Related Terms. 1  operating system virtualization. 2  mobile operating system (OS). 3  OS-operating system. 4  server operating system. 5  system. 6  Microsoft Windows XP operating system. 7  Linux OS (Operating System). 8  paravirtualized operating system. 9  NOS-network operating system. 10  Chrome OS.
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.
Abies. Forming perfect pyramids, firs bring a bit of mountain magnificence to urban and suburban gardens. This family of long-lived evergreen trees is valued for soft needles, graceful branches, and strong fragrance.It's no wonder that fir cultivars are frequently chosen by the American Conifer Society as Conifer of the Year. Balsam, Fraser, and noble firs are popular Christmas trees.ompact blue alpine fir. Abies lasiocarpa var arizonica 'Glauca Compacta' offers silvery blue needles on a small tree that reaches 15 feet tall and 10 feet wide. Zones 5-6. Abies concolor 'Compacta' is a slow-growing selection with blue-green needles and reaches about 10 feet tall and 6 feet wide.