Goats as targeted grazers for blackberry control

Goats are historically used for brush control, but a recent Oregon State University study by Ph.D. candidate Claudia Ingham looked specifically at the effectiveness of high intensity-short duration goat browsing for the control of Himalayan blackberry and English ivy.

Blackberry control is a common issue for many ranches in both Mendocino and Lake Counties and so I thought it would be interesting to hear about Claudia’s research and results. She compared the effects of goat browsing on blackberry vigor by quantifying the densities of different age class stems, comparing it to mowing alone, and goat browsing followed by mowing over a three-year period.

Her results showed that total stem density declined, but the primocane density actually increased after all three treatments, which means that the blackberry population was still vigorous. All three treatments, however, resulted in a decline in blackberry cover and a favorable increase in both perennial grass and forb cover.

She could not detect any significant differences between the three treatments, which mean that goat grazing alone controlled the blackberries as well as mowing or grazing plus mowing. Given the fossil fuel costs of mowing, goats as targeted grazers are a better option.