Shoulder Shrug Muscles. The shoulder shrug is a simple exercise to perform, and as the name suggests, it does work your shoulder muscles -- namely, the trapezius, or upper shoulder. Additionally, the shoulder shrug works muscles of your back -- the levator scapulae and erector spinae.
Oxalis makes a perennial ground cover in shady areas. Oxalis (Oxalis spp.), also called sorrel or shamrock, has a negative image if all you know of them are weedy, invasive cosmopolitan species. However, most of the about 800 species of oxalis are native plants in tropical South America and Africa or in temperate areas of the Old and New World. Many are used for landscaping or as houseplants. Oxalis are perennial plants but can give the appearance of annuals by going dormant in winter or during droughts.
A: The weed you have is in the family oxalis, which if placed in a pot is often called shamrock. The flowers may be white, purple or yellow. The petals often resemble clover which causes people to confuse this plant with a common variety of clover.: The weed you have is in the family oxalis, which if placed in a pot is often called shamrock. The flowers may be white, purple or yellow. The petals often resemble clover which causes people to confuse this plant with a common variety of clover.