While it may feel premature to be thinking about winter feeding in July, the reality is that the clock is ticking for those with potential fodder deficits this winter.
It is vital that a fodder budget be carried out soon on all farms. Even if the yard is positively bursting with silage, the exercise will shine light on how long you can feed for this winter. Remember that two of the last four springs were no-shows – feed reserves must stretch into May for some.
What’s in reserve?
Figure 1 outlines the measurements (length/width/height) needed to calculate tonnage in a silage pit. Take measurements in feet and multiply A x B x C. Divide the final figure by 45. Where the silage is single-chopped, divide by 50 as silage will not be as compacted.
Alternatively, assume that poor-, average- or good-yielding first-cut silage will produce seven, eight or nine tonnes per acre, respectively. With second cut, assume three, four or five tonnes per acre for poor, average or good-yielding crops. It must be stressed that getting the measuring tape out is a far more accurate method for quantifying what’s in the clamp.
Those making bales can use Table 1 to calculate each bale’s equivalent weight as 25% dry matter pit silage. This will depend on the length of the wilting period and the weather at harvest. Bales mowed and cut on the same day in relatively dry conditions will have a dry matter of 25%. A 24-hour wilt will lift this figure to 30%, while a 48-hour wilt in hot sunny weather will produce 40% dry matter bales.
What is required?
Once silage stocks are known, calculate what exactly is needed on a per-head basis each month. Table 2 outlines the amount of silage required for each individual livestock class, monthly. Use the table to calculate your demand for fodder this winter. In terms of feeding period length, allow for a worst-case scenario.
If the budget shows a deficit, weigh up your options.
At this point, it may still be possible to overcome a small deficit by being more aggressive with surplus grass removal. Growth is still relatively good and grazing cattle should be followed with 30 units of N per acre to keep production up. If there are more than 14 days of grazing on the farm get in with the mower. However, resist temptation to let skipped paddocks bulk up too much. Grass will slow down in the coming weeks and we need paddocks pulled out and back into the rotation before this happens.
Beef farmers could consider offloading potential winter store cattle early. Daily margin on weight gain over feed inputs is small when storing cattle. If the plan is to sell these in early 2017 as opposed to going to grass, it may make sense to offload sooner if fodder is tight.
If the deficit cannot be bridged by making more bales, selling off stock, or catch crops we must look beyond the farm walls for a solution. Table 3 illustrates some popular bought-in options for boosting fodder reserves this winter. Note that many alternatives to grass silage must be supplemented with protein (eg maize silage, whole crop, fodder beet) and most will need mineral supplementation. It is also imperative that maximum inclusion rates for these alternative fodder options are adhered to. Apart from out-wintering options, high-quality grass silage represents the simplest and most cost-effective winter forage available.