When analysing normally distributed data, standard deviation can be used in conjunction with the mean in order to calculate data intervals. If = mean, S = standard deviation and x = a value in the data set, then. 1  about 68% of the data lie in the interval: . 2  about 95% of the data lie in the interval: + 2S.
Little gem arborvitae (Thuja occidentals 'Little Gem') is an evergreen shrub that keeps its brilliant color and foliage all year long. Growing 1 to 3 feet tall, little gem has medium texture and a slow growth rate. The dense dwarf shrub has a compact form and globose shape.
Most popular of the evergreen azaleas are the Kurume hybrids. They are popular for forcing in pots and for planting outdoors. In the southern United States, they become large, showy shrubs in the spring. They are fairly slow-growing plants with dense, twiggy growth.