Abiotic factors

Nonliving factors such as nutrient deficiencies and water or temperature stress


Process by which substances, particularly water and minerals, are moved into the plant. This occurs mainly through the roots in the tip region where root hairs are present, but it may also occur through leaf surfaces.


Focal point, something that deliberately stands out from the overall landscape


Attachment of dissolved or gaseous pollutants to the surface of solids. For example, odors from freezers and refrigerators are adsorbed to baking soda.

Adventitious buds

Buds arising at sites other than in the terminal or axillary position

Aggregate fruits

Fruits that come from a single flower with many ovaries


Leaf arrangement where leaves are arranged in alternate steps along the stem with only one leaf at each node.


An insect that undergoes slight or no metamorphosis


Flowering plants that produce seeds enclosed in a fruit


Plants that pass through their entire life cycle from seed germination to seed production in one growing season, then die

Anvil style shears

Pruning shears with a sharpened blade that cuts against a broad, flat plate


Geologic formation that holds and yields usable amounts of water. The water in an aquifer is called groundwater. Aquifers may be categorized into confined aquifers and unconfined aquifers.

Atmospheric humidity

Amount of water vapor in the air, expressed as a percentage of the moisture saturation of air


Ability of plants to manufacture their own food

Axillary buds

Buds arising in the leaf axils


Design principle that refers to an aesthetically pleasing integration of elements; a sense of one part being of equal visual weight or mass to another

Bare root plants

Perennials that are dug up during their dormant season and sold without soil around the roots


A nontechnical term that refers to all the tissues outside the vascular cambium, including the periderm

bedding plants

Encompass a wide variety of non-hardy, seasonal things like annuals, tropicals, herbs, vegetable transplants, etc.


A fine-bladed, warm-season grass with exceptional drought tolerance that aggressively creeps by both rhizomes and stolons.


Plants that start from seeds and produce vegetative structures and food storage organs the first season and flowers, fruit, and seeds the second season

Binomial nomenclature

System of naming organisms in which the name is composed of two terms


The variety of genes, species and ecosystems in the aggregate, across the larger landscape.

Biological control

Using living organisms (i.e., natural enemies) to reduce pest populations (typically insects and weeds)


Living agents such as fungi, nematodes, bacteria, and viruses


Expanded, thin structure on either side of the midrib of a leaf. The blade is usually the largest and most conspicuous part of a leaf.


flower prematurely


Modified leaf or scale with a flower or flower cluster in its axil. Often brightly colored, as in poinsettias.


A stem that is more than one year old and typically has lateral stems

Branch bark ridge

Prominent ridge of raised bark that forms within the branch crotch

Branch collar

The swollen area that forms around the base of a branch, often appearing a bit swollen

Broadleaf evergreens

Angiosperms trees that retain foliage throughout the year


Small package of partially preformed tissue which becomes leaves/stems or flowers


The union of one bud and a small piece of bark from the scion with a rootstock


Shortened, compressed, underground stems surrounded by fleshy scales (leaves) that envelop a central bud located at the tip of the stem

Bypass pruners

Pruning shears with two blades that cut like scissors

C3 plants

Found in temperate to cold climates with high moisture environments and represent the majority of plant species. They typically are slower-growing plants than C4 plants and use CO2 less efficiently as a result of an energy-wasting process called photorespiration.

C4 plants

Found in hot, dry, subtropical to tropical environments. They are fast growers and have higher rates of photosynthesis than C3 plants. Because C4 plants do not photorespire, they are more efficient in fixing CO2 than C3 plants.


The sepals of a flower

CAM plants

Found in very hot dry desert areas. Like C4 plants, CAM plants are not susceptible to photorespiration because, unlike C3 and C4 plants, they open their stomata at night, thus conserving water and fixing CO2 and storing it for use during the day to make sugar.


In woody plants, the layer of cells located between the wood and bark of a stem from which new tissues originate


A stem that has a relatively large pith (the central, strength-giving tissue of stem) and usually lives only one or two years

Cane habit

Shrub growth habit in which plants spread by sending up erect new branches, called canes, from their base


Fruits that grow on woody stems called canes, for example, raspberries, blackberries, and their hybrids


The small, leathery, protective leaves that enclose and protect buds, found on rhizomes and are

Cation exchange capacity

A measure of the total negative charges within the soil that adsorb plant nutrient cations

Cell wall

A rigid, structural layer outside the cell membrane in cells of plants, fungi, and some other organisms


A coarse-textured stoloniferous warm-season grass that is adapted in southern Virginia from Martinsville to the coast. It is the lowest maintenance, highest density warm-season grass available.


Typically paired appendages on the abdomen of many species of insect, typically with sensory function


Chemical claws that help hold metal ions, such as iron, in solution, so that the plant can absorb them

Chemical control

Use of pesticides to reduce pest populations. A pesticide is any substance that is used to prevent, destroy, repel, or mitigate any pest

Chilling stress

Stress that occurs in plants sensitive to temperatures in the range of 68-32° F


The primary component of the exoskeletons of arthropods such as crustaceans and insects


Sites of photosynthesis within cells that contain chlorophylls and carotenoid pigments


Yellowing of normally green tissue


The finest soil particles

Climbing roses

Rose bushes that have flowers more than 2 inches across, borne on wood that is 2 or more years old. Canes are larger and sturdier than those of ramblers


Groups of plants that are identical to their one parent and that can only be propagated asexually

coconut coir

A pH-neutral, non-hydrophobic soil amendment that aerates and improves water retention of soil. Readily renewable and more environmentally friendly than peat moss

Cold stratification

Process where seeds are exposed to a period of cold temperatures to break their dormancy cycle


Column-like tree form

Complete flower

A flower with a stamen, pistils, petals, and sepals

Compound leaf

Leaf composed of several separate leaflets arising from the same petiole


Gymnosperms, mostly evergreen but there are notable deciduous species, that have needle, scale-like, or awl-like foliage

Conservation landscaping

Landscape principles that apply best practices for conserving water, soil, and existing native plant communities.


Undesirable substance not normally present, or an usually high concentration of a naturally-occurring substance, in water, soil, or other environmental medium. In more restricted usage, a substance in water that may be harmful to human health.

Cork cambium

Falls outside the vascular cambium and is responsible for growth that replaces the epidermis in stems and roots.

Cork spot

Small dimples on the surface of apples, likely caused by lack of calcium availability in the developing fruit


A solid, swollen stem whose scales have been reduced to a dry, leaf-like covering. They have shapes similar to bulbs, but do not contain fleshy scales.


The petals of a flower


Modified leaves that are found on the embryonic plant and commonly serve as storage organs


A region of compressed stem tissue from which new shoots are produced


Region of compressed stem tissue from which new shoots are produced, generally found near the surface of the soil


Variety bred by people to have desired traits that are reproduced in each new generation (usually through asexual propagation)

Cultural Control

Modifying or disrupting the pest environment to make it less habitable for a pest


Protective film covering the outermost layer of epidermis in leaves, some shoots and some other plant organs.

Cuticle (insects)

The outer covering of the insect, includes most of the material of the exoskeleton


A vegetative plant part which is severed from the parent plant in order to regenerate itself, thereby forming a whole new plant


Duration of light received. For example, Poinsettia, kalanchoe, and Christmas cactus bud and flower only when day-length is short (11 hours of daylight or less).


Plants that form flowers regardless of day length

Deciduous trees

Angiosperm trees that lose their leaves in the fall


Flowering plants with seeds that contain a pair of embryonic leaves (cotyledons). Most of the broadleaf herbs, shrubs, and trees are dicots.


Hand tool with a narrow curved or straight blade on the end of a long stick, also called an asparagus knife


Plants with male and female reproductive organs on separate individuals

Disease triangle

Represents three factors that interact to produce turfgrass disease: the disease causer, the susceptible grass, and a favorable environment


(1) the natural movement of surface water over a land area to a river, lake or ocean (surface drainage), (2) removal of water from a soil using buried pipelines that are spaced regularly and perforated (subsurface drainage).


Biologically diverse communities, combined together with the other non-living (abiotic) elements of the surrounding environment, such as soil, water and sunlight that form a functional system of continuous energy exchange.


Places where two habitat types come together.


Built-in food storage supply in a seed

Enlarged hypocotyl

Storage organ, the swollen portion of the stem below the cotyledon and above the roots


Detachment and transport of soil particles by water and wind. Sediment resulting from soil erosion represents the single largest source of nonpoint source pollution in the United States.


Water lost through stomata when they are open during the day


Process by which a liquid is transformed to the gaseous state

Extensive rejuvenation

Pruning technique that involves complete removal of the entire plant 6-10 inches above the ground


Tree form that looks like a narrow oval


Class of herbaceous vascular plants that reproduce via spores


The ability of soil to sustain plant growth


When materials for plant nutrition are supplied to the environment around the plant

Fibrous root system

Root system in which the primary root ceases to elongate, leading to the development of numerous lateral roots which branch repeatedly and form the feeding root system of the plant

Fine-leaf fescues

Includes creeping red, hard, and chewing fescues. Exhibits the best tolerance of shade, drought, low-nitrogen, and acid soil


Temporary condition of partial or complete inundation of normally dry land areas from the overflow of inland or tidal waters or from the unusual and rapid accumulation of runoff.


Raspberry and blackberry plants that bear fruits on the second year cane

Flower bud

A but that contains partially preformed flower tissue

Flower primordia

The small buds at the end of stems from which flowers develop

Freezing stress

Stress that occurs in plants sensitive to temperatures below the freezing point of water or 32°F


Growth on the external tissues of a plant


A group of somewhat closely related individuals (a group name) comprising one or more species


Herbaceous plants with underground storage organs, rather than fibrous root systems

Gradual rejuvenation

Pruning technique that removes growth gradually


Water that fills voids, cracks, or other spaces between particles of clay, silt, sand, gravel or rock within a saturated zone or formation (aquifer) below the soil surface.

Guard cells

Epidermal cells located around a stoma that help regulate gas exchange by opening and closing


Seed-bearing vascular plants that produce exposed seeds, or ovules, which are usually borne in cones


The area within an ecosystem where an animal is able to secure the food, water, cover and space it needs to survive and reproduce.

Hand cultivators

Digging hand tool with tines


The process of altering the quality of plant growth to withstand the change in environmental conditions which occurs when plants are transferred from a greenhouse or home to the garden


A plant’s ability to withstand low winter temperatures and remain aesthetically pleasing

Heading cuts

Pruning cuts that reduce the height or width of a plant by cutting back lateral branches and removing terminal buds; made at nodal areas either above side branches or buds

Hedge shears

Shears with long, flat blades and relatively short handles, one for each hand


An organized and cataloged collection of such specimens, usually at a university or a museum.


Tool with a blade at a right angle to the handle. Examples may be pointed with a heart-shaped blade or have a narrow blade to slice through soil.


An insect that undergoes complete metamorphosis with four distinct stages of development


A plant that another organism (such as an insect or virus) lives on


The portion of organic matter that remains after most decomposition has taken place


A genetic cross of two different plants, usually from two different varieties of the same species


The portion of a seedling between the radicle and the first leaf-like structure


To become established on/in the plant and initiate disease development


Process by which water (surface water, rainfall, or runoff) enters the soil.

Infiltration rate

Quantity of water that enters the soil surface in a specified time interval. Often expressed as a volume per unit of soil surface per unit of time (in3 per in2 per hour). Soil surface wetness, soil texture, residue cover, precipitation rate, irrigation application, topography, and other factors control the infiltration rate.


Part of a pathogen that can cause infection

Integrated pest management

An ecosystem-based strategy that focuses on long-term prevention of pests or their damage through a combination of appropriate control tactics. These tactics can be preventative, curative, or both and are often combined to provide the best possible results.

Intergeneric hybrid

Cross between two genera (a very rare occurrence)


Section of the stem between two successive nodes

Interspecific hybrid

A cross between different species of the same genus

Intra-specific variation

Variation within a species


Controlled application of water to land to supply plant water requirements not satisfied by rainfall

Kentucky bluegrass

Turfgrass that provides lush, blue-green, fine-bladed lawns. Best suited to areas in and west of the Blue Ridge Mountains and north of Richmond.

Landscape design

The process of planning and organizing the natural and man-made parts of the landscape into an aesthetic, functional, and environmentally sustainable space

Lateral buds

Buds borne on the sides of a stem

Lateral root

Side or branch root that arises from another root. Also called a secondary root.


Removal of dissolved chemicals from soil caused by the movement of a liquid (like water) through the soil

Leaf bud

Bud composed of a short stem with embryonic leaves


A well defined area of diseased or injured tissue, often dead spots or areas. Lesions are often a primary symptom.

Light intensity

Influences the manufacture of plant food, stem length, leaf color, and flowering

Light quality

The spectral distribution of light, or the number of different colored photons emitted by the light source (for example, blues, reds, greens)


A textural class of soil that has moderate amounts of sand, silt, and clay


Plants form flowers only when day lengths exceed 12 hours (short nights).

Lopping shears

Long handled shears that are operated with both hands


Chemical elements required in large amounts for plant growth and development. These are: Carbon (C), Hydrogen (H), Oxygen (O), Nitrogen (N), Phosphorus (P), and Potassium (K), Calcium (Ca), Magnesium (Mg), and Sulfur (S).

Mechanical/physical control

Using hands-on techniques or simple equipment/devices to reduce or prevent the spread of pest populations


An area of cell division and growth Cells in the meristem can develop into all other tissues and organs found in plants.


Zones of atypical high or low temperatures


Chemical elements required in small amounts for plant growth and development. These are: Iron (Fe), Zinc (Zn), Manganese (Mn), Boron (B), Copper (Cu), Molybdenum (Mo), Chlorine (Cl)


A small pore located in a seed's seedcoat that allows water absorption and gas exchange

Miniature roses

Rose bush 6 to 12 inches high with tiny blooms and foliage


Grass and grass-like flowering plants with seeds that typically contain only one embryonic leaf


Plants with male and female reproductive organs on the same plant

Mounding habit

Shrub growth habit in which plants often have soft, flexible stems, small leaves, and are often used in mass plantings

Multiple fruits

Fruits derived from a tight cluster of separate, independent flowers borne on a single structure


Cultivars of native species

Native plants

Plants that occur in the region in which they evolved.


Leaf venation pattern in which veins branch from the main rib(s), then subdivide into finer veinlets which then unite in a complicated network


The part of the stem where one or more leaves are attached

Nonpoint source pollution

Pollution originating from diffuse sources on the landscape. Examples include runoff from fields receiving manure applications, runoff from urban landscapes, or roadbed erosion in forestry. It has been estimated that NPS pollution accounts for more than one-half of the water pollution in the United States today.


Organelle that contains the genetic information for the organism and controls the activities of the cell

Open pollinated

Seed that is self or cross-pollinated by wind or insects and is produced by isolating plants from other plants of different varieties to produce seed that is "true to type"


Leaf arrangement where leaves are positioned across the stem from each other, two leaves at each node.


Methods that involve growing and maintaining healthy plants without using synthetic (manmade) fertilizers, pesticides, hormones, and other materials

Organic matter

Plant and animal material in varying stages of decomposition present in soil.

Overhead watering

Watering system in which water is sprayed down on crops, directly wetting the crop surface


Leaf shape in which leaflets form and radiate from a single point of attachment


Leaf venation pattern in which numerous veins that run essentially parallel to each other and are connected laterally by minute, straight veinlets

Parent material

Bottom soil horizon, decomposed rock that has acquired some characteristics of the subsoil and retained some characteristics of the rock from which it weathered.

Peat moss

Decomposed mosses and other living material found in peat bogs


Peds are made up of mineral particles (clay, silt, sand) and organic matter; held together by the electrical charges on the surfaces of the minerals and organic matter


Tree form in which branches hang down, also called weeping


Plants that live for many years. May be herbaceous or, if significant xylem develops in the stem and the top persists, may be classified as woody.

Perennial ryegrass

A fine-medium textured grass that mixes well with Kentucky bluegrass

Perfect flower

A flower with functional stamens and pistils


A sterile, porous soil amendment material produced by heating volcanic rock to approximately 1800ºF


Any substance that is used to prevent, destroy, repel, or mitigate any pest. Can be synthetic (man-made), or natural products derived from plants, microorganisms, or inorganic elements


Modified leaves, typically brightly colored, segments of a flower’s corolla


Stalk that supports the leaf blade


Visual appearance as a result of DNA expression


Transport tissue in vascular plants, transports the soluble organic compounds made during photosynthesis to the rest of the plant in a process called translocation


Process by which green plants and some other organisms use sunlight to synthesize foods from carbon dioxide and water. Generally involves the green pigment chlorophyll (in green plants) and generates oxygen as a byproduct.


Leaf shape in which leaflets are attached along an extension of the petiole


The female part of the plant that consists of the stigma, style, and ovary

Pistillate flowers

Flowers are those that possess a functional pistil(s), but lack stamens

Plant community

The collection of plant populations found in that area

Plant nutrition

The needs and uses of the basic chemical elements in the plant


Small squares/circles of sod grown in a tray


Embryonic shoot

Point source pollution

Pollutant loads discharged at a specific location from pipes, outfalls, and conveyance channels. Point source discharges are generally regulated through the National Pollution Discharge Elimination System (NPDES) permitting procedures established by the EPA. Point sources can also include pollutant loads contributed by tributaries to the main receiving stream or river.

Pole pruners

Shears with a hooked blade above and a cutting blade beneath. The cutter is on a pole and is operated by a cord or chain pulled downward


Any substance of such character and in such quantities that when it reaches a body of water the effect is to degrade the receiving water perhaps to a point rendering it unfit for some specified designated use


Alteration of the physical, biological, chemical, and radiological integrity of water due to human activities ‚ any unwanted contaminating property that renders a water supply unfit for its designated use.


Rain, sleet, snow, or hail that falls to the earth as the result of water vapor condensing in the atmosphere.


In grafting, the ability of rootstocks to induce fruitfulness. Precocity is measured in apple rootstocks by observing the length of time from planting to when the cultivar produces flowers.


Sprouting the seeds before they are planted in pots (or in the garden)


Raspberry and blackberry plants that bear fruits on the first year cane (shoot) which are ready for harvest in late summer


Source of plant material


Primary root, first organ to appear when a seed germinates

Rain garden

A shallow landscaped depression that filters polluted stormwater before it evaporates, evapo-transpires through the plants, or percolates through the soil into the groundwater.


Tool with a long handle and crossbar with a toothed comb, helpful in spreading mulches and smoothing seedbeds

Rambler roses

Rose bushes that have clusters of flowers, each usually less than 2 inches across

Relative humidity

The ratio of water vapor in the air to the amount of water the air could hold at a given temperature and pressure, expressed as a percent


Process by which plants use the sugars produced during photosynthesis (plus oxygen) to produce energy


Specialized stem that grows underground and sends out roots and shoots from nodes


Design principle of even repetition, and it directs the eye in the landscape through continuity and flow


Pertaining to the banks of a river, stream, or other typically, flowing body of water as well as to plant and animal communities along such bodies of water. This term is also commonly used for other bodies of water, e.g., ponds, lakes.

Root cap

Outermost tip of the root, consists of cells that are sloughed off as the root grows through the soil

Root hairs

Projects of root epidermal cells, important in absorption of nutrients, plant anchorage, and more


In grafting, the piece of shoot that provides the new plant’s root system and sometimes the lower part of the stem, the lower portion of the graft

Rose standard

Tree rose, a Hybrid Tea, Grandiflora, or Floribunda budded at the top of a tall trunk


A circular arrangement of leaves, usually near the soil (for example, dandelion)

Rotary tiller

Power toll with a series of rotating tines used for working soil several inches deep


A specialized stem that grows on the soil surface and forms a new plant at one or more of its nodes. A type of stolon.


Part of rainfall or snowmelt that does not infiltrate the soil but flows over the land surface toward a surface drain, eventually making its way to a stream, river, lake or an ocean. It can carry pollutants into receiving waters. Also known as stormwater.


Members of the Juncaceae family of flowering plants; distinguishable from grasses and sedges by their round (and frequently unbranched) stems filled with pith (not hollow)


Coarser mineral particles of the soil


Design principle that refers to the size relationship or proportion between different parts of a landscape. This could be between buildings and plants, plants and plants, or plants and people


Breaking, scratching, or softening the seed coat so that water can enter and begin the germination process


In grafting, the piece of shoot with dormant buds that will produce the stem and branches on the upper portion of the graft


Hardened plates joined together forming the hard surface of insects

Secondary growth

Growth in lateral meristems that causes increase in girth


Members of the Cyperaceae family of grass-like monocotyledonous flowering plants; distinguishable from rushes and grasses by their triangular stems


In the context of water quality, soil particles, sand, and minerals dislodged from the land and deposited into aquatic systems as a result of erosion.


Small, green, leaf-like structures on the base of the flower that protect the flower bud

Sexual propagation

Involves the union of the sperm (male) with the egg (female) to produce a seed


A young stem with leaves present


Plants that form their flowers only when the day length is less than about 12 hours in duration.


Tool used for digging and lifting loose soil or other materials


Perennial woody plants that have one or several main stems, and usually are less than 12 feet tall at maturity.


Structures or products of the pathogen itself on a host plant, for example, mold, fungal fruiting bodies, or bacterial slime/ooze


Relatively fine soil particles that feel smooth and floury. When wet, silt feels smooth but is not slick or sticky.

Simple fruits

Fruits that develop from a single ovary

Simple leaves

Leaves with a leaf blade that is a single continuous unit


Upper layer of soil with grass growing, often harvested and rolled

Soluble salts

Minerals dissolved in water that can accumulate in potted plants

Spading fork

Digging tool with strong, flat tines that is ideal for breaking and turning heavy soils and for loosening subsoil layers when double digging a bed


A group of individuals that can be characterized by a set of identifiable characteristics that distinguishes them from other types

Species diversity

The use of many varied taxa (family, genus, species) within an “area”, where an area may range from a residential site to municipal or larger sites

Specific epithet

The second word of the Latin binomial that usually functions as an adjective (or sometimes named after an individual) and indicates or describes the member of the genus


Specialized modified leaves that protect the plant


The stems from shredded sod. Sprigs should include leaves, a stolon, and roots

St. Augustinegrass

A coarse-textured stoloniferous warm-season grass that has the best shade tolerance of warm-season grasses.


The male reproductive organ. It consists of a pollen sac (anther) and a long, supporting filament

Staminate flowers

Flowers that contain stamens, but no pistils


Horizontal stem that is fleshy or semi-woody and lies along the top of the ground


Openings in leaves that allow passage of water and gasses into and out of the leaf. Singular: stoma

Storage leaves

Serve as food storage organs, found on bulbous plants and succulents


Any change in environmental conditions that adversely affects survival, growth, development and yield in plants

Stubble mulch

A stubble of crop residue left in place for winter


Usually finer and firmer than the surface soil. Organic matter content of the subsoil is usually much lower than that of the surface layer.


A grouping within a species used to describe geographically isolated variants


Vigorous shoots growing from the trunk or roots

Surface horizon

Contains more organic matter than the other soil layers. Organic matter gives a gray, dark-brown, or black color to the surface horizon


Physical expressions of disease in the host tissue, e.g., changes in color, appearance, integrity, etc.

Tall fescue

A fine to moderate coarse-textured turfgrass which is tolerant of a wide range of soil types and climatic conditions


Formed when the primary root continues to elongate downward into the soil and becomes the central and most important feature of the root system, with a somewhat limited amount of secondary branching.


Any taxonomic group/category


Perennials native to moderate temperature regions without extreme cold or a tropical climate

Terminal bud

Buds located at the apex of a stem

Terminal buds

Buds located at the apex of a stem


An organic mat of stems that forms between the mineral soil and the turfgrass canopy


The daily range of temperatures a plant is exposed to

Thinning cuts

Also called reduction cuts, pruning cuts that remove branches at their points of origin or attachment

Topping cuts

Height-reducing pruning cuts made indiscriminately in internode areas


Process by which a plant loses water, primarily from leaf stomata.

Tree-like shrubs

Shrubs that have woodier, finely divided branches and can be pruned as a single-trunk or multi-stemmed trees


Perennial woody plants, usually with one main trunk and usually more than 12 feet tall at maturity


A small hand-tool for digging


A main stem of a woody plant


Enlarged portion of an underground stem. The tuber, like other stems, has nodes that produce buds.

Tuberous root

Modified lateral roots that are enlarged to function as an underground storage organ. Found in dahlia and sweet potato.

Tuberous roots

Underground storage organ

Tuberous stem

Shortened, flattened, enlarged, and underground stem. Examples are tuberous begonia and cyclamen.


Measure of the cloudiness or opaqueness of the water expressed in nephelometric turbidity units (ntu). The turbidity is influenced by the amount and nature of suspended organic and inorganic material in water. Typically, higher concentrations of the suspended material equal greater turbidity. The source of turbidity could be sediment (fine sand, silt, and clay), organic material, particles of iron and manganese or other metal oxides, rust from corroding piping, algae, carbonate precipitates, etc.


Turgidity (swelling) and resulting rigidity of plant cells or tissues, typically from the absorption of fluid


A stem that is less than one year old and has no leaves since it is still in the winter-dormant stage


Design principle created by repetition of shapes, lines or colors, the grouping or arranging different parts of the design to appear as a single unit


A large liquid-filled cavity within a cell


A subpopulation of a species that has a distinctive trait that distinguishes it from the rest of the species and occurs in nature

Vascular bundle

Part of the transport system in vascular plants that includes the xylem, phloem, and other tissues

Vascular cambium

The main growing tissue of stems and roots in most plants. It produces the secondary xylem and secondary phloem.

Vegetative bud

A bud that contains partially preformed leaf and stem tissue


Compost made by worms as they digest plant material


A sterile, lightweight, mica product used as a soil amendment


Cool the plant in order to encourage flowering


Vertical mowing to remove thatch buildup


A plant that develops long, trailing stems that grow along the ground unless they are supported by another plant or structure

Voucher specimen

A specimen of a species that depicts clearly its most important physical characteristics and structures.

Water table

The depth at which soils are fully saturated with water, the upper surface of an unconfined aquifer.

Water-holding capacity

The amount of water that a soil can hold for crop use


Area that drains or contributes water to a particular point, stream, river, lake or ocean. Watersheds are also referred to as basins. Watersheds range in size from a few acres for a small stream basin, to large areas of the country like the Chesapeake Bay Basin that includes parts of six states.


Vigorous, usually-upright shoots that grow from the trunk or branches


Deep hole or shaft sunk into the earth to obtain water groundwater.


Transitional lands between terrestrial and aquatic systems where the water table is usually at or near the surface, or the land is covered by shallow water. Wetlands are those areas where water saturation is the dominant factor determining the nature of soil development and the types of plant and animal communities living in the surrounding environment.


Leaf arrangement where leaves are arranged in circles along the stem.

Wide row planting

Planting in such closely-spaced bands rather than in rows of individual plants


Plantings of trees and shrubs placed strategically to slow winds

Witch’s broom

deformity in a woody plant where a mass of shoots grows from a single point

Woody plants

Perennials (life span ranges from decades to centuries, or in some cases millennia) in which the shoot (above ground portion of the plant) persists during plant dormancy (usually late-autumn to early-spring)


Transport tissue in vascular plants, transports water from roots to stems and leaves (also transports nutrients)


A warm-season grass of fine to medium texture that turns brown with the first hard frost in the fall and greens up about mid-May.


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Virginia Cooperative Extension Gardener Handbook Copyright © 2023 by Virginia Cooperative Extension, Virginia Polytechnic Institute and State University is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License, except where otherwise noted.

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