While the rain keep coming, it is thankfully bringing mild south westerly wind as well, delaying the expected slow down in growth for late October. Amazingly, the range in growth recorded on farms over the past week is minimal, from 30-34 kgDM/ha/day and was irrespective of location and soil type. So, what growth should we be planning for in November. For the coming week is expected to continue wet and mild again delaying a serious decline in growth. For most of our farms we are budgeting for growth ranging from 25-28kgDM/ha/day for the coming week and reducing weekly to 20, 15, 12, 8 kgDM/ha/day through November.
These predicted November growths are important in the context of the first closed paddocks in October. Above average growth through October now means that the first closed paddocks are growing well with covers ranging from 500-900 depending on when it was closed. So the question arises: What cover will it be at for grazing in early February? Should I graze it again? Considering current cover of 900kgDM/ha, average of 14kgDM/ha/day growth through November and average 4kgDM/ha/day growth through December & January then this paddock should increase cover to 1500 kgDM/ha by the beginning of February. So, should you graze it again. At this point in time, this cover is too advanced – if the expected growths are realised it is not ideal to carry this cover over the Winter. However now is not the time to decide if it is to be grazed again – this decision should be left until the final 10-14 days of the grazing in late November – you will be better placed and better informed then to make the decision.
A common question this week relates to using dry cows to clean out paddocks? In answering this question I am assuming that grass supply is strong and on target – if not then the dry cows should be off the grazing platform. There is the perception that using dry cows to clean off paddocks is bad management. Why? 1. If practised over an extended period of time – body condition can suffer. 2. Residency time in the paddocks is too long seriously affecting the re-growth of the paddock and its ability to grow over Winter. If body condition is monitored and residency time in a paddock is kept to less than 5 grazings – then it is an option. For it to be effective dry cow number must be high so that “the final grazing” is fast. The use of strip wires may also be helpful – but be sure that the current is good especially if the milking cows are nearby.
For those of you with kale, rape or fodder beet crops, it will soon be time to use them, if not already doing so. Do you know what the yield of the crop is? Are you allocating enough dry matter per day and how long will the crop last? Measuring DM yield in these crops takes a similar format to measuring grass DM yield using a quadrant but cut to ground level. It is better however to use a meter square quadrant for this purpose and using the following formula – Weight (grams) x Proportion of DM x 10 to give the yield of DM/ha. Try to measure these crops when it is relatively dry – mainly to stay dry yourself but also to use the standard dry matter percentages of approximately 11% for kale and rape and 13% for fodder beet. Kale crops very considerably across the country. Looking from outside the paddock some crops look very tall (>4-5ft) with good density, prompting the suggestion it looks like a “ten tonne crop”. On examination and measurement of these tall crops the stalks are thin & fine which does not weigh heavy when cut & weighed with inevitably lower DM yield than expected. Don’t be fooled by the height of the crop – get in there and weigh it – this is the ultimate test. On a positive note the Kale varieties which grow tall and thin are likely to have much higher utilisation down to the base – especially if being grazed by this years calves – as opposed to a lower growing crop with very thick stalks – these are better utilised by older animals.
