Overview of Common Pasture Grasses in New Zealand

Objective of the Lecture

• Describe common pasture grasses in New Zealand, focused on unsown species.
• Discuss identification, form, function, adaptation, and challenges to the grasses.
• Highlight climatic factors (temperature, moisture) and edaphic factors (soil fertility, grazing tolerance, pest challenges).
• Explore nutritional values and relative yields of grasses.

Key Concepts

• Importance of Plant Identification
  • Essential for recognizing pasture species.
  • Useful resources: Pasture Plant Identification website, Grass View by University of Nottingham.

Common Pasture Grasses

1. Annual Paua (Poa annua)

• Species Type: True annual grass.
• Identification: Canoe-shaped leaf tip, parallel "tram lines" on leaf blades.
• Coloration: Light green with possible leaf wrinkling.

2. Barley Grass (Hordeum murinum)

• Species Type: True annual grass.
• Characteristics: Good winter growth; flowers early in spring.
• Seed Dispersal Mechanism: Sticky horns attach to socks, wool, and animals.

3. Blue Wheat Grass (Anthosachne xylandri)

• Species Type: Native, non-tussock forming.
• Habitat: Found in Canberra Hill Country and Canterbury High Country.

4. Brown Top (Agrostis capillaris)

• Species Type: Perennial, low fertility grass.
• Habitat: Moist hill country and drier East Coast regions.
• Reproductive Features: Early flowering in spring, known for brown seed heads.

5. Kooch (Cynodon dactylon)

• Species Type: Wheatgrass family; perennial weed in pastures.
• Characteristics: Non-hairy, palatable leaves, spreads via rhizomes.

6. Creeping Bent (Agrostis stolonifera)

• Species Type: Perennial grass, similar to brown top.
• Characteristics: Distinct ligule; spreads with rhizomes.

7. Crested Dog's Tail (Cynosurus cristatus)

• Species Type: Perennial grasses in low to moderate fertility soils.
• Distinguishing Features: Leaf blades arise at 90-degree angles; emerald green appearance.

8. Danthonia spp.

• Species Type: Native, reclassified from old genus to Rytidosperma.
• Habitat: Dry land environments, steep hill country.

9. Fine Fescue (Festuca rubra)

• Species Types: Chewing's fescue and red fescue.
• Uses: Turf and amenity areas; troublesome weed in hill country.

10. Kentucky Bluegrass (Poa pratensis)

• Species Type: Perennial, spreads by rhizomes.
• Habitat: Low to medium fertility soils, permanent pastures.

11. Kaikouyu (Cynodon transvaalensis)

• Species Type: C4 tropical grass.
• Adaptation: Good growth in warm conditions, excellent water use efficiency.

12. Pasbium (Paspalum dilatatum)

• Species Type: C4 grass; high water use efficiency.
• Challenges: Sensitive to frost and deteriorates in late summer.

13. Ripgut Brome (Bromus diandrus)

• Species Type: Annual grass; problematic in dry areas.
• Seed Dispersal: Sticky, prickly horns cling to livestock.

14. Rough Stock Meadow Grass (Poa trivialis)

• Species Type: Perennial with stolons.
• Characteristics: Similar to other Poa species in appearance.

15. Soft Brome (Bromus mollis)

• Species Type: Annual grass, distinct for hairiness.
• Challenges: Problematic in dry, East Coast areas.

16. Yorkshire Fog (Holcus lanatus)

• Species Type: Perennial grass; very hairy.
• Indicators: Prefers wet, acidic soil conditions (pH ~5–5.8).

Native Tussock Grasses

1. Narrow Leaf Snow Tussock (Chionochloa rigida)

• Habitat: High altitude regions, low palatability.

2. Red Tussock (Chionochloa rubra)

• Habitat: Wetter, swampy conditions.

3. Silver Tussock (Poa cita)

• Characteristics: Shorter, more dispersed than snow tussocks.

4. Hard Tussock (Festuca novaezelandiae)

• Habitat: Lower fertility soils, coarser texture.

Key Takeaways

• Identification of grass species can inform pasture management and suitability.
• Grass species indicate environmental conditions and soil fertility.
• Further studies and readings recommended: New Zealand Pasture and Crop Science textbook, Pasture and Forage Plants for New Zealand.