The leaf blade is patterned with veins. The leaves of most woody plants have one principal vein with several branching veins extending to the leaf margin. Some perennial plants, usually those with palmately lobed leaves, have palmate venation with several veins of like thickness radiating from the end of the rachis (e.g. gooseberry).
A good identifying feature of some shrubs is their arcuate venation (cornelian cherry, dogwood, common buckthorn), where the secondary veins run parallel to the leaf margin towards the tip of the leaf. Leaf apices likewise differ in shape; they may be acuminate or acute (with long, slender, or short points), rounded, truncate (blunt) or emarginate (cleft). Leaf bases may be rounded (European green alder, wayfaring tree), cuneate, i.e. wedge- shaped, (barberry, mezercon) or cordate (hazel).
Leaves may be either simple, with a single blade, which may be lobed, e.g. the hazel, gooseberry and hawthorn, or compound, with three or more blades attached to one stalk, e.g. the bladdernut and common elder.
Simple leaves have blades of various shapes and are described accordingly as acicular, lanceolate, ovate, obovate, orbicular, cordate, rhomboid, etc. Compound leaves may be trifoliate, palmately compound, odd-pinnate or even-pinnate. Trifoliate has three leaflets radiating from the end of the rachis, e.g. the laburnum and common broom. Palmately compound has more than three leaflets radiating from the end of the rachis, e.g.
Thus, for instance, the leaves of Comes mas, Euonymus europaeus, Rhus typhina and Berberis thunbergi turn purplish-red, those of Forsythia suspensa dark violet, Viburnum opulus scarlet, Amelanchier oxalis orange, Rhamnus frangula and Corylus avellana yellow, etc. These autumn hues make just as lovely a picture in parks and in the wild as do the pastel tints of flowering shrubs in spring. Later a corky layer forms between the stalk and the twig, severing the vascular bundles nourishing the leaf.
These are microscopic openings in the epidermis of the leaf, located, as a rule, on the underside. They can be expanded or contracted to control the evaporation of water, depending on whether there is an overabundance or lack of this vital substance. Water is transported to the leaves via a vein-like system of vascular bundles that pass through the leaf stalk and branch in the leaf.
A good identifying feature of some shrubs is their arcuate venation (cornelian cherry, dogwood, common buckthorn), where the secondary veins run parallel to the leaf margin towards the tip of the leaf. Leaf apices likewise differ in shape; they may be acuminate or acute (with long, slender, or short points), rounded, truncate (blunt) or emarginate (cleft). Leaf bases may be rounded (European green alder, wayfaring tree), cuneate, i.e. wedge- shaped, (barberry, mezercon) or cordate (hazel).
Leaves may be either simple, with a single blade, which may be lobed, e.g. the hazel, gooseberry and hawthorn, or compound, with three or more blades attached to one stalk, e.g. the bladdernut and common elder.
Simple leaves have blades of various shapes and are described accordingly as acicular, lanceolate, ovate, obovate, orbicular, cordate, rhomboid, etc. Compound leaves may be trifoliate, palmately compound, odd-pinnate or even-pinnate. Trifoliate has three leaflets radiating from the end of the rachis, e.g. the laburnum and common broom. Palmately compound has more than three leaflets radiating from the end of the rachis, e.g.
Thus, for instance, the leaves of Comes mas, Euonymus europaeus, Rhus typhina and Berberis thunbergi turn purplish-red, those of Forsythia suspensa dark violet, Viburnum opulus scarlet, Amelanchier oxalis orange, Rhamnus frangula and Corylus avellana yellow, etc. These autumn hues make just as lovely a picture in parks and in the wild as do the pastel tints of flowering shrubs in spring. Later a corky layer forms between the stalk and the twig, severing the vascular bundles nourishing the leaf.
These are microscopic openings in the epidermis of the leaf, located, as a rule, on the underside. They can be expanded or contracted to control the evaporation of water, depending on whether there is an overabundance or lack of this vital substance. Water is transported to the leaves via a vein-like system of vascular bundles that pass through the leaf stalk and branch in the leaf.
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The variety of garden materials present a futher range of garden design in your garden plan, involving color and texture as well as linear design.
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