, R. J., and Archer, S. R. (1997). Tree–grass interactions in savannas. Annual Review of Ecology Evolution and Systematics 28, 517–544.
Tree–grass interactions in savannas.Crossref | GoogleScholarGoogle Scholar |

Senft, R. L., Rittenhouse, L. R., and Woodmansee, R. G. (1985). Factors influencing patterns of cattle grazing behaviour on shortgrass steppe. Journal of Range Management 38, 82–87.
Factors influencing patterns of cattle grazing behaviour on shortgrass steppe.Crossref | GoogleScholarGoogle Scholar |

Sharrow, S. H. (1991). Tree planting pattern on forage production in a Douglas-fir agroforest. Agroforestry Systems 16, 167–175.
Tree planting pattern on forage production in a Douglas-fir agroforest.Crossref | GoogleScholarGoogle Scholar |

SPSS Inc. (2009). ‘PASW Statistics 18.0.0.’ (SPSS: Chicago, IL.)

Sudmeyer, R., Bicknell, D., and Coles, N. (2007). Tree windbreaks in the wheatbelt. Bulletin 4723, State of Western Australia, Department of Agriculture and Food, Western Australia.

Trotter, M. G., Lamb, D. W., Donald, G. E., and Schneider, D. A. (2010). Evaluating an active optical sensor for quantifying and mapping green herbage mass and growth in a perennial grass pasture. Crop & Pasture Science 61, 389–398.
Evaluating an active optical sensor for quantifying and mapping green herbage mass and growth in a perennial grass pasture.Crossref | GoogleScholarGoogle Scholar |

Trotter, T. F., Frazier, P. S., Trotter, M. G., and Lamb, D. W. (2008). Objective biomass assessment using an active plant sensor (CropCircle) – preliminary experiences on a variety of agricultural landscapes. In: ‘Ninth International Conference on Precision Agriculture’. Denver, Colorado. (Ed. R. Khosla.) (Colorado State University: Fort Collins, CO.)

Van Soest, P. J. (1994). ‘Nutrient Ecology of the Ruminant.’ 2nd edn. (Cornell University Press: Ithaca, NY.)

Walker, J., Moore, R. M., and Robertson, J. A. (1972). Herbage response to tree and shrub thinning in Eucalyptus populnea shrub woodlands. Australian Journal of Agricultural Research 23, 405–410.
Herbage response to tree and shrub thinning in Eucalyptus populnea shrub woodlands.Crossref | GoogleScholarGoogle Scholar |

Whelan, B. M., McBratney, A. B., and Minasny, B. (2001). Vesper-spatial prediction software for precision agriculture. In: ‘Third European Conference on Precision Agriculture’. Montpellier, France. (Eds G. Grenier and S. Blackmore.) pp. 139–144. (Agro-Montpellier: France.)

Wilson, B., Growns, I., and Lemon, J. (2007). Scattered native trees and soil patterns in grazing land on the Northern Tablelands of New South Wales, Australia. Australian Journal of Soil Research 45, 199–205.
Scattered native trees and soil patterns in grazing land on the Northern Tablelands of New South Wales, Australia.Crossref | GoogleScholarGoogle Scholar |

Wilson, B. R. (2002). Influence of scattered paddock trees on surface soil properties: a case study of the Northern Tablelands of NSW. Ecological Management & Restoration 3, 211–219.
Influence of scattered paddock trees on surface soil properties: a case study of the Northern Tablelands of NSW.Crossref | GoogleScholarGoogle Scholar |

Wilson, S. M., Whitham, J. A. H., Bhati, U. N., Horvath, D., and Tran, Y. D. (1995). Survey of trees on Australian Farms: 1993–94. ABARE Research Report 95.7, Canberra.

Wong, C. C., and Wilson, J. R. (1980). Effects of shading on the growth and nitrogen content of green panic and siratro in pure and mixed swards defoliated at two frequencies. Australian Journal of Agricultural Research 31, 269–285.
Effects of shading on the growth and nitrogen content of green panic and siratro in pure and mixed swards defoliated at two frequencies.Crossref | GoogleScholarGoogle Scholar |