Japanese barberry (Berberis thunbergii), Frederick Law Olmsted National Historic Park, 2015.

This barberry, native to Japan and eastern Asia, may be known as Japanese barberry, Thunberg's barberry or red barberry. Don't confuse it with American barberry (B. canadensis) or other Barberis species; Japanese barberry grows flowers in umbrels (i.e., short flower stalks spreading from a common point like an umbrella), not racemes (i.e., unbranched flowers). Though beautiful, it is now recognized as an invasive species in many parts of the US; it is avoided by deer and often replaces native species, it raises the soil pH, affects soil nitrogen levels and is even a favoriable environment for ticks due to the high humidity present in barberry's dense foliage.