In this 5 minute radio interview, Dr Katherine Tozer from AgResearch explains why they’ve been very busy growing weeds for an experiment, and what they hope to achieve. Will the intervention of the right goats at the right time, in the right conditions, reduce the need for chemical sprays?
Here is an excerpt from an article about managing thistles by the BHU Future Farming Centre:
“Sheep and cattle generally avoid grazing Californian thistle unless pushed hard or when the plants young and tender. Goats however will graze Californian thistle move avidly than sheep and cattle so they can be used as part of a Californian thistle management strategy, and they clearly have the edge over mowing in steeper terrain. However, goats, like other means of defoliation are no silver bullet, and they need the correct management to get the best weed control effect. For example, if there are other more palatable fodder species available, goats will graze those in preference. Goats won’t clear Californian thistle overnight, as the control mechanism is the same as mowing, i.e. exhausting the underground reserves, so it will take several years to eliminate Californian thistle under intensive grazing pressure, and longer under more infrequent / lower pressure.
Goats will also graze other thistles and are quite partial to the flower heads, but, it is important to manage grazing so that thistles don’t go to seed as the seed will pass right through animals guts and therefore be spread in the manure. This especially important for annual and biennial thistles as for these species, the seed, not the root, is the fundamental stage of the lifecycle and only means of reproduction and spread.
Milking goats are not suitable, due to disease and parasite problems, and only meat goats are up to the task. However, the final plus for goats, is unlike mowing and subsoiling, if well managed, they will produce an income, rather than just burning diesel.”