Ononis spinosa aka Spiny Restharrow

Ononis spinosa, also known as spiny restharrow or just restharrow, is a flowering plant in the family Fabaceae. It is found throughout much of Europe, including Britain, although it is rarely found as far north as Scotland. This semi-evergreen subshrub or woody-based perennial can reach a height of around 60cm and has an upright habit with stiff, spiny stems. The plant has small, oval to elliptic leaves arranged in groups of three, and in the summer it produces pea-like flowers in shades of pink, purple, and blue that are borne all along the stems. The plant prefers a sunny position in a well-drained neutral to alkaline soil and can also thrive in poor soils, often developing spines in such conditions. It is similar to O. repens but does not spread through rhizomes. The mature roots of Ononis spinosa are very tough, giving it the common name "Rest Harrow" because ploughs and harrows would struggle to break through it in the past. When the plant is bruised, it releases a pleasant scent. Additionally, it forms a symbiotic relationship with certain soil bacteria, which create nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is used by the plant itself, while the rest can be utilized by neighboring plants. Overall, Ononis spinosa is a useful plant. However, if you need to get rid of it, specific methods for removal were not provided in the given descriptions.