The entrance or taking-in of a chemical or nutrient into the plant.

Active Ingredient

The chemical in a pesticide that controls the target pest.

Acidic Soil

The acidity of soil is determined by the concentration of hydrogen (H) ions. The more hydrogen there is, the more acidic the soil. Soil with a pH between 0 and 7.0 is considered acidic. To raise soil pH add lime.


A measure of land totaling 43,560 square feet. A square acre is 208.75 feet on each side.

Aeration (core aeration)

Lawn aeration involves making holes in the lawn either by pushing a rod into it or by "coring", extracting a plug of soil. Aerating a lawn provides the following benefits to the lawn and its root system: Oxygen gets to the roots and the soil allowing it to "breathe". Organic fertilizers and nutrients get access to the root system. The soil can better absorb water and allow it to reach the root system. It helps to break up thatch. It loosens up compacted soil allowing the root system to grow.


The presence of oxygen in contrast to an anaerobic condition which is the absence of oxygen. (See anaerobic)

Alkaline Soil

The alkalinity of a soil is determined by a pH between 7.0 and 14. Determining whether a soil is alkaline is based on the concentration of hydrogen (h) ions; the less hydrogen, the more alkaline the soil. To lower soil pH add sulfur. In general, some nutrients cannot be efficiently absorbed by plant roots if soil pH is too high. (See sulfur/sulphur)


Substances added to the soil to improve moisture retention, oxygen level and nutritional content.


The absence of oxygen within an environment. (See aerobic)


Annual plants perform their entire life cycle from seed to flower to seed within a single growing season. All roots, stems and leaves of the plant die annually. Only the dormant seed bridges the gap between one generation and the next. The seed can stay in the soil for years and compete with grass for nutrients.

Annual (Weeds)

Annual weeds grow and sprout quickly as warmer weather arrives. They flower, set seeds and die in the same year when colder weather arrives. If the weed gets to the point of setting seeds, the seeds can stay in the soil for years waiting for the right conditions to germinate. Annual weeds reappear from year to year and can compete with grass for nutrients.

Annual Bluegrass (Poa annua)

Annual bluegrass, Poa annua, is the most common and widely distributed grassy weed in the world. It typically grows in fairway or lawn settings and develops dense patches that can adapt to most mowing heights, even the lowest settings. Bluegrass typically germinates year round and is fueled by cool moist conditions. (See Kentucky bluegrass)

Annual Ryegrass (Lolium multiflorum)

Annual ryegrass is a cool-season grass well adapted to sunny conditions and moderate temperatures. Also known as Italian ryegrass or wintergrass, it is often sown at high rates to overseed warm-season turfgrasses for fall, winter, and early spring color or to provide temporary cover for soil stabilization. It is not otherwise used for turf. Annual ryegrass dies in the late spring to early summer. It often turns yellow and dies before warm-season grasses come out of dormancy.

Arthropod (see insects)

Invertebrate having jointed limbs and a segmented body with an exoskeleton made of chitin. Sample arthropods are crabs, insects, lice, shrimp, ticks, spiders, scorpions, centipedes and millipedes. Arthropods and insects are members of the phylum Arthropoda, but ticks (for example) are members of the class Arachnida, while insects belong to the class Insecta.

Bahiagrass (Paspalum notatum)

A warm-season coarse grass that grows well along the southern coastline in Florida and in southern California.

Beneficial Insect

An insect that attacks lawn/garden pests and controls their population.

Bentgrass (Agrostis)

There are three types of bentgrass: the Colonial, Creeping, and Velvet. Each retains particular qualities relating to climate, salt tolerance, depth of color, and texture. Bentgrass is a cool-season lawn grass. Bent can be planted from seeds or sod and provides a beautiful golf-like turfgrass lawn in Northern areas. Bents requires high amounts of lawn care and maintenance.


A plant starting from seed and requiring two years to complete its life cycle.

Biennial Weeds

Biennials normally reproduce by means of seed but, unlike annuals, they rarely flower and set seed in their first year. The first year’s growth represents a vegetative phase during which the plant grows and accumulates food reserves followed by flowering and seed production in the second year. After the plant flowers and sets seed it normally dies. Management methods are similar to those employed against perennial broadleaf weeds such as chickweed, dandelion and clover.


An insect with several different species that typically attacks Kentucky bluegrass, but also attacks perennial ryegrass, fescues and other lawn turfgrass. Billbug larvae are grayish in color and have no legs, but push and pull themselves through the soil like a worm. Only a few species cause significant harm, but if infestation is heavy preventative or corrective lawn care measures should be taken to curtail future damage.


Capable of being broken down into simpler compounds by microorganisms. Organic materials such as compost (made from plant wastes), certain animal manures (chiefly composted cow, chicken, or horse manures) and other naturally occurring substances. Grass clippings are also biodegradable and add nutrients to the soil.


Pertaining to biology or to life and living organisms.

Biological Pest Control

Using living organisms (beneficial insects, bacteria) to destroy insect pests.


A biosolid is the nutrient-rich organic material left over from the treatment of sewage sludge.

Black Water

Black water is wastewater used in toilets and designated for sewage systems.


The grass leaf blade appears above the sheath and is typically long and narrow with a tapered point.

Blend, Seed

A blend of grass seeds containing only one species of grass, but multiple subspecies (also called varieties or cultivars). Seed blends are highly adaptable, provide different germination speeds and the variety selection can be tailored to the strengths and weaknesses of a lawn. The blend can be formulated to grow grass better in shady or sunny areas. Blended lawns can also help prevent damage from some lawn diseases.

Botanical Insecticide

Derived from plants, these organic pesticides can provide a remedy to a large number of pests. Although they are natural, botanical insecticides do have drawbacks. Because of their rapid degradation they must be applied frequently and precisely. Many are broad-spectrum insecticides and will harm beneficial insects. Several botanical insecticides also are harmful to fish or other wildlife. Botanical insecticides are often more expensive to purchase than synthetic pesticides.


Application of a pesticide, fertilizer, seeds, etc., over an entire area.


A term applied to non-grass-like plants often used in the context of weed control. Examples include dandelion, chickweed and henbit. Broadleaf plant characteristics are widely varied. Broadleaf plants can have a taproot, a bulbous root, or fibrous roots. They generally have showy flowers.

Broadleaf Herbicide

A weed killer designed to specifically control broadleaf weeds without damaging desirable turf.

Broadleaf Weed Control

The control of unsightly broadleaf weeds. Broadleaf weeds can increase lawn care and mowing requirements and delay the recovery of growing grass. For total lawn care and broadleaf weed control regular mowing, along with proper fertilization, or chemical control can eliminate these types of weeds.

Brown Patch

A fungal disease that typically occurs during the warmer months and results in unattractive patches of browned or blighted turf. Avoid over fertilizing to help to prevent brown patch.

Buffalograss (Buchloe dactyloides)

Buffalograss is a native warm-season turfgrass. Its tolerance to prolonged droughts and to extreme temperatures together with its seed producing characteristics enables buffalograss to survive extreme environmental conditions. Buffalograss is best adapted to low rainfall areas (15 to 30 inches annually) or areas that receive thorough, but infrequent irrigation.


Any of various grasses of many genera that grow in tufts or clumps rather than forming a sod or mat; chiefly of western United States. A non-spreading grass lacking rhizomes and stolons.

Bermudagrass (Cynodon dactylon)

A warm-season turfgrass used on golf courses, athletic fields and lawns. It quickly recovers from damage, spreads easily, and tends to grow well in poor soils. It is best used if lawn care is done on a very regular basis and the rainfall/watering is frequent. It grows rapidly and new lawns can experience growing grass and full coverage in 60-90 days.

Carbon Footprint

According to the Environmental Protection Agency (EPA), "carbon footprint" refers to the amount of greenhouse gases emitted into the atmosphere each year by an individual, household, building, organization or country. It is usually measured in pounds of carbon dioxide equivalents, and it typically includes both direct and indirect emissions. Environmentally friendly lawn care practices can help decrease your carbon footprint. A healthy lawn can absorb a great deal of carbon dioxide.

Carpetgrass (Axonopus affinis)

Carpetgrass is a warm-season perennial, coarse-leaved, creeping grass. It grows better on low, wet soils than do other grasses. It will grow well in either sun or shade but is less shade tolerant than St. Augustine and Centipede grass which it resembles. Carpetgrass may be planted by seed or sprigs. Carpetgrass is recommended only for lawns on wet, low fertility, acid (pH 4.5-5.5), sandy soils where ease of establishment and care is more important than quality. Its chief disadvantage is rapid seedhead production.


An inert material added to an active ingredient to prepare a formulation of a pesticide or fertilizer.

Castings, Earthworm

The excretions left behind by worms after they digest organic matter. Earthworm castings can enhance plant growth and earthworm activity can help improve lawn aeration and a lawn’s water retention.

Centipede Grass (Eremochloa ophiuroides)

A very low maintenance warm-season grass that grows well in sandy or clay based soil. Centipede grass needs a minimal amount of grass care, including little fertilization or mowing, Grows slowly and may take a little bit longer to repair.

Certified Seed

A type of seed that is produced under strict certification standards in order to maintain varietal purity. Certified seed must pass field inspection, be conditioned by an approved seed conditioning plant and be sampled, and pass lab testing before it can be marked and sold as certified.

Chewings Fescue (Festuca rubra ssp. commutata)

Chewings Fescues are known for their fine leaf texture. They are shade and drought tolerant cool-season grasses. They require less frequent mowing than ryegrass, tall fescue or Kentucky bluegrass, and perform well in low fertility areas.


The green pigment in leaves.

Chinch Bug

A small black bodied insect with wings that typically infests different types of grass. Chinch bugs infect growing grass and they can injure or impede growth.


Localized areas of disease damage in turf that are circular and usually greater than four inches in diameter.


One of the particles in the making of soil. A clay soil is one that is made up of mostly clay particles. Clay tends to be nutrient rich which is good for attracting positively charged particles for healthy plant and grass growth. However, clay can also be slow draining, easily compacted making it difficult for root growth, and more alkaline.


Refers to the lawn clippings from mowing. Clippings left on a lawn can help improve the turf and reduce fertilization needs. If you prefer picking up your grass clippings, they can be composted or recycled.

Coarse Fescue (Festuca arundinacea) [also called Tall Fescue]

A wide leafed cool-season turfgrass, sometimes called Tall Fescue. Turf-type Tall Fescues are desirable and being bred for weed control and prevention programs.

Colonial Bentgrass (Agrostis capillaris)

A cool-season grass that has been in the United States since the early days of the colonists. This variety was brought from Europe to reproduce the fine lawns of their homeland. This grass thrives in cool coastal weather. It is adapted to coastal regions in northern California where it is used for general lawn areas. It does best in cool, humid weather and can tolerate some shade.

Complete Fertilizer

Any fertilizer product containing at least nitrogen, phosphorus, and potassium.


The rich organic material that results from the process of decomposition of plant and animal waste.


Soils that are subject to heavy traffic are prone to compaction (compression). Compacted soils reduce drainage, increase runoff, and inhibit root growth. Aerifying (aeration) can help alleviate compaction.

Contact Herbicide

A weed killer that only injures the portion of the plant or plant soil that it contacts.

Cool-Season Turfgrass

Turfgrass species with optimum growth at temperatures between 60 and 75°F (15.5°C to 23.8°C). Cool-season grass varieties include creeping bentgrass, fine fescue, tall fescue, Kentucky bluegrass, annual ryegrass and perennial ryegrass.

Core Aeration (Cultivation)

Removal of soil cores from a turf with hollow tines or spoons which, as with other methods of aeration, loosens the soil to help alleviate soil compaction, reduce thatch and help water and air circulate to the roots of growing. Regular lawn core aeration can prevent lawn diseases and make grass healthier. Cores left on the lawn will break down and help to increase microbial decomposition of dead organic material (thatch).


Removal of soil cores from a lawn with hollow tines or spoons.

Crabgrass (Cigitaria)

A member of the grass family Poaceae that is often the target of weed control programs because its creeping stems root freely throughout lawns.

Crane Flies

Crane Flies are insects that are about 1-inch long with wings and long legs. In larvae form these flies resemble brown worms known as "leatherjackets." Leatherjackets feed on grass roots, causing the most damage to growing grass in spring. Thatch often provides food for these larvae. Proper lawn treatments, such as core aeration, can prevent infestations.

Creeping Bentgrass (Agrostis palustris (or) Agrostis stolonifera)

A cool-season grass native of Europe and parts of Asia. It requires cool, humid environments. This grass forms a dense mat by creeping stolons and has a shallow root system with long slender leaves. It is used extensively in lawns, golf courses, athletic fields for the creeping, dense growth, beautiful coloration and short mowing tolerance. It is used primarily on golf putting greens because of the denseness and mowing qualities. It is adapted to cool, humid regions and prefers sunny areas but will tolerate some shade. It tolerates low temperatures but will discolor early in the fall.

Creeping Red Fescue (Festuca rubra ssp. rubra)

A cool-season grass used in cool, shaded, mountain sites, such as camps, resorts, and cabins where low input of mowing, fertilization, and irrigation is desired. It does not do well in hot climates, except in shady, dry situations. In areas where Kentucky bluegrass does well, red fescue forms an excellent companion grass to increase shade tolerance. Red fescue germinates and establishes slowly. It is moderately wear resistant.

Crop Seed

Any seed grown as an agricultural crop, such as perennial ryegrass or wheat.


The crown refers to the part of a plant where the root and stem meet. Having a healthy crown is essential to growing grass. It is the most important part of the grass plant because it is the origin point for leaves, secondary roots, and other stems.


A cultivated variety of a species. A label given to plants that are cultivated for a specific purpose. It's often recommended that several cultivars be blended together, for easier turf care. Lawn diseases and other issues can be reduced by choosing specific cultivars for an optimal grass blend or mix.


To promote, improve or begin plant growth by labor and attention.


In turf, the working of the soil without significant damage to the turf.

Cultural Practices

Practices such as core aeration that help maintain a healthy balance between the soil, air, and water in your lawn. Total lawn care involves developing a set of cultural practices appropriate for the surrounding environment.

Dallisgrass (Paspalum dilatatum)

A cool-season grass that invades turfgrass. In Bermudagrass, dallisgrass leaves grow much faster, causing more frequent mowing and lawn care. Weed control and prevention is often necessary to curb Dallisgrass.


An herb with long roots, deeply rooted leaves and a yellow flower that turns into a white, feathery-like ball of seed. Dandelions are perennial weeds that crowd growing grass.


The rotting or decaying of an organic substance.


The process of removing dead stems and built-up organic matter that locks in moisture and which can promote grass disease and insect infestations.


An interaction between a grass plant, pathogen and its environment that impairs the normal development of a plant.

Disease Control

Methods taken to prevent growing grass from an abnormal condition that may cause death.

Dollar Spot

Refers to a lawn disease affecting turfgrass. Common signs of this grass disease are a circular, straw-colored spot in the lawn.


A condition of significantly reduced activity where little if any growth occurs and where rates of physiological activities, like photosynthesis, are minimal or non-existent. Similar to hibernation in that some grasses go dormant to prevent dying under extreme temperatures. Grass still needs to be lightly watered during dormancy.


Resting stage for a grass plant when its life appears to come to an almost complete standstill.


Associated with wind movement that can push or force weed control and pesticide chemicals beyond an intended area. When spraying a chemical care needs to be given to wind movement. Growing grass or other plants adjacent to target areas could be affected by drift.


Extended periods of dry weather often causing moderate to severe stress in turf. It can be particularly damaging to lawns when combined with high temperatures.

Drought Tolerance

The grass plant's ability to withstand extended periods of dry conditions without incurring permanent damage.

Drought Stress

The stress placed on plant life by dryer than normal conditions. Growing grass is affected when temperatures become hotter than normal and it receives little or no irrigation. Some grasses can protect themselves by going dormant but even dormant grasses require light watering.


The interaction of turfgrass with other plants, animals and their surrounding environment.

Effluent Water

The sewage or industrial liquid waste that is released into natural water by sewage treatment plants, industry or septic tanks.


One liquid suspended in another.


A living fungi or algae that grows in certain types of grasses. In turfgrass it is often a fungus that secretes a substance that repels insects.


Water lost back to the atmosphere through the vaporization of water.


The combination of evaporation (water loss from land and water surfaces) and transpiration (water loss from plants).


The surroundings and conditions in which your lawn, trees and other plants live. On a broader scale, the circumstances, objects, or conditions by which one is surrounded.


Complete elimination of something, such as a pest, from an area or the environment.


The wearing away and transportation of soil from land areas by wind or water.

Fairy Ring

A lawn disease where fungi in the form of a ring kill the grass beneath it. There are many different kinds of fungi that can cause a fairy ring. Proper lawn care prevents this lawn disease and other grass diseases.


An organic or inorganic material that is applied to the soil or a plant to improve its nutrient content. Organic or inorganic plant foods can be either liquid or granular.

Fertilizer Analysis (see N-P-K)

The amount of each nutrient (N-P-K) in a fertilizer container expressed as percent of the total weight. For example a bag of fertilizer that reads 5-10-5 means: 5% of (N) Nitrogen, 10% of (P) Phosphorus and 5% of (K) Potassium.

Fertilizer Burn

Plant injury (and often death) caused by contact with high concentrations of certain fertilizers.

Fibrous Roots

A root system made up of many threadlike members of more or less equal length and size, like fine branching hairs which have grown to create a dense mat.

Fine Fescue (Festuca sp.)

Fine fescues are composed of a group of Festuca species and subspecies. All are fine-textured, cool-season turfgrasses that are inherently low maintenance, shade and drought tolerant. Fine fescues typically require less water, sunlight and fertilizer than other cool-season species. In general, this group of grasses performs well in the cooler, more temperate climates of the world. Fine fescues are among the most complex groups of turfgrasses, comprising at least five different types - - Hard fescue, Chewings fescue, (blue) sheep fescue, creeping red fescue and slender creeping red fescue.

Fire Ants

Small, reddish ants named for their burning sting which can cause serious medical problems. Fire ants build dirt nests that form mounds, usually in open grass settings. They are typically found in the southern United States and other areas that do not freeze in winter.

Flea and Tick Control

Lawn repair and renovation services are often the best solution to controlling flea and tick populations. A lawn care service professional normally decides the best measures for both preventive and/or curative flea and tick control.

Fungal Disease

Most turfgrass diseases are caused by fungi, and even though fungi are microscopic organisms, some produce larger structures at certain times in their life cycle that can be seen with the naked eye. Fungal signs include blisters on leaves, fruiting bodies, mushrooms, puffballs, pustules on leaves, spore masses, etc.


A pesticide used to kill fungi.


A group of organisms that don't use the sunshine to produce food. Mushrooms, a fungus, appearing in an arc formation are often indicators of fairy ring, a lawn disease.


The process of a seedling sprouting from a seed.


The beginning stages of growth for a plant rising from its seed. In terms of grass, lawn care depends on properly encouraging seed germination.

Goosegrass (Eleusine indica)

A troublesome grassy weed that is common on athletic fields, golf courses or other shortly mowed turfgrass areas.


Small particles of a material. Granular formulations containing fertilizer and/or pesticide can be used in a lawn care program.

Grass (see turfgrass)

Short vegetation consisting of typically short plants with long narrow leaves, growing wild or cultivated on lawns and pastures. Herbaceous monocot members of the Poaceae Gramineae family, grasses may vary in length, texture, width, and color.


Leaving grass clippings on the lawn when mowing to return nutrients back to the soil.

Gray Water

Gray water is defined as the wastewater produced from baths and showers, clothes washers, and lavatories that does not contain serious contaminants as would wastewater from toilets or diapers. Gray water may be recycled with little or no treatment for non-potable uses such as landscape irrigation.


An aphid, or very small insect, that usually attacks turfgrass.


Areas of outdoor landscape containing well-maintained grasses and non-weed plant life. Greenspace often refers to a planted aesthetic or recreational space in an otherwise urban environment.


A horticultural term applied to low-growing vegetation covering the ground; may refer to broadleaf plants as well as lawn grasses.

Ground Ivy

A perennial plant that crowds growing grass and is particularly difficult to control without a proper weed control program.


Grubs are the larvae stage of various species of beetles which feed on grass roots and attract moles. The larvae have soft, off-white bodies and dark heads. All but the green June beetle larvae have six well-developed legs.

Hard Fescue (Festuca longifolia)

Hard fescue is a cool-season grass often used in cool-season grass seed mixtures when shade is an expected problem. It does well on low fertility soils and in shaded areas. This species is good as a non-mowed turf for slopes, median strips, and non-used areas of parks. It does not recover well from severe injury. It is not tolerant of high summer temperatures.

Heavy Soil

A soil that contains a high proportion of clay and is poorly drained.


A hectare (ha) is a metric unit of square measure, equal to 100 ares or 10,000 square meters, or 2.471 acres.


A chemical agent used in weed control.

Herbicide, Post-Emergent (POST)

Herbicide that needs to be applied after weeds emerge in order to be effective.

Herbicide, Pre-Emergent (PRE)

Herbicide that needs to be applied prior to weed emergence in order to be effective.

High Maintenance Lawn

Lawn areas composed of turfgrass species and varieties requiring higher levels of water, fertilizing and mowing to remain healthy.


Organic substance consisting of partially or wholly decayed vegetable or animal matter that provides nutrients for plants and increases soil’s ability to retain water.


The offspring of genetically dissimilar parents produced by breeding plants of different varieties, or species.

Infiltration Rate

The rate at which water is absorbed into the soil. Clay soils have low infiltration rates; sandy soils have high infiltration rates.

Inorganic (fertilizer)

Non-organic products used for supplying nutrients to a lawn that are immediately available for plant use following post-application watering.


A classification of arthropod with three pairs of legs and three body segments. Insects also have antenna and external mouthparts. (See Arthropod)


A pesticide used to kill insects.

Integrated Pest Management (IPM)

An ecosystem-based strategy of controlling pests or their damage. Steps include observing pest life cycles, monitoring pest activity and establishing guidelines defining action levels where the degree of damage becomes unacceptable. Action begins with the least invasive techniques such as modifications of cultural practices and adaptations of habitat. Pest control materials are used only as warranted with the selection and application method based on the least possible hazard to humans, non-target organisms and the environment.

Invasive Plants

An invasive plant has the ability to thrive and spread aggressively outside its natural range. An invasive species that colonizes a new area may gain an ecological edge since the insects, diseases, and foraging animals that naturally keep its growth in check in its native range are not present in its new habitat.

Japanese Beetles

An insect that eats foliage in its adult stage and grass roots in its laval stage. The larvae are called grubs and can cause widespread damage to turf.

Kentucky Bluegrass (Poa pratensis)

A common cool-season grass popular in the central United States having slender, green to dark green leaves. It spreads by rhizomes creating a dense, tight-knit sod.

Kikuyugrass (Pennisetum clandestinum)

Kikuyugrass is a warm-season grass that spreads quickly and thrives in areas with moderate temperatures. It can tolerate heat and will do well under relatively shady conditions.

Kyllinga (Kyllinga brevifolia)

A grass-like plant, in the sedge family, that grows in moist areas and is the target of weed control programs. In turf this weed makes for weak sod.


A brief description, warning and/or directions often found on pest control products or fertilizers.


A stage in the development of certain insects.


That portion of a yard or land area covered with mowed grass plants.


The downward movement in water of pesticides and/or nutrients through the soil.

Leaf Spot

A phase of a lawn disease in which grass is marked with spots that look like small burns.


A substance, produced by heating limestone, used in lawn care to adjust low (acidic) pH levels to encourage healthy grass.

Liquid Fertilization

A method of applying liquid plant nutrients.


Fertile soil, usually an organic mixture of clay, sand and decaying material that creates a rich soil for growing grass.

Low Toxicity

Term which the Environmental Protection Agency (EPA) uses for pesticides that have low toxic levels. Toxicity is the degree of damage a substance causes to an organism.

Low Maintenance Lawn

Lawn areas that require less water, fertilizer and mowing.


An important part of the soil ecosystem. Microbes include algae, fungi, protozoa, bacteria and other crucial substances for a healthy lawn.


The nutrients required in minute amounts for healthy grass. They are: iron, manganese, zinc, copper, molybdenum, boron and chlorine. Micronutrients often are supplied to plants growing in mineral soils, but supplemental applications may be needed for grasses in high pH or sandy soils.


Living organisms that help break down organic material through decomposition to create rich soil.

Mixture, Seed

A grass seed mix is a combination of two or more species of grass, such as Kentucky bluegrass and perennial ryegrass. It may contain multiple subspecies (also called varieties or cultivars) of each species with the variety selection tailored to the strengths and weaknesses of a lawn. The mix can be formulated to grow grass better in shady or sunny areas. A lawn of mixed species and varieties can also help prevent damage from some lawn diseases.


Fine green plants that have threadlike stems with very small leaves and tend to grow in grassless patches of lawns. Moss grows in soil that isn't conducive to producing healthy grass.


The periodic cutting of lawn grasses to a specified height.


Non-living material used to cover the soil for the purpose of controlling weeds, conserving moisture, reducing soil temperatures, or improving appearance. Examples include bark, wood chips, compost, etc.

Mulching Mower

Mowers specifically designed to finely chop grass clippings and recycle them to the lawn to return nutrients.


A fungi’s above ground spore-producing structure having an umbrella-like cap on a stalk.

Native Grass

Grass species indigenous to an area that was not introduced from another area.

Necrotic Ring Spot

Associated with summer patch disease, necrotic ring spot is a turf disease that affects many types of growing grasses. Symptoms include small, light green patches that grow and turn reddish brown in color, appearing in streaks and circular patterns around a center of relatively healthy green grass. Caused by root-infecting fungi.


A pesticide used to kill nematodes.


A microscopic, worm-like organism that feeds on the roots of all plants, including turfgrasses. Nematodes cause roots to be stunted and clubbed, rot, die back, and have little branching.


Abbreviations expressed as numbers on a fertilizer label for the primary nutrients necessary for plant growth – nitrogen (N), phosphorus (P), and potassium (K). Example: 5-10-15.


Nitrogen is the most important element in turfgrass used for photosynthesis. Nitrogen rich fertilizers are often used to enhance and maintain turf appearance (green color) and density.

Nitrogen – Slow Release

Slow release sources of nitrogen include organic materials broken down over time by soil microorganisms and synthetic forms of nitrogen either coated or in a complex formulation designed to slow the nitrogen release. These materials produce slow turf green-up, have a long residual, and low burn potential.

Nitrogen – Quick Release

Quick release nitrogen is water-soluble and produces fast greening of turf. Quick release nitrogen sources have a short residual and high burn potential.


An enlarged joint on grasses where leaves, roots, branches, or stems develop.

Non-selective Herbicide

Herbicide that kills or injures all plants.

Nutrient Release Rate

The speed at which plant nutrients such as nitrogen (N) become available for plant use following application on a lawn.


Mineral elements considered essential for plant growth.

Nutsedge (Cyperus sp.)

A member of the sedge family, an aggressive grass-like weed commonly found in lawns, vegetable and flower gardens.


A stage in the development of certain insects where the young resemble the adult in form, eat the same food, and reside in the same environment. Unlike typical larva, a nymph’s form already resembles that of an adult. Chinch nymphs for example can kill lawns by removing vital nutrients from grass blades causing the blade to turn brown and die.


A general term used for a type of gardening using no chemical or synthetic fertilizers or pesticides.

Organic Fertilizer

Animal or plant products such as manures, bone meal, seaweed, alfalfa meal, compost or other plant or animal byproducts that are used for fertilizer for garden or lawn care. Organic fertilizers are slow release fertilizers, meaning they are decomposed by soil microorganisms to release nutrients gradually. They are an alternative to synthetic fertilizers.

Organic Lawn Care

Organic lawn care is the practice of maintaining a healthy lawn without the use of chemical or synthetic herbicides, pesticides, or fertilizers. Some methods of organic lawn care include mowing high, leaving grass clippings on the lawn and watering less frequently as well as using organic fertilizers and pesticides.

Organic Matter

Organic matter is a naturally occurring material such as manure, peat, grass clippings, etc. that is used as a soil amendment. Some materials, such as sewage sludge, may be processed into a form that is easier to handle and apply than the raw material.

Organic Soil

Organic soil only contains ingredients that have been classified as organic as opposed to commercially produced soil that includes high levels of chemical fertilizers and pesticides.


Ornamental plants or grasses are typically used in landscapes for decoration and often require low maintenance.


The practice of putting more seeds on a lawn to improve its density.

Parts Per Million (PPM)

A way of expressing diluted concentrations of substances. Usually describes the concentration of something in water or soil by weight or volume. One ppm is equivalent to 1 milligram of something per liter of water or 1 milligram of something per kilogram soil.

Paspalum (Paspalum sp.)

Paspalums are a group of Paspalum species and subspecies of warm-season turfgrasses that grow in tropical areas throughout the world. Paspalum is also referred to as Seashore Paspalum, Siltgrass, Sheathed Paspalum, Salt Jointgrass, Seaside Millet, Sand Knotgrass, and Saltwater Couch.


When referring to diseased turf, localized areas that are irregularly shaped and greater than 4 inches in diameter.

Pathogen (plant)

Usually applies to a microorganism with the capacity to cause a plant disease.


Peat is partly decomposed plant material found in marshy areas used as fertilizer and fuel.

Perennial Plant

Perennials are plants that last three years or more as opposed to "annual plants" (one year) or "biennials" (two years). Types of perennials include woody plants such as trees and shrubs as well as small flowering plants and grasses.

Perennial Bentgrass (Agrostis palustris)

Perennial or Creeping bentgrass can occur in most lawns throughout growing season, especially in moist, fertile areas where the turf is closely mowed.

Perennial Ryegrass (Lolium perenne)

Perennial ryegrass is a cool-season bunchgrass that can tolerate high traffic. It can be identified by its fine texture and a bunchgrass-type growth habit.


Any organism considered harmful to a living plant. Major types of pests include diseases (fungi), insects, nematodes and weeds. Other turfgrass pests include moles, voles, millipedes, mites, earthworms, etc.


Any chemical (or mixture of chemicals) or biological agent used to control plant or animal pests. Pesticides include fungicides, herbicides, insecticides, and nematicides. (See fungicide, herbicide, insecticide and nematicide.)

PGR (Plant Growth Regulator)

Plant growth regulators (PGRs) are chemicals which control some aspect of plant growth or development.

pH level (soil)

Indicates the acidity or alkalinity of the soil. The pH scale reads from 0 to 14. 0 indicates extreme acidic soil and 14 extreme alkaline soil. A pH of 7 is neutral (neither acidic or alkaline).

Phloem (see xylem)

The phloem and the xylem are the two types of transport tissues in vascular plants. The phloem transports food and nutrients, such as sugar and amino acids, with bidirectional movement (up and down) throughout the plant. The xylem transports water and minerals upwards, from the roots to the aerial portions of the plant.


One of the major plant nutrients; important in root growth and plant energy functions.


A process by which a plant produces its food using energy from sunlight, carbon dioxide from the air and water from the soil.


Individual plants which are rooted pieces of sod and used for planting lawn areas. Grass plugs of sod, 2 to 3 inches wide are placed in equally spaced holes. The best varieties of most warm-season, spreading grasses are available only in vegetative form: sod, plugs, or sprigs.

Poa Annua

The scientific name given to annual bluegrass, a low-growing and cool-season grass which dies in early summer as the top layer of soil begins to dry. Poa annua (not to be confused with Kentucky bluegrass, Poa pratensis) is considered a winter-annual grassy weed that produces numerous seeds and spreads easily.

Pore Space

Spaces within soil that contain air and water allowing for the expansion of fibrous roots. Sandy soils contain the most pore space whereas clay soils contain the least.


One of the major plant nutrients important in maintaining general plant health, associated with improved stress and disease tolerance.

Power Raking

Power raking involves using fixed knife-type blades that slice thatch removing dead debris that can build up on a lawn.

Power Seeding

A method of applying seed that involves turning up or penetrating into the soil to achieve proper seed to soil contact.


Pounds per square inch.

Pythium Blight

Pythium blight is one of the most destructive turfgrass diseases. It first appears as small, sunken, circular patches up to 1 foot in diameter during hot, humid weather. Leaves within the patches are matted, orange or dark gray in color, and greasy in appearance. Gray, cottony mycelium may be seen in the infected areas when the leaves are wet or humidity is high. This disease can spread rapidly and cause severe damage to a turfgrass.

Reclaimed Water

Reclaimed water or recycled water can be treated wastewater, treated sewage or water from ordinary domestic water use that does not involve the toilet (Gray Water). Reclaimed water can also refer to rain water that has been recovered and stored. The reclaimed water can be reused for various non-drinking purposes, such as irrigation of lawns and other plants.

Red Fescue (Festuca rubra)

Red fescue is a cool-season grass used in cool, shaded, mountain sites, such as camps, resorts, and cabins where low-input of mowing, fertilization, and irrigation is desired. It does not do well in hot climates, except in shady, dry situations. In areas where Kentucky bluegrass does well, red fescue forms an excellent companion grass to increase shade tolerance. Red fescue germinates and establishes slowly. It is moderately wear resistant.

Red Thread

A type of lawn disease that causes reddish or pink threads to appear throughout a lawn.

Registered Seed

A type of high quality, superior seed grown and distributed to ensure genetic purity and identity.


When the quality of a lawn is no longer acceptable, a lawn renovation may be required. Renovations can include planting additional seed into a lawn, or adding new grass varieties to repair damage and increase the tolerance of the lawn to shade, wear and tear, or drought.


Replanting grass seed on a lawn that needs renovation, or has bare or thinning spots.


Left over residue on a lawn sometimes resulting from the use of herbicides or insecticides.


An underground creeping stem which can produce roots and shoots at each node.


Circular areas of diseased turf with healthy turf to the inside and outside, leaving a ring-like pattern.


After new sod is placed, the turf is irrigated until fully saturated, then a weighted lawn roller is moved back and forth across the graded lawn to smooth out the seams.


Part of the grass plant that typically grows below the surface of the soil and is associated with mineral and water absorption.

Root Hair

Tiny hair-like growths that occur on the surface of plant roots.

Root Zone

That portion of the soil column occupied by plant roots.


A motorized rotary cultivator with spinning blades perpendicular to the ground. Used to break up, mix and amend soils as part of the preparation of soil for plant beds and lawns.

Rough Bluegrass (Poa trivialis)

Rough bluegrass is best adapted to wet, cool, and shady areas. A cool-season grass, it is sometimes used for shaded turf in the fog belt areas and can be used to overseed dormant bermudagrass. Because of its light green color, it may be considered a weed in some lawns where it appears in patches within the preferred darker colored grass.


An orange or yellowish powder or spores that appear on blades of grass. Rust usually happens when weather conditions are dry.

Ryegrass (Lolium sp.)

Ryegrasses are a group of Lolium species and subspecies that are the most widely grown cool-season grasses in the world. Due to its versatility and rapid growth rate, ryegrass is ideal for lawn and pasture purposes in cooler temperatures.

Saline Soil

A soil containing enough soluble salt to negatively affect plant growth. This soil condition can be caused by both natural and artificial means, and is often the result of inadequate drainage, which prevents saline from being leached.


A fine gritty or grainy material that can be used as a filler if soil is too soft and needs to be firmed up, or if the composition of the soil is less than desirable.


A fungal disease found in grass and some fruit trees. The most common and damaging form, fusarium head blight, causes scabs or lesions on golf course grass.


A brown, stubbly appearance that can appear on lawns as a result of extremely close mowing. Scalping can result in weaker grass that is more susceptible to weeds and the development of brown patches.


A condition affecting grass that has been exposed to excessive heat from the sun, extended drought periods or improper use of pesticides and lawn fertilizers. Symptoms of scorch include dry, brittle and brown patches of grass.

Seashore Paspalum (Paspalum vaginatum)

Seashore Paspalum is a very salt tolerant warm-season grass with desirable turfgrass characteristics. This specialty grass is sometimes used in warm-season areas where either the soil or irrigation water has a high salt content. It does well near the ocean where it is subject to saltwater. Improved cultivars have been developed.

Seed Blend

A blend of grass seeds containing only one species of grass, but multiple subspecies (also called varieties or cultivars). Seed blends are highly adaptable, provide different germination speeds and the variety selection can be tailored to the strengths and weaknesses of a lawn. The blend can be formulated to grow grass better in shady or sunny areas. Blended lawns can also help prevent damage from some lawn diseases.

Seed Mixture

A grass seed mix is a combination of two or more species such as Kentucky bluegrass and perennial ryegrass. It may contain multiple subspecies (also called varieties or cultivars) of each species with the variety selection tailored to the strengths and weaknesses of a lawn. The mix can be formulated to grow grass better in shady or sunny areas. A lawn of mixed species and cultivars can also help prevent damage from some lawn diseases.

Seed, Certified

A seed lot inspected to meet minimum standards for a given cultivar.

Selective Herbicide

A specific type of herbicide that targets weeds but does not harm the turfgrass that may surround them.

Semiarid Turfgrass

Turfgrasses adapted to grow in semiarid regions without irrigation, such as buffalograss, gramagrass, and wheatgrasses.


The new growth of a plant. In growing grass, the shoot comes from a germinated seed.

Shoot Density

The number of shoots contained in a specified area of lawn.


Soil particles that are larger than clay and smaller than sand.


Penetration of turf in a vertical plane by a series of solid flat tines.


The use of a machine known as a slit-seeder to seed a new lawn area or overseed an existing area. Slit-seeders utilize a series of vertically rotating blades to cut small grooves into the soil for improved seed-to-soil contact.

Slow-Release Fertilizer

A material that adds nitrates to soil at a slower pace to sustain nutrients for a longer period of time.


A group of parasitic fungi grass diseases that resemble a yeast-like buildup on grass and leaves. Stripe smut and flag smut are two common smuts found on Kentucky bluegrass. While most smuts complete their lifecycle on one plant, they can begin in the ground and readily attack seedlings planted in infected soil.

Snow Mold

A family of fungi that forms circular, dead patches of grass visible after the snow melts.


Squares or strips (rolls) of turfgrass cut from a turfgrass production field, usually with a thin layer of soil still attached, that is used for vegetatively installing a turfgrass area.

Sod Webworm

A species of moth larvae that feed on most turfgrass, but tend to prefer Kentucky bluegrass, perennial ryegrass and fine fescues. Damage usually begins with change in climate but is more extensive in the warmer months.


A material made up of rocks and minerals, organic matter, and water. Soil makes up the top layer of the surface of the earth.

Soil Amendment

Any material added to the soil to improve its quality.

Soil Compaction

Soils that are subject to heavy traffic are prone to compaction and can cause reduced drainage, increased runoff and inhibit root growth. Aeration can help alleviate compaction.

Soil Erosion

Soil erosion is the removal of soil particles and organic matter as a result of either water or wind.

Soil Test

A measurement of pH and nutrients in the soil.

Soluble (fertilizer)

Fertilizers that are made up of components easily dissolved in water which are immediately available for plant use. They can result in lawn "burning" more easily than slow-release fertilizers.


In biology, species can best be defined as a group of living organisms consisting of similar individuals capable of exchanging genes or interbreeding. Samples of turfgrass species include: Fescues, Bluegrass, Ryegrass, Bentgrass, Bermuda, Zoysia, etc.


A stolon or rhizome used to establish a turf.

St. Augustine Grass (Stenotaphrum secundatum)

A common lawn grass found in southern portions of the United States. Prefers dryer, non-compacted soil conditions. In areas where it is well adapted, it is water efficient and has few pest problems. It prefers full sun, but has a high tolerance for shade. It grows quickly during the summer months, but slows growth during the spring and fall and enters a dormancy period in the late autumn and during the winter months. Because St. Augustine Grass is not wear tolerant, it is used for lawns and general purpose turf, but not for high traffic sports turf.


An above-ground creeping stem that can produce roots and shoots at each node.


A condition that can restrict normal or healthy plant growth such as heat, drought, compacted soil, traffic, etc.


An abundant tasteless, odorless, multivalent, nonmetallic element; best known in yellow crystals. It occurs in many sulphide and sulphate minerals and even in native form (especially in volcanic regions). Elemental sulfur is often used to lower the pH of an alkaline soil.

Summer Patch

Lawn disease that appears as green growth in the middle of dead brown patches

Sustainable Lawn Care

A form of lawn care that is beneficial to a lawn and the environment. Sustainable lawn care may include water conservation practices, utilizing more natural fertilizers, striving to save energy and resources such as recycling grass clippings.


The visual characteristics associated with a lawn problem such as disease, insect activity, compaction, nutrient deficiency, etc.


Systemic insecticides are those in which the active ingredient is taken up, primarily by a plant’s roots, and transported to locations throughout the plant, such as growing points, where it can affect pests.

Tall Fescue (Festuca arundinacea)

A cool-season grass, well adapted to sunny or partially shady areas. When densely sown, a pure stand forms a moderate to coarse-textured lawn that is uniform in appearance with good weed and disease resistance. Tall fescue tolerates warm summer temperatures and stays green during cool, but not severe, winter conditions. New varieties that are finer in texture and shorter in stature are known as turf-type tall fescues and dwarf turf-type tall fescues. Tall fescue is a good species to plant for general lawn use and is the most common lawn grass in California.


A dense, fibrous layer of living and dead grass stems, leaves, and roots, undecomposed or partially decomposed, that accumulates between the green vegetation and soil surface. A thin layer of thatch is helpful because it can limit weed growth and protect some grasses from early frosts. But too much thatch (over ½ inch thick) can encourage insect infestation and some lawn diseases.

Top Dressing

A sand or prepared soil mix applied to the turf to help smooth the surface and/or enhance its establishment.


A type of local systemic activity, where the translaminar pesticide penetrates into the leaf and moves through the leaf tissue to protect the untreated side of the leaf, thus when sprayed on the top surface of a leaf the underside will also be protected.


The upper portion of soil that is generally high in organic matter and has favorable characteristics such as greater soil fertility and provides better aeration than subsoils.


A term used to define a material’s hazard potential.


A covering of mowed vegetation, usually a grass.

Turf Tolerance

The ability of a species of turf to withstand the application of a pesticide (herbicide, fungicide, insecticide, etc.) at the normal dosage without being killed or injured.


A species or cultivar of grass which is maintained as a mowed turf. Includes all common warm- and cool-season grasses.


Being a variety in distinction from an individual or species.

Velvet Bentgrass (Agrostis canina)

A warm-season fine-textured, high-density forming turfgrass ideal for golf course putting greens. It has the finest texture of all the bent grasses and is one of the oldest grasses used for lawns and golf courses in Europe. It was brought to the US for use on the earlier putting greens because of its texture and ability to be clipped closely.

Warm-Season Turfgrass

A type of grass suited for warm arid and humid climates that typically thrives in the southern United States. A warm-season turfgrass has its optimum growth at temperatures between 80° and 95°F (27° to 32°C). Warm-season grasses include bahiagrass, bermudagrass, carpetgrass, centipedegrass, St. Augustine and zoysiagrass.


Any invasive, difficult or unattractive plant that grows in an area where it is not wanted.

Wetting Agent

A chemical that aids in liquid-to-surface contact.

Winter Fertilization

Application of fertilizer that is made after the turf is dormant and has lost its color for the season. Winter fertilization encourages root growth needed for turf health and density.


To create a low maintenance landscape using native plants and small or non-existent areas of turfgrass. One of the goals of xeriscaping is to reduce water use.

Xylem (see phloem)

The xylem and the phloem are the two types of transport tissues in vascular plants. The xylem transports water and minerals upwards, from the roots to the aerial portions of the plant. The phloem transports food and nutrients, such as sugar and amino acids, with bidirectional movement (up and down) throughout the plant. The xylem is a tissue of higher plants that also functions in support and storage, it lies deeper inside the plant than the phloem, and usually makes up the woody parts (as of a plant stem).

Zoysia grass (Zoysia japonica)

Zoysia grasses are sod-forming perennial species that possess both stolons and rhizomes. The grasses turn brown after the first hard frost and are among the firt warm-season grasses to green up in the spring. Zoysia grass is a popular creeping lawn grass that adds versatility and texture to yards or landscapes.

This information provided by The Lawn Institute – www.TheLawnInstitute.org

Back to Home or Top

loaded in 15.6249ms | 1/15/2021 1:53:19 PM