Basal leaves are on stalks, upper leaves clasp the stem.
Leaf shape, seeds, and flowers have some resemblance to dandelion. Annual sowthistle is in the same family as lettuce, and is resistant to all lettuce herbicides. Often the worst weed in lettuce, sowthistle s similar growth habit means that it germinates at the same time, has a similar growth rate, and can compete directly with lettuce to reduce yields. By seeds, which can be windborne, as in the sowthistle s famous relative, dandelion. A very prolific producer of seed that can produce a dense population of seedlings that are difficult to remove by hoeing or cultivation.