Evidence of slowing yield growth – the example of Swiss cereal yields

We analyze trends in yield growth and yield variability of barley, maize, oats, rye triticale and wheat in Switzerland from 1961 to 2006. In contrast to linear trends in cereal yield growth that are usually assumed for Europe, cereal yields have leveled off due to widespread extensive cereal production in Switzerland since the early 1990’s. This might also indicate prospects for future crop yield developments in other countries if similar farming practices are widely-used. Even though we find increasing yield variability for barley and rye, no increasing trend in relative yield variability (relative to yield levels) is found for all analyzed crops. Furthermore, this study emphasizes the importance of robust regression methods to ensure reliable results in trend estimation.