South West

A Lesson In Perennial Pastures

This trial is now complete

Key Messages

  • Investigate constraints and prepare paddocks for perennials at least one year out from planting. Preparation should include soil tests and effective weed management, with at least a double-knock
  • Sowing seed shallow is critical. Using an experienced contractor can be beneficial
  • Sowing above (e.g. double) recommended rates can ensure good outcome from investment, and apply fertiliser down the shoot with the seed to assist slow growing perennials
  • Grazing management is vital for persistence. Ensure the paddock is given suitable recovery periods after grazing
  • Trial Rationale
  • Steps Taken
  • Lessons Learnt
  • Looking Forward

Trial Rationale

The project aimed to demonstrate the establishment and benefits of developing a diverse pasture system with deep-rooted perennial species that can exploit moisture at depth, use any unseasonal rainfall, and provide more out-of-season feed to reduce the need for supplementary feeding.

Steps Taken

The project took place in a shallow valley with gravelly sandy loam soils. Soil testing in January 2014 found that phosphorus levels were very low, and also that the soil’s phosphorus buffering index (PBI) was extremely high. The average PBI from three soil samples was 1588, which suggested that phosphorus would limit production. Soil pH was 5-5.5 in CaCl2.

Work commenced in April 2014 to prepare the paddock.

“We worked up the paddock with a Caltros cultivator in two directions to level the paddock, applied glyphosate after weed germination and rolled the paddock to firm the seedbed,” Kim said.

Kim selected a species mix that would be active in winter and resilient. This included phalaris (Holdfast GT), cocksfoot (Grassly summer active), sub clover (Antas), arrow leaf clover (Zulu) and Lucerne (Sardi 7). All species were planted at 4.5 kg per hectare with an Atkinson drill in June 2014.

“The contractor knew what he was doing and that really helped. Getting the seed as shallow as possible (5-10 mm) but getting enough contact with the soil. It’s an economy to use them given their cost and the cost of the seed.”

Fertiliser was broadcast post germination (Ecogrowth NPK at 150 kg per hectare). Kim found it difficult to justify significant expenditure on fertiliser for such a small grazing enterprise.

Germination was generally good with perennial grasses evident in the drill lines. However, very few lucerne plants were detected in the first year. Growth was slow over the spring and the paddock had one light graze to knock down the volume of annual grasses going into summer. The main pest issue in Year 1 was kangaroo grazing (no point in the paddock is further than 150 metres from native vegetation).

In May 2015 Kim recorded a total ground cover of 66%, which increased to 84% by October 2016. This was attributed to tillering of the perennial grasses and an increase in annual grass cover.

Also in 2015, Kim split the paddock into three small paddocks and included them in a grazing rotation. He applied Australian Mineral Fertiliser Grazing P at 330 kg per hectare. But growth during spring was still “unremarkable”.

In 2016, soil tests revealed that phosphorus levels were still low, so Kim applied Pro P (Hi Tech Ag Solutions) at 150 kg per hectare.

Kim was encouraged by widespread seed-set of phalaris and regrowth from rains in January 2017 and hopes that production will increase with time.

Lessons Learnt

Kim says that farmers shouldn’t rush into planting perennial pastures, but instead should prepare at least one year in advance of seeding. He said it was a mistake to sow perennials without properly controlling weeds and addressing fertility issues. If he could have his time again, he would have spent the first year preparing the paddock to ensure a clean seed-bed with good soil fertility.

“I should have seeded a grass legume mix in the first year with a capital application of phosphorus. Then in 2015 I could have grazed the residue and direct seeded following the application of a knockdown herbicide.

Kim also felt that he wasn’t resting his paddocks for long enough post-grazing.

“A thirty-day recovery period in winter is too short. I’m hoping to take that out to 50-60 days in 2017. I’m also hoping to have some better kangaroo control measures.”

Longer rests in winter are in line with research which suggests that ryegrass should be rested for 42 days or when three leaves have developed per tiller, and phalaris should be rested until four fully expanded leaves have developed on each tiller. Other research suggests 4-5 leaf stage for both phalaris and cocksfoot. Grazing should stop at a height of around 5 cm and avoid damaging the high crown of upright cocksfoot varieties.

Looking Forward

Kim expects the paddock should become more productive with time due to the pulse grazing. But for now he is content with the lessons provided to other farmers about the importance of good preparation and management for perennial pastures.

Manjimup

Project Snapshot

Land Manager
Kim Skoss
Shire:
Manjimup
NRM Region:
South West
Property Size
65 ha
Average Rainfall:
Very High - More than 750mm
Enterprise Mix:
Horticulture with farmland grazing
System Constraints:
High phosphorous buffering capacity, low soil phosphorous, Phosphorous constrained
Partners:
NLP, SWCC
Previous Trial Search Trials Next Trial