MANAGING PASTURE IN THE WET
Look after lucerne and it will return the compliment
THERE are quite a few real stories flowing through about the two extremes of pasture survival during the drought time.
For those of us who have had significant rain in the past two months, it may be either a case of amazement of large amounts of pasture regeneration, or it is shock at still seeing large areas of bare soil. This can be on a paddock to paddock basis.
Lucerne, as we all know, has some of the toughest survival attributes of all pasture species.
This huge tap root system, given time to develop, can provide large reserves of moisture and nutrient to the above ground part during dry periods.
So two days after rain starts and you observe emerging green shoots among those brown stalks from old tussocky lucerne crowns, you know that you will soon have some high protein pick initially for your livestock.
For those of us who have been lucky enough to have a significant rain event of some five inches plus, you may now have a flourishing paddock of lucerne.
However, be cautious of this early excessive growth as its higher tannin levels may exacerbate the bloat problem, particularly for introduced hungry cattle.
The other caution clause is that lucerne needs a spell to regenerate its crown and some say the root system also, with carbohydrates, the focal point of lucerne production and hardiness.
This spelling period, to allow the plant to flower and produce some seed, is invariably performed at roughly this time of the year. It allows the plant to persist and perform for a longer life span in years and gives it strength to survive insects or soil diseases.
This persistence also may come down to having good establishment conditions with soil structure, low levels of aluminium in acid soils, medium salinity issues and variety choice being key features. All these parameters point to having a much better branched root system with a large diameter penetrating tap root.
Variety choice is a challenge and you need to conduct your own in field trials with your own needs and challenges of your soil topography and limitations.
Start by looking at crown height. This has great inputs into persistence and timing of production flushes.
I get plenty of arguments about this, however the lower the crown in the soil surface, the longer the persistence, even though it probably initially produces less dry matter per year than a highly winter active variety. You must also protect these exposed crowns from tractors, hoof prints and wetter conditions.
Any lucerne stand subject to anaerobic (oxygen-free) conditions, does not like it at all.
Drowning under water in low spots is fairly immediate for lucerne to die out, however even wet conditions can start the demise of your lucerne stand, no matter if it is pastures in Cloncurry or the black soil flats of the Kinbombi creek.
I recall a small corner of our family lucerne farm having water from an irrigation event, lie there for less than 12 hours before I was delegated to dig a draining trench in this heavier soil type.
No matter how we looked after that section, paspalum took over in this decaying lucerne stand.
So look after your lucerne stands, as they will look after you in these usual challenging times.
You must also protect these exposed crowns from tractors, hoof prints and wetter conditions.