Kentucky bluegrass (Poa pratensis L.)Canada bluegrass (Poa compressa L.)Rough bluegrass (Poa trivialis L.)Annual bluegrass (Poa annua L.)Supina bluegrass (Poa sup inaSchreb.)

Italian ryegrass (Lolium multiflorumLam.)Perennial ryegrass (Lolium perenneL.)

The 20th in a series by

R.W. Sheard, P.Ag.

margins of the leaves overlapping (Fig.1).

The leaf blade may be used in identify-ing species on the basis of the shape of theleaf tip. The differentiating characteristicis whether the leaf tip is boat shaped orpointed apex (Fig. 2).

The leaf sheath is that tubular part ofthe leaf, arising at the node and closelyclasping the stem or younger. growingleaves upward to where the blade begins.The leaf sheath may be classified as splitfrom the node to emergence of the blade,split at the top but tube-like near thenode, or closed the entire distance fromthe node to where the blade emerges (Fig3).

The collar is a meristematic band orgrowth zone which marks the divisionbetween the blade and the sheath. Thecollar may be broad and prominent ornarrow, continuous from one margin ofthe leaf to the other, or divided by aconspicuous midrib. In some species itmay be higher on one side of the leaf thanthe other (Fig 4).

The auricles are appendages projectingfrom the collar, one from either side.They may be absent or vary in length andshape from long and claw-like to smalland rounded or rudimentary (Fig. 5)

The ligule is a tongue-like outgrowth atthe junction of the blade and the sheathclasping the culm or bud shoot. It mayappear as a fringe of hair or as membra-nous tissue, or may be pubescent [cov-ered with soft hairs] on the back (Fig. 6).

There are over 7,500 species which be-long to the family of plants calledGramineae. As turf grass managers in thecool temperate region, however, we needto be concerned with only 16 of thesespecies. They have been discussed in re-cent articles in this series and for revieware listed again.

UNDERSTANDING TURF MANAGEMENT

Species Identification

Tall fescue (Festuca arundinaceaeSchreb.)Meadow fescue (Festuca elatior L.)Creeping red fescue (Festuca rubraL.)Sheeps fescue (Festuca ovina L.)Hard fescue (Festuca ovina L. subsp.duriuscula)

Creeping bentgrass (Agrostis stolonif-era Huds.)Colonial bentgrass (Agrostis tenuisSibth.)Velvet bentgrass (Agrostis canina L.)Redtop (Agrostis alba L.)

To this list we must add three foragegrasses which may invade a turf area andtwo weed grasses which create controlproblems. They are:

Brome grass (Bromus inermis L.)Timothy (Phleum pratense L.)Orchard grass (Dactylis glome rata L.)Twitch (quack) grass (Agropyron re-pens L.)Crabgrass (Digitaria ischaemumSchreb.)

To aid in separating the identifyingcharacteristics of each species and decid-ing on which species you are dealing withbotanists have developed an identifica-tion key. With the aid of a sharp knife anda small hand lens the plant is systemati-cally examined for the several charac-teristics listed above until a the name ofthe species is arrived at.

The management of turf often re-quires we know what species of grass

we are working with. The manager maywish to know whether his sports field isbluegrass, ryegrass or tall fescue. His re-cords may be misplaced as to what wasseeded originally and with time a mixtureof species may have become dominatedby one species. So what is it?

The answer is obtained through identi-fying certain vegetative plant parts; thenaccording to their characteristics decidewhat species you are working with. Theplant parts are the root system, the leafblade, the bud-shoot, the sheath, the col-lar, the auricle and the ligule.

The root system identification charac-teristic is based on the presence or ab-sence of stolons or rhizomes. An abilityto identify stolons from rhizomes is criti-cal for this step. Stolons are stems whichgrow along the soil surface or within thethatch layer. New roots and shootsemerge from the nodes on these stems.The stolons may branch at the nodesforming a network of stolons. Rhizomesare also stems, but they grow horizontallybelow the soil surface. When the stemapproaches the soil surface light responsestimulates the formation of shoots androots at a node on the stem and a newplant results from which one or morenew rhizomes may emerge.

Generally stolons and rhizomes aremuch larger in diameter than the fibrousroot system, therefore they should not beconfused with roots.

The bud shoot or bud leaf is the mannerin which the newly emerging leafemerges. The arrangement of the budshoot is the basic point from which allidentification of grasses commences. Thebud shoot may be folded with the mar-gins of the leaves meeting but not over-lapping or it may be rolled with the

AN IDENTIFICATION KEY FOR TURF SPECIES1.0. - Folded in the bud shoot.

1.1. - Au ricle present.1.1.1. - Lower leaf sheath reddish, back of leaf shiny.

1.2. - Auricle absent.1.2.1. - Ligule membranous.

1.2.1.1. - Blade narrow, prominently ridged on upper surface.1.2.1.1.1 . - Ligule less than 0.5 mm or absent, sheathsplit, leaves waxy, plant tufted.1.2.1.1.2. - Ligule over 0.5 mm, sheath closed, leavesnot waxy, plant not tufted.

1.2.2. - Ligule absent to very short.1.2.2.1. Without rhizomes.

1.2.2.1.1 . - Sheath keeled or with prominent ridge likea boat keel running down base of leaf which graduallytapers to apex.

1.2.2.2. - With rhizomes.1.2.2.2.1. - Sheath not keeled,leaf parallel sided, withabruptly pointed and boat shaped tip.

1.2.3. - Ligule rounded or pointed, more than 1.0 mm long.1.2.3.1. - With stolons.

1.2.3.1.1. - Tapered and boat shaped leaf tip, sheath rough,blade glossy under surface.

1.2.3.2. - Without stolons.1.2.3.2.1. - Parallel side leaf with tip abruptly pointedand boat shaped.1.2.3.2.2. - Leaf blade wide and taper pointed, stembase flattened.

Perennial ryegrass

Sheep fescue

Red fescue

Canada bluegrass

Kentucky bluegrass

Rough bluegrass

Annual bluegrass

Orchardgrass2.0. - Rolled in the bud shoot.

2.1. - Auricles present.2.1.1. - Auricle blunt to claw like and with minute marginal hairs, very shinyunderside, strongly ribbed upper side of leaf.2.1.2. - Auricles without marginal hairs, leaf soft and less shiny, margin ofleaf harsh or slightly rough or jagged to finger when slid lengthwise downedge near leaf base.2.1.3. - Margin of leaf smooth, auricle small, rarely reaching 1/4 distancearound stem, ligule over 1 mm.2.1.4. - Sheath, collar, and blade with short soft hairs, rhizomes prominentwhich are white and pointed.

2.2. - Auricles absent.2.2.1. - Ligule membranous.

2.2.1.1. - Leaf sheath closed, its margins united except for a smallV-shaped notch near the collar, leaf sheath and blade hairless, "W'''marking of wrinkled tissue near middle of leaf, rhizomes present.2.2.1.2. - Leaf sheath split, hairless and compressed with ridgeor keel down the back.

2.2.2. - Ligule 1.5 mm or longer with prominent notch on either side, enlargedor bulbous base to stem.

2.2.2.1. - Ligule without notch, rhizomes present.2.2.2.2. - Ligule shorter than 1.5 mm, rhizomes slender and short.2.2.2.3. - Stolons present.2.2.2.4. - Stolons present, ligule tends to be pointed.

Tall fescue

Meadow fescue

Italian ryegrass

Quack grass

Bromegrass

Crabgrass

TimothyRedtopColonial bentgrassCreeping bentgrassVelvet bentgrass

key reveals that the plant you have exam-ined is Kentucky bluegrass.

Practice is necessary to develop skills inusing the key. Some initial short cuts canoften save time, such as to examine theplant for rhizomes or stolons. Broad leafspecies will often turn out to be quackgrass or forage grasses. Crab grass inAugust can easily be identified by its par-ticular seed head, even under two inchmowing.

It is important to remember that the keyis based on contrasting pairs of state-ments. If the first statement is not truethen you move on to the next statementat the same level in the key.

Let us take an example. The first char-acteristic listed in the key is the budshoot. As there are only two possibilitiesthe first step is to determine whether thesample is folded in the bud shoot orrolled in the bud shoot. Let us assumethat it is folded (1.0). The alternative

statement IS rolled in the bud shoot(2.0.). The second step is to determinewhether the sample has auricles. Let usassume that it does not (1.2.). The thirdstep is to examine the shape of the ligule.Let us assume that ligule are hard to seeor absent (1.2.2). Further examinationreveals the plants have very prominentrhizomes (1.2.2.2.) and for confirmationthat the leaves are not tapered but paral-lel sided and boat shaped at the tip. Fol-lowing these observations through the

ILLUSTRATIONS OF VEGETATIVE CHARACTERISTICS USED FOR GRASS IDENTIFICATION

A B

FIGURE 1: The Bud Shoot (A = folded, B = rolled)

A B cFIGURE 3: The Leaf Sheath (A = split, B = split

with margins overlapping, C = closed)

Side Top' VIEW • Top SideA B

c~ ----~.

o~

~

FIGURE 2: The Leaf Tip and Surface(A = tapered, B = boat-shaped, C= ridged but not keeled, D = not ridged and keeled)

A B c E Fo

FIGURE 4: The Collar (A = broad band, B = narrow band, C = divided by midrib,D = Oblique, E = Pubescent, F = ciliate, note: A - E are back views, F is a front view)

AA B c o

FIGURE 5: The Auricle (A = claw like, B = rounded, C =rudimentary, D = absent)

B cFIGURE 6a: The Ligule Types, (A = fringe of

hair, B = membranous, C = absent

A BB c DA

FIGURE 6b: The Ligule Margin (A = entire, B = notched, C= lacerate, D = ciliate)

c D

FIGURE 6c: The Ligule Shapes (A = acute, B = rounded, C= truncate, D = marginate)

Sports Turf Manager - 5