African lovegrass a drought saver

Over spring, summer and autumn steers gained on average close to 1.0 kg/beast/day with per hectare gains ranging from just under 2.0 to nearly 4.0 kg/day depending on aspects like added nitrogen and stocking rate manipulation. Depending on supplementation strategy, good performances were also achieved from winter grazing. These results were published in the proceedings of the 10th annual conference of the NSW Grassland Society.

That's not to suggest African lovegrass is a "lovable weed", but the reality is that it infests hundreds of thousands of hectares, and for many, it is impossible to eradicate. No one suggests encouragement of the weed, but if you have it and it is impossible to eradicate, it is sound logic to endeavour to manage for best animal productivity.

Our property is an example of how to live with it, at least until we can eradicate it from a given area. And because we adjoin a roadway that will in all probability always be a constant source of reinvasion, it is sensible for us to learn how to best manage it.

African lovegrass especially favours light/medium textured soils. It is an issue in tableland, coastal and slopes areas. Within a mixed species pasture (for example where it has invaded) it tends to be one of the least palatable grass species, although native wire grass (Aristida ramosa) tends to be even less palatable. Because of lower palatability, it tends to be un-grazed if ample softer feed is available, and hence quickly becomes more rank and even less palatable. It is long lasting and can tolerate heavy grazing.

Quality of most grasses, including African lovegrass, is closely related to soil fertility, as well as plant growth stage. If it is new regrowth on fertile soil, quality can be excellent and good weight gains, like as occurred in the Tenterfield research, can be excellent. High soil fertility depends on several aspects such as correcting soil deficiencies like phosphorus and sulphur, and having a suitable legume as part of the pasture. Adding nitrogen fertiliser can substitute for lack of legumes.

We had planned to convert one of our African lovegrass infested paddocks to winter fodder crop this autumn with fallow summer spraying to remove all vegetation, including African lovegrass. However, because the paddock, especially the lovegrass, was proving good quantities of feed, despite drought conditions, we have retained it for the time being and switched the winter fodder crop to another non-infested paddock.

Normally we crop an infested paddock for three years with regular summer glyphosate treatments (after each rain event) to eliminate all adult weed plants and endeavour to exhaust weed seed reserves. After the third winter fodder crop, with the last one removed around early September, we sow down to a tropical grass pasture (in November). Well established tropical grass pastures help prevent reinvasion via adjoining public road African lovegrass.

This program has worked well. One of our tropical grass paddocks is around 17 years old and although a few weed plants have been able to establish within it, it still has many years ahead before we would regard this as a problem.

With paddock feed relatively scarce over the last three drought years African lovegrass on fertile paddocks has not been a problem for grazing management. While sometimes after a reasonable rain the weed may get away somewhat, there is generally fresh growth at the plant butt and this is grazed off in conjunction with lower quality advanced parts of the plant.

If African lovegrass plants "get away" in response to a good rain event, or if going into winter with good levels of dried off or frosted material, producers, including ourselves, can maintain good animal performance via supplementing with a good protein source, including dry licks with urea. In a way, African lovegrass has provided a sort of "hay stack" for good utilisation over the past/current drought.

Next week: Soil tests vital for crop and pasture decisions.