Notobasis syriaca, the Syrian thistle, is a species in the thistle tribe within the Asteraceae. It is native to the Mediterranean region and the Middle East, from Madeira, the Canary Islands, Morocco and Portugal east to Egypt, Iran and Azerbaijan.
It is an annual plant belonging to the semi-desert flora, growing to 30–100 cm tall. The leaves are spirally arranged on the stems, deeply lobed, grey-green with white veins, and sharp spines on the margins and apex. The flowers are purple, produced in a dense flowerhead (capitulum) 2 cm diameter, surrounded by several spiny basal bracts.
This plant might be poisonous
How to get rid of:
Ensuring proper nitrogen levels will give you an extra edge against clover. It’s a lack of nitrogen that allows clover to thrive, so try a nitrogen-rich weed-and-feed formula. Organic fertilizers might do the trick if you have a small amount of clover, but if your lawn is becoming overrun, choose a standard fertilizer that is not slow release.
Get rid of small clumps as soon as you notice them by gently loosening the soil around the base with a spade or your fingers, then plucking the clover up. Be sure you get all of the root.