Leafy spurge, a tenacious weed introduced from Eurasia in the mid-1800s, is aided in its propagation by mourning doves who ingest seed and deposit it in the form of waste. Left to their own creeping, leafy spurge plants can expand about 15 feet per year. With the aid of birds, however, its territory burgeons at a much faster rate.
Leafy spurge has no natural enemies in North America.
All photos by Chad Cheyney. With a taproot that extends more than 20 feet in depth, a shallow, horizontal root system that creeps steadily, plus aerial distribution by birds, leafy spurge has become a major concern and economic threat in most regions of Idaho. It has created significant economic losses in the Dakotas, Wyoming, and Montana, and threatens to do the same in Idaho. Unfortunately, the weed has no natural enemies in North America. A relatively new biological immigrant from Europe, however, appears to be highly successful in stifling the weed's progress and reducing it to a manageable level.