Milk production from summer chicory and turnips

Milk production from summer chicory and turnips

"Chicory or bulb turnips - which is the better feed for cows?" As for any cropping decision, there's not a single answer. Consideration should be given to a range of factors that influence the value of summer crops to your business.

Both crops support similar milksolids responses.
Chicory and bulb turnips both deliver high-quality feed well suited for lactating dairy cows. Research in the 1990s1 showed similar milksolids (MS) responses to chicory and turnips - grams (g) of MS per kilogram (kg) of dry matter (DM); DM of crop consumed by cows. Summer crop selection is more about when you need high-quality milking feed and less about which crop will support the best milk response.

Feed supply curves differ for chicory and turnips.
Chicory supports multiple grazings of a lesser quantity of feed over a longer period. Crops are rotationally grazed for 100 to 120 days between December and March. Chicory behaves like a high-quality, taprooted pasture, delivering better daily DM growth rates and higher-quality feed than summer pasture. However, when summers are hot and dry, chicory regrowth may not match herd demand.

Turnips deliver a single grazing of bulk high-quality feed over a shorter period. They accumulate most high-quality leaf and bulb DM before late December. Pushed forward as a 'feedbank' into summer, turnip grazing starts in January, lasting between 40 and 60 days as a high-quality feed to supplement poor-quality summer pasture.

More crop ground is required for chicory than for turnips. Referring to figure one below, the 'flatter' DM supply feed wedge of chicory means less mid-summer feed is supplied by chicory compared with the peak mid-summer feed supply from turnips.

Relatively larger areas of chicory are needed to supply the same amount of mid-summer feed as delivered by turnips1. Chicory requires four to five hectares (ha) per 100 cows to supply four to five kgDM/cow on a 21-day rotation2 compared to turnips which only require two to 2.5 ha/100 cows for four to five kgDM/cow for 60 days feed3. When comparing costs to grow either chicory or turnips, include regrassing costs in the final cents per kgDM costs for each crop type. Because chicory requires a large area, it requires greater investment in regrassing than the costs associated with returning relatively smaller turnip areas to pasture.

To achieve 60 days of turnip feed, it is important to consider using two bulb turnip cultivars with differing maturities. For example, Cleancrop Toto summer turnip has a 55 to 90-day maturity, whereas Cleancrop bulb turnip has a later maturity of 80 to 110 days. When planted on the same day, farmers can achieve a larger window where the turnips maintain quality.

Weed species present in crop paddocks.
Limited herbicide options exist to control summer broadleaf weeds and thistles in chicory crops. A greater range of selective herbicide options exists for weed control in turnip than chicory crops, particularly for Cleancrop Toto and Cleancrop bulb turnip. If this year's summer crop paddocks were full of weeds, consider a brassica for this 2020/21 summer crop. Select next summer's chicory paddocks now and plan to plant annual ryegrass in autumn 2021 followed by chicory in spring 2021. You'll have two chances to control weed species before chicory is planted later next year.

Summer chicory and turnips - a new dairy grazing study.
To help further understand the strengths and weaknesses of chicory and turnips, PGG Wrightson Seeds commissioned a large chicory and turnip dairy grazing study during summer 2019/20.

The study has delivered insights and information around the use of chicory or bulb turnips as summer feeds for dairy cows. Carried out on a commercial dairy farm near Huntly, the study collected information about chicory and turnips, and responses by lactating cows to the crops. Data included tonnage of crops consumed per ha, cow body condition score (BCS) and milk responses by cows to the crops. These results are currently being analysed and will be fully available to view in the coming weeks.

1Waugh CD, Clark DA, Harris SL, Thom ER, Copeman PJA, Napper AR (1998) Chicory for milk production. Proceedings of the New Zealand Grasslands Association 60: 33-37
2DairyNZ Chicory management (1-72b)
3DairyNZ Turnips - Growing a high yielding crop (1-62)

Article supplied by PGG Wrightson Seeds