Clever grazing can make all the difference

These include naturalised clovers, improved clovers and other legumes, and annual grasses such as ryegrass and bromes.

A lot of this feed remains good quality as it dries off if late spring summer conditions remain relatively dry.

My late father used to say summer rain only spoils the dry winter/spring carryover feed. 

While that statement remains sound to this day, the reality is that for almost all of NSW, even the extreme southern areas, summer rains, while erratic, are part of our environment.

Nowhere in the state are we a true Mediterranean environment (hot dry summers cold wet winters). Clearly the challenge is to effectively use summer rain by summer growing pastures, even in pastures with good winter annuals. 

If we can grow persistent summer-growing perennials with winter annuals we have a logical pasture system.

If summer conditions are dry, quality of dry winter/spring carryover feed can remain good for most of the summer.

If summer provides good rains, green growth from summer species can more than compensate for the deteriorating quality of the dry winter/spring feed.

Native or introduced perennial grasses, such as tropical species like Premier digit grass can coexist well with good winter pastures.

But grazing management that recognises compatibility issues can improve performance from both winter and summer sections of the pasture. 

Too much winter spring herbage (around four tonnes to the hectare or more herbage, drymatter basis), as it dries out can totally shade out summer species such as native grasses and tropical grasses.

If plants can’t see sunlight they fail to refire.

Native perennial grasses seem more sensitive to shading out than introduced tropical grasses.

Winter spring herbage also rapidly uses soil moisture and despite the wet winter-early spring can largely dry-down the soil moisture profile.

So summer growing species commonly face both shading and a dry profile until a good rain event occurs.

4.0 t/ha is still a lot of herbage which means tropical or native grass pastures don’t need to be grazed into the ground coming into and through to summer.

A good policy is to get a feel for what 3.0 – 4.0 t/ha looks like and where possible, especially best summer paddocks, graze accordingly.

In our case this past spring it was not possible to graze all paddocks to 4.0 t/ha drymatter, despite increasing stock numbers.

Cutting a tropical grass paddock (the legume component) for hay helped put more grazing pressure on other paddocks. 

The reverse can happen if the summer is wet and summer herbage gets more or less out of control with paddocks having in excess of 4.0 t/ha summer grasses.

If these are not grazed down reasonably by autumn germination of winter clovers and other legumes can be adversely affected.

If such a season eventuates summer grasses on fertile paddocks make good hay or silage if cut before the end of flowering.

Having too much feed is a great problem and provides opportunities for hay/silage, take on adjustment, contributes to soil organic matter, and an opportunity to close dual-purpose crops early to maximise grain recovery.

Grazing pressure on at least some paddocks to minimise carryover drymatter levels is just one part of the best management strategy.  

Next week. Long term crop study confirms essentialness of fertiliser and rotations.