Rhamnus cathartica (Common buckthorn): Ecology
	Habitat: In the British Isles, the common buckthorn is a common hedge or woodland shrub found on chalk soils. It will adjust to any soil, even growing on very wet sites, and will tolerate full sun or semi-shade. It is hardy in the US from zone 2 to 7, and has naturalized in Iowa, now often found in vacant lots, along fencerows, and in open woods. Diseases: This species is the alternate host of Puccinia coronata, an organism causing oat leaf rust. It is susceptible to leaf spot, rust, powdery mildew, aphids and 3 types of scale-black, gloomy and ivy scale.	Distribution:The common buckthorn is native to Europe and western and northern Asia. It was introduced for hedge plantings, later escaping and becoming naturalized across much of Iowa, where it is considered a primary noxious weed. There are three native buckthorns in eastern North America: the Carolina buckthorn (R. caroliniana), the lance-leafed buckthorn (R. lanceolata), and the alder-leafed buckthorn (R. alnifolia). The European buckthorn (R. frangula) and the common buckthorn (R. cathartica) are, however, becoming the most common species.