Turf Bowl 2026 Packet

What are the two properties accounting for soil reactivity?

Surface area and surface charge.

What colloids are responsible for soils' chemical reactivity?

Clay and organic matter colloids.

What three chemicals are relatively abundant at CEC exchange sites?

Potassium, calcium, and magnesium.

True or False: Cation exchange is a reversible process.

True.

What pH needs to be maintained to increase CEC values in sandy soils?

5.5 to 6.5.

In most basins, what pH must be exceeded to achieve 100% base saturation?

7.0.

What is the process of cations dispersing rather than attracting clay particles?

Dispersion or deflocculation.

Soils containing clay or organic matter have a higher or lower lime index?

Lower.

What acids are 'strong' because they dissociate completely?

Hydrochloric, sulfuric, and nitric acids.

How is acid neutralization achieved in turf?

Using lime as the base.

What is the pH range for optimum turf growth?

6.5 to 6.6.

Thatch accumulation and algae problems can be associated with what?

Low soil pH (

Why is ground limestone difficult to spread?

It is dusty in pelletized form.

How is limestone often obtained?

Open-pit mining.

Why is liquid lime only applied in small amounts at one time?

Potential plant phytotoxicity.

How often should soil pH be monitored in established turf?

Annually.

What should be considered when choosing a liming material?

Degree of fineness, neutralizing value, Mg content, plant-tissue burn potential, and moisture content.

What material is most often injected into irrigation systems to raise the pH of irrigation water?

Powdered carbonate.

What is a possible result of excessive soil alkalinity?

Deficiencies of several micronutrients necessary for plant growth.

What effect does micronutrient deficiency have on turf?

Turf will be yellow and chlorotic.

True or False: Elemental sulfur, in its pure form, is insoluble and therefore cannot be applied alone with irrigation water.

True.

What turf diseases are reduced as a result of sulfur?

Patch diseases and Poa annua levels.

A Horizon

Topmost mineral layer; where up to 80% of roots reside.

Active acidity

Activity of H ion in aqueous phase of soil; measured by pH.

Potential acidity

Amount of exchangeable H ions from soil sites.

Aerobic

Having molecular oxygen as part of environment.

Aggregate

Many soil particles held together in a single mass.

Air porosity

Proportion of soil volume filled with air at any time.

Alluvium / alluvial

Sand, soil, muck, etc., deposited by moving streams.

Anaerobic

Absence of molecular oxygen.

Anion

Ion carrying a negative electrical charge.

Available water

Portion of water in soil available for plant use.

Base-saturation %

Extent the exchangeable part of soil is saturated with base cations.

Bulk density

Mass of dry soil per unit volume.

Capillary water

Water held in the capillary or small soil pores.

Cation

Ion carrying a positive electrical charge.

Cation exchange capacity

Sum total of exchangeable cations that a soil can absorb.

Clay

Soil separate equal to 0.002 mm or smaller in diameter.

Colloid

Organic or clay particles equal to/smaller than 0.001 mm in diameter.

Colluvium

Gravity-deposited soil/rock.

Compaction

Compressing soil so that air space is minimized.

Edaphic

Pertaining to the soil.

Eluviation

Loss of material from one layer to another within the soil.

Fallow

Cropland left idle in order to restore productivity.

Field capacity

Percentage of water left in soil after gravity has drained; 2-3 days.

Gravitational water

Water that moves into, through, or out of soil due to gravity.

Ground water

Portion of water that is free to move under the influence of gravity.

Hue

Soil color variable.

Hydrologic cycle

Revolving cycle of water from precipitation to evaporation to condensation.

Abaxial

Located on the side away from the axis (lower side of leaf blade).

Apical meristem

Terminal growing point.

Apomixis

Formation of viable embryo without male and female gametes union.

Blade

Flattened portion of leaf located above sheath.

Blend

Combination of two or more cultivars of single turfgrass species.

Castings

Soil and plant remains excreted by earthworms deposited on turf surface.

CWIN

Cold water insoluble nitrogen.

CWSN

Cold water soluble nitrogen.

Coleoptile

Protective sheath of an embryonic shoot.

Crown

Highly compressed stem located at base of vegetative aerial shoot.

Culm

Flowering stem of a grass plant.

Cultivar

Assemblage of cultivated plants when reproduced retain their features.

Cultivation

Refers to working of the soil and/or thatch without destruction of turf.

Dicot

Plant having two cotyledons in the seed.

Evapotranspiration

Total loss of moisture through evaporation and transpiration.

Extraviginal

Shoot growth that occurs through an enclosing leaf sheath.

Floret

A grass flower enclosed by a lemma and palea.

Glumes

A pair of bracts usually present at base of a spikelet.

Grass

Any plant of the family Poaceae.

HWIN

Hot water insoluble nitrogen.

Inflorescence

The flowering portion of a shoot.

Internode

Portion of the stem between two successive nodes.

Intravaginal

Shoot growth that occurs within an enclosed leaf sheath.

Lamina

Leaf blade.

Lemma

Lowermost of the two bracts enclosing the flower of a grass floret.

Marcelling

Wavy or washboard pattern on the surface cutting plane of mowed turf.

Meristem

Undifferentiated tissue with cells capable of division at tip of stem.

Mixture

Combination of two or more species.

Monocot

Plant having one cotyledon in the seed.

Node

The joint of a stem.

Nursegrass

Grasses not expected to survive.

Ovule

An immature seed contained within the ovary.

Palea

Uppermost of the two bracts enclosing the flower of a grass floret.

Pedicel

Stalk of a single grass floret.

Phloem

Principal food-conducting elements of vascular plants.

Photoperiod

Period of a plant's daily exposure to light.

Phytomere

Basic unit of structure of the grass shoot.

Pistil

Female structures of a flower.

PLS

Pure live seed.

Radicle

Primary root of the grass embryo.

Rhizome

Underground elongated stem.

Scum

Layer of algae on soil surface of thinned turfs.

Seed

Ripened ovule.

Shoot density

Relative number of shoots per unit area.

Sprig

A stolon, rhizome, or tiller used to establish a turf by planting.

Stamen

Male organ of the flower.

Stand

Number of established individual shoots per unit area (see shoot density).

Stolon

Elongated stem that grows along surface of ground.

Turf

A covering of mowed vegetation.

Turfgrass

Covering of maintained, mowed grass vegetation.

UF

Urea formaldehyde; synthetic slowly available organic fertilizer.