Successful forage crops don’t happen by chance, it is the decisions made pre and post establishment that determine the outcome. This was one of the messages from a recent B+LNZ field day in Tasman.
This was one of the take-home messages from a recent Beef + Lamb New Zealand field day in Tasman.
Speakers at the ‘Setting your crops up for success’ day included Chris Sanders and Stu Hunter from PGG Wrightson Seeds who talked about crop establishment and the importance of understanding why a paddock ear-marked for renewal was no longer performing.
Low fertility and soil pH, weed pressure, soil compaction or pugging damage and pasture species reaching the end of their productive life are all valid reasons for poor performance and the crop phase is an ideal opportunity to address these issues before returning the paddock to pasture.
They said soil testing was one of the most cost-effective investments farmers can make before crop establishment as it helps identify nutrient deficiencies and lime requirements.
Correcting these early will improve crop performance and set future pastures up for success.
Weed control
The crop phase is often the cheapest and most effective time to tackle difficult weed problems before they become an issue in the subsequent pastures.
Before drilling, Chris and Stu recommended identifying the problem weeds in each paddock and drawing up herbicide programmes tailored for individual paddocks.
A double-spray programme will improve weed control and reduce future weed pressure.
Before spraying, ensure plants have sufficient leaf area to effectively absorb herbicides – but enough time should be allowed between spraying and drilling.
Conserving moisture
Early spraying then leaving paddocks in fallow can help build soil moisture before drilling, improve seedbed conditions and support stronger crop establishment, particularly through dry summers.
Temperature matters
Be patient and wait until soil temperatures are high enough before drilling.
Ideally, soil temperature should be consistently close to 12 degrees before sowing brassicas.
Warmer soils will result in faster emergence, better early growth, the seedlings will be better able to compete with weeds and won’t be so vulnerable to pests.
Seed depth
Seed placement is important. Brassicas should be sown at a depth of 10-15mm while small seeded species such as clovers, chicory and lucerne should be drilled at a depth of 10mm.
A well-prepared, level seedbed and good seed-to-soil contact are all important for successful crop establishment.
Rolling could be considered where appropriate.
Monitoring pests
Slugs, Nysius, Springtails and Grassy can decimate crops so regular monitoring from crop establishment is important.
It is easier and cheaper to deal with small issues early rather than risk crop failure.
Direct-drilled systems are the most at-risk, so proactive management and regular crop walks are essential.
Forage crops and parasite management
Stu Hunter shared the results of PGG Wrightson Seeds research which found crops typically have a lower parasite challenge than traditional pastoral systems while also driving lamb growth rates.
Wormwise vet and farmer Mary Bowron reminded attendees that forage crops were not a silver bullet and good management and monitoring was still essential.
Potential parasite sources with crops include grass contamination, grassy paddock edges, previous grazing history and poor crop maintenance.
She told the audience that quarantine drenching was essential particularly for farmers buying in store lambs as they wanted to prevent resistant parasite populations coming onto the farm.
This meant using an effective quarantine drench as triple drenches alone may no longer be sufficient if there is resistance) and be careful where the lambs were grazed immediately after drenching.
Once animals are on forage crops, they will be better able cope with any parasite challenges because they are being well fed.
This reinforces the importance of good parasite management and good quality nutrition working together.