Silphium and drought tolerance
Land Institute scientist David Van Tassel had spent several years working with the maximilian sunflower, trying to develop yet another candidate for the field of mixed perennials that is the organization’s long-term goal.
The idea is that a field of mixed perennials — the technical term is “perennial polyculture” — would mirror the natural prairie, which has existed for centuries without artificial fertilizer or irrigation, holds the soil in place and is generally resistant to pests and diseases.
In the drought years of 2011 and 2012, however, Van Tassel and others noticed that a distant cousin of sunflowers known as silphium showed little sign of being bothered by the dry conditions, while many of the other crops they were working with turned brown and stopped growing.
“Silphium started as a side project, and for the first few years, I didn’t keep really specific records,” Van Tassel said. “After what we saw in 2011 and 2012, I started taking silphium more seriously than the maximilian sunflower.”