This is a re-post of my article from about one year ago.
Look around on road sides or bare disturbed ground and you are likely to see the small yellow flowers of Bur Buttercup (Ranunculus testiculatus). It is also known as Hornseed Buttercup or Horned-Head Buttercup. It is native to southeastern Europe (Balkan Peninsula). It was first recorded in North America from Utah in 1932. The first record for British Columbia, in southern regions, was in 1966 and it has spread widely since then.
It is an annual that flowers early in spring. Although it does not compete well with healthy grass, it can quickly occupy disturbed areas, our native grasslands included. It is toxic to livestock, especially sheep. It thrives particularly well on bare soil in campgrounds and seeds are easily dispersed on camping gear and vehicles. Control is by mechanical removal or herbicides.
Bur Buttercup is not listed on the regulated or unregulated invasive plants in BC. You can see a list of invasive BC plant species here.
Two more pictures taken by Rick Howie in 2017. This “stand” of Bur Buttercups is on East Shuswap Road.