Time for the topper and the sprayer
Pasture quality has fallen faster than normal this year as a result of poaching and undergrazing in May, followed by the warm dry conditions in early June, writes Tommy Kelly, Teagasc Advisor, Belmullet. Grazing paddocks need remedial action to get them back into shape for the remainder of the year. In the less intensive farming areas it is noticeable that there is a good deal of under-stocking. The high store cattle prices in spring could have led to some farmers purchasing fewer stock. The extra grass will go to waste unless it is harvested and, while there is not much of a margin in making baled silage or hay for sale, there may be some return to it this year when silage stocks are low. On the other hand, some of the more highly stocked dry-stock and dairy farms are running short of grass. These could be a market for silage later in the year. Another alternative would be to sell the crop as a standing meadow which would mean no expense in harvesting, and any revenue gained would be a bonus.
Even where grazing management is good, there are few pastures that will not benefit from topping at this time of the year. The removal of seed-bearing stems and tall grass will encourage new tillering and set up swards for better quality into the autumn. If grass is scarce the less productive stock can be made do the ‘topping’. For example, suckler cows in good condition can be forced to clean off pastures after the finishing cattle. This will not affect their performance if the restriction is only for a few days. Topping reduces growth rates so if grass is scarce only top after paddocks are well grazed and do not do too much of the area at any one time.
An added advantage of topping is that it removes weeds like thistles and nettles. Thistles are controlled by two toppings per year. The first topping should be done before the thistles flower but this does not catch all the smaller plants coming off the creeping root system. The thistle re-growth after topping is fairly weak and if removed again it will weaken root reserves and give satisfactory control. Nettles grow in clumps on loose fertile soil. Cutting before flowering gives adequate control. Topping also gives some control of docks if repeated regularly. In silage crops, docks are allowed build up good root reserves through a long growth period and topping later in the year is of little use as a control measure.
Weeds should be sprayed before flowering and while growing actively. Thistles are controlled with MCPA products when applied in warm weather at a rate of five litres per ha. Spot treatment with brushwood type herbicides (products containing triclopyr) is the most appropriate way to control nettles. Docks are the most troublesome weed of intensive grassland and are almost impossible to eliminate in ground continuously being used for silage. We have to be satisfied with containment and aim to keep docks at a level where they do not seriously affect silage yield and digestibility. Where silage and grazing fields can be rotated annually there will be better control than with continuous silage. However, silage areas are often fixed and in these cases control by herbicides is the only practical method. Docks could now be treated in the silage aftermath. Spray when the plants are growing vigorously and when leaves have reached at least 10 cm (4”) in length.
No one product will eliminate docks completely; some require two treatments or a main treatment followed by spot spraying. Dicamba-based herbicides in combination with products like triclopyr, CMPP and 24D give medium to long term control. Doxstar, which is a mixture of triclopyr and fluroxpyr, also gives good long-term control. All the above products kill clover. Asulox and Prospect can be used where clover is present and while these do not kill clover they do weaken it. Dock seeds remain in soil for 50 to 60 years so any time soil is disturbed and the seeds are exposed some will germinate and produce new plants.
Ragwort, thistle and dock are among the weeds scheduled under the Noxious Weeds Act 1936.
People responsible for land on which these weeds are growing are liable to prosecution. Also under the cross compliance measures of Single Farm Scheme, farmers are required to minimise the spread of these weeds and may be penalised in their payments for failing to do so.