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.
Plant evergreen ornamental varieties for year-round specimen plants. Grasses include blue oat grass (Helictotrichon sempervirens) and tall blue fescue (Festuca amethystine). Blue oat grass is a semi-evergreen fountain grass. It grows well in zones 4 through 9 and needs dry, well-drained soil.