Time to check pasture fertility

Published on: 19:31PM Sep 09, 2010

Time to check soil conditions and fertility

   Without testing your soil, it is impossible to know how much fertilizer you will need to apply to your pastures and fields this fall.  If your not careful, you may over apply amendments and that’ll put an extra punch in your pocket!  Not to mention also potentially damaging the environment.  However, not applying enough amendments will mean a shortage of vital nutrients.

   A soil test, which is minimal in cost if you work with your local FSA office.  And in most cases the FSA office will pay for if you stress the importance of not over applying, seeing as how that could be "detrimental to the environment".  The staff at the FSA can help you decide which nutrients are required allowing a more targeted approach to fertilizer use, saving you both time and money.  Something all of us have little to no amount of.

   Improving soil fertility will also improve late season growth, increase perennial ryegrass and white clover content, decrease weed competition and increase nutrient uptake prior to winter hibernation.  What more could you want from your forages?

   This time of year, avoid prolonged periods of very heavy grazing.  Instead use short four to five week rest periods, ideally encouraging clover & alfalfa recovery prior to that first killing frost of the fall/winter.  White clover is a perennial legume. The key to its survival and production is its multi-branded creeping stem called a stolon, which provides sites for new leaves, roots and flowers.   White clover fixes nitrogen into the ground - converting it to nitrates.   Livestock are likely to consumer 20 -30 per cent more white clover than grass (especially pig’s), assuming equal access - which leads to increased live weight gains.

   White clover will increase the crude protein content of first cut haylage by one per cent for every 10 per cent increase in the amount of clover in the sward.   The root system of white clover and sunken crown alfalfa can also help tackle soil compaction, allowing freer movement of nutrients and water.   The optimum amount of clover in a field is 30% of the total dry matter.  At this level, clover can fix 150kg N per acre into your pasture soils per year!  To reach 30 per cent clover growing, the sward needs to look more like there is 50-60 per cent clover at its peak growth in August & September.

   Ideally grass/clover should follow cereals, roots or brassicas, as these will have reduced nitrogen levels in the soil which in turn encourages clover establishment.   In mixed swards, seed rates should be 2-4 kg per ha (150 clover seedlings per metre squared), with broadcasting or "frost seeding" in February or March being a more reliable method than drilling in the late summer or early fall.  The best time to "Frost seed" clover is early in the morning when the ground has heaved or "honeycombed", so when the sun hopefully warm’s the top few inches of the heaved soil it will close over the seed ensuring a good seed to soil contact.