ieedlng rate: it·' effect on diiea/e and weed...

10
I EEDlnG RATE: IT·' EffECT On DIIEA/E AnD WEED EnCROACHmEnT By A. Douglas Brede Di.fference in broadleaf weed encroachment. Turf on right of stake was seeded with Kentucky bluegrass at three pounds per 1,000 square feet. The area to the left was seeded at less than one pound. S eeding rate recommendations-the figures listed in most turfgrass text- books- have been developed over the years by "seat of the pants" observation by turfgrass experts and authors. Until the late 1970s, little was known as to why these rates were best. New research from several United States universities has shown that, under certain circumstances, deviations from these recommended rates are not only allowable, but oftentimes advisable. By knowing when to deviate from these rates, the educated turfgrass manager can make better deci- sions on a case-by-case basis of when and where to use higher or lower rates than are published. I began a study in 1976 at Pennsylvania State University to scientifically investigate the effects of the seeding rate on the matu- ration of a turf stand and development of weeds and diseases. Specifically, we wanted to answer several questions: How long are the effects of seed- ing rate felt on the turfgrass stand? Is seed- ing rate of a transitory nature, exerting effects on the stand during only the first six months? Can higher seeding rates be used to effectively compete against annual bluegrass? Do certain cutting heights "prefer" certain seeding rates? And, What effect does turfgrass variety have on seed- ing rate? Kentucky bluegrass was chosen for this study. I evaluated the progress of this experi- ment for five years after planting. On regu- lar intervals we sampled the shoot density of the plots. We found that even 41 months after planting (nearly four years later), we were able to detect statistically significant differences among the four seeding rates in shoot density. It wasn't until nearly five years after the trial was established that we were no longer able to detect seeding rate effects on shoot density. We also found that it is desirable to use higher seeding rates with lower cutting heights. This is because lower cutting heights require more plants per square foot to maintain 100 percent ground cover than does a higher cut stand. The one pound of bluegrass seed per thousand square feet listed in many older turfgrass textbooks may have been appropriate when we were mowing Ken- tucky bluegrass at three inches height. Our research indicated that seeding rate should be doubled for every halving of the cutting height. For instance, while one pound might be acceptable for a three-inch cut, a two- pound rate might be better for an inch and a half, and a four-pound rate for a three- quarter-inch intended mowing height. This provides the desired shoot density of the stand without the usual "equilibration" peroid. The effect of Kentucky bluegrass seeding rate on encroachment of annual bluegrass is quite profound. Using a low seeding rate or a weak cultivar will "open the door" for invasion of annual bluegrass. This invasion can occur simultaneously with emergence of the Kentucky bluegrass or may happen within the first six months or a year after planting, due to a thin stand. Any time we do not have complete ground coverage of a turf stand, annual bluegrass being an opportunistic weed can take over. Seeding rates of three to four pounds of Kentucky bluegrass per 1,000 square feet were desirable where annual bluegrass seed was prevalent in the soil. Vigorous cul- tivars were also more desirable for use in competing with annual bluegrass. But you can get too much of a good thing. Going too far on the other extreme (seeding too heavily) may bring about added disease problems. We found that incidence of leafspot and Fusarium blight complex was directly related to seeding rate. Seeding rates above 3.5 pounds Ken- tucky bluegrass seed per thousand square feet increased the risk of disease during the establishment phase. Once a dense stand was hit with disease, however, the shoot density was lowered by the disease, and the stand subsequently had fewer disease problems. Where we prolonged the high-shoot den- sity by means of fungicides, the stand was at a greater risk of disease damage during times when fungicides were skipped or withheld. Ideal rates for seeding Kentucky bluegrass are two to three pounds of seed per thousand square feet. One pound or less would be considered too light, and greater than five pounds, excessive. Peren- nial ryegrass is best used at four to eight pounds per thousand square feet, with two pounds or less being too light, and greater than ten being excessive (except for over- seeding). Tall fescue benefits from a stouter seed- ing rate of six to ten pounds of seed per thousand square feet. Skimping on tall fes- cue seed is undesirable since tall fescue has no runners. Seeding at less than six pounds per thousand square feet is consi- dered too light, whereas seeding at greater than 15 pounds of seed per thousand square feet would be excessive. Editor's Note: A. Douglas Brede, Ph.D. is a research director. This article is an excerpt from a paper presented at the 1988 annual meeting of the Northwest Turfgrass Associ- ation in Spokane, WA. February, 1989 51

Upload: others

Post on 15-Aug-2020

0 views

Category:

Documents


0 download

TRANSCRIPT

Page 1: IEEDlnG RATE: IT·' EffECT On DIIEA/E AnD WEED EnCROACHmEnTsturf.lib.msu.edu/page/1989feb51-60.pdf · 2009-06-04 · IEEDlnG RATE: IT·' EffECT On DIIEA/E AnD WEED EnCROACHmEnT By

IEEDlnG RATE:IT·' EffECT On DIIEA/E AnDWEED EnCROACHmEnT By A. Douglas Brede

Di.fference in broadleaf weed encroachment. Turf on right of stake was seeded with Kentuckybluegrass at three pounds per 1,000 square feet. The area to the left was seeded at less thanone pound.

Seeding rate recommendations-thefigures listed in most turfgrass text-books- have been developed over

the years by "seat of the pants" observationby turfgrass experts and authors. Until thelate 1970s, little was known as to why theserates were best.New research from several United States

universities has shown that, under certaincircumstances, deviations from theserecommended rates are not only allowable,but oftentimes advisable. By knowing whento deviate from these rates, the educatedturfgrass manager can make better deci-sions on a case-by-case basis of when andwhere to use higher or lower rates than arepublished.I began a study in 1976 at Pennsylvania

State University to scientifically investigatethe effects of the seeding rate on the matu-ration of a turf stand and development ofweeds and diseases.Specifically, we wanted to answer several

questions: How long are the effects of seed-ing rate felt on the turfgrass stand? Is seed-ing rate of a transitory nature, exertingeffects on the stand during only the first sixmonths? Can higher seeding rates be usedto effectively compete against annualbluegrass? Do certain cutting heights

"prefer" certain seeding rates? And, Whateffect does turfgrass variety have on seed-ing rate? Kentucky bluegrass was chosenfor this study.I evaluated the progress of this experi-

ment for five years after planting. On regu-lar intervals we sampled the shoot densityof the plots. We found that even 41 monthsafter planting (nearly four years later), wewere able to detect statistically significantdifferences among the four seeding rates inshoot density. It wasn't until nearly fiveyears after the trial was established that wewere no longer able to detect seeding rateeffects on shoot density.We also found that it is desirable to use

higher seeding rates with lower cuttingheights. This is because lower cuttingheights require more plants per square footto maintain 100 percent ground cover thandoes a higher cut stand.The one pound of bluegrass seed per

thousand square feet listed in many olderturfgrass textbooks may have beenappropriate when we were mowing Ken-tucky bluegrass at three inches height. Ourresearch indicated that seeding rate shouldbe doubled for every halving of the cuttingheight.For instance, while one pound might be

acceptable for a three-inch cut, a two-pound rate might be better for an inch anda half, and a four-pound rate for a three-quarter-inch intended mowing height. Thisprovides the desired shoot density of thestand without the usual "equilibration"peroid.The effect of Kentucky bluegrass seeding

rate on encroachment of annual bluegrassis quite profound. Using a low seeding rateor a weak cultivar will "open the door" forinvasion of annual bluegrass. This invasioncan occur simultaneously with emergenceof the Kentucky bluegrass or may happenwithin the first six months or a year afterplanting, due to a thin stand. Any time wedo not have complete ground coverage of aturf stand, annual bluegrass being anopportunistic weed can take over.Seeding rates of three to four pounds of

Kentucky bluegrass per 1,000 square feetwere desirable where annual bluegrassseed was prevalent in the soil. Vigorous cul-tivars were also more desirable for use incompeting with annual bluegrass.But you can get too much of a good

thing. Going too far on the other extreme(seeding too heavily) may bring aboutadded disease problems. We found thatincidence of leafspot and Fusarium blightcomplex was directly related to seedingrate.Seeding rates above 3.5 pounds Ken-

tucky bluegrass seed per thousand squarefeet increased the risk of disease during theestablishment phase. Once a dense standwas hit with disease, however, the shootdensity was lowered by the disease, and thestand subsequently had fewer diseaseproblems.Where we prolonged the high-shoot den-

sity by means of fungicides, the stand wasat a greater risk of disease damage duringtimes when fungicides were skipped orwithheld.Ideal rates for seeding Kentucky

bluegrass are two to three pounds of seedper thousand square feet. One pound orless would be considered too light, andgreater than five pounds, excessive. Peren-nial ryegrass is best used at four to eightpounds per thousand square feet, with twopounds or less being too light, and greaterthan ten being excessive (except for over-seeding).Tall fescue benefits from a stouter seed-

ing rate of six to ten pounds of seed perthousand square feet. Skimping on tall fes-cue seed is undesirable since tall fescuehas no runners. Seeding at less than sixpounds per thousand square feet is consi-dered too light, whereas seeding at greaterthan 15 pounds of seed per thousandsquare feet would be excessive.

Editor's Note: A. Douglas Brede, Ph.D. isa research director. This article is an excerptfrom a paper presented at the 1988 annualmeeting of the Northwest Turfgrass Associ-ation in Spokane, WA.

February, 1989 51

Page 2: IEEDlnG RATE: IT·' EffECT On DIIEA/E AnD WEED EnCROACHmEnTsturf.lib.msu.edu/page/1989feb51-60.pdf · 2009-06-04 · IEEDlnG RATE: IT·' EffECT On DIIEA/E AnD WEED EnCROACHmEnT By

From BucketLoader to

Versatile Fork Liftin less Than5 Minutes!

C.C. Bucket Forks can change a bucket-loader into a multi-purpose liftingvehicle. No drilling, welding or bolting.

Easy-on, easy-off installation-in less than 5 minutes.

Made in the U.S.A. Canadian Patent No. 1,103,622U.S. Patent No. 4,242,035

A NEW CONCEPT IN MATERIAL HANDLING!

CHECK THESE SPECIAL FEATURES!• Easy storage- tines are separate and flat• Transports easily- no awkward angles• Easy to handle-each fork weighs only50 pounds

• Universal-fits most popular brands ofloader buckets

• Easy-on, easy-off installation - in lessthan 5 minutes!

• Ideal for farm use or at constructionsites

• Handles most materials-load capacityis 3,000 pounds

• Full money back guarantee!

$399.00(delivered anywhere in U.S.)Send you r checkor money order to:cc~--.

CC. Bucket forks, Inc~P.o. Box 3796, Orange, CA 92665

In Calif. call collect:

1-714-637-4645Toll-free, except in Calif.

1-800-854-3532

CA RES. ADD 6% SALES TAXCopyright 1981 C.C. Buckst'Forks, Inc.Circle 215 on Postage Free Card

52 sportsTURF

WATERSCAPES BLEND AESTHETICOBSTACLES WITH WATER CONSERVATIONWaterscapes, designed to conserve

water and built to serve as water hazards-that's precisely what has been created bysome of America's top golf-coursedesigners. That is what golf coursearchitect Ted Robinson had in mind as heplanned the irrigation system for The IrvineCompany's new $10-million, championship-quality Tustin Ranch Golf Course in Tustin,CA.The 18-hole course's network of lakes,

cascading waterfalls and meanderingwaterscapes will not only serve as scenicand strategically placed water hazards, butwill also provide a functional irrigation sys-tem that will ultimately conserve millions ofgallons of water annually for OrangeCounty."The lakes scattered around the course

will provide golfers with handicapping yetbeautiful obstacles, while they serve thecommunity and the county by helping tosave precious water," said Robinson, whohas developed more than 120 coursesworldwide during the past 25 years."By using the lakes as reservoirs instead

of continually pumping water into the area,we can help conserve several thousand gal-lons of water every week," he observed.Robinson pointed out that using lakes as

water-saving elements at golf clubs, a tech-nique first developed in designing desertcourses, is becoming more common inwater-conscious areas of the country.Courses typically require a substantial

amount of water which can be wastedthrough improper intake levels, poordrainage, overflows and overwatering. Thesystem in the Tustin Ranch Golf Coursehelps eliminate water loss by hydraulicallymonitoring flows of reclaimed water whichis stored in lakes that are lined to preventseepage, he said."The system is extremely efficient,

because the only way water is lost isthrough evaporation," explained Robinson.When tully operational, the golf course

irrigation system will intake a continual flowof reclaimed water from two large reservoirsat the Michelson Reclamation Water Plantin Irvine. According to John Economides,senior engineer at the Irvine Water Districtwho helped plan the system, the water willbe pumped for nine hours each day. Duringthis period, as much as 1,000 gallons perminute will be piped into the lakes.Once in the lakes, water will be pumped

into the sprinkler system to irrigate grass,trees and natural foliage throughout thearea. Though this reclaimed water is puri-fied, regulations prevent it from being usedas drinking water, Economides said.During the 15 hours that the system is not

irrigating, water flows back into the lakes, aprocess which keeps debris such as dustand fallen leaves from stagnating in thewater.According to Economides, this refilling

process also helps relieve the strain on thewater company."The course's reservoirs help alleviate

some of our difficulties in serving the pub-lic during peak demand periods," saidEconomides. "Because the course has alarge water-storage capacity, we candecrease the strain on the community'swaterlines by redirecting the main flow tomeet needs in other parts of the local area:'To maintain the purity and luster of the

waterscapes, the course's intake systemincludes hydraulic jets that propel water upto the top of waterfalls, where it cascadesslowly down to the lakes and is then recy-cled back into the jets. This hydraulic sys-tem is also used within the lakes to forcemovement in the water and to provide anozonization treatment, a process that helpskeep the water clear and bacteria- andalgae-free.Although water conservation is of utmost

importance, the Tustin Ranch course'swater elements have also been developedto reflect the beauty and spirit of the localcommunity and to provide the ambience ofan upscale, top-quality golf course, accord-ing to Jim Colbert. He is head of Jim Col-bert Golf, Inc., Las Vegas, the companywhich is overseeing construction of thecourse and will manage it when completed."The challenge of the Tustin Ranch

project has been to blend a water-savingirrigation system with a well designed,attractive series of water hazards," said Col-bert, who has helped formulate severalProfessional Golf Association clubs alongwith providing commentary for ESPN's livegolf tournaments."What we've nearly finished creating is a

handsome, manicured lake and water-conservation system that imparts the feel-ing of a world-class golf course-one thatoffers area residents a quality club wherethey can enjoy their leisure time," Colbertsaid.Scheduled for completion in the summer

of 1989, the 160-acre course will include aclubhouse, driving range, putting green andother related facilities. The Tustin Ranchcourse is the first of several golf coursesplanned by the Irvine Company in newresidential communities in Laguna Canyon,Orange, and along the Irvine Coast inSouthern California.Tustin Ranch is a 1,740-acre community

along the eastern border of the city ofTustin. Planned for development over thenext nine years, it will ultimately include9,000 homes representing a balanced mixof hillside estates, single-family townhomes,condominiums and apartments.The community also includes more than

60 acres of neighborhood and communityparks, and 160 acres of commercial, officeand business centers including the recentlycompleted Tustin Market Place and theTustin Auto Center.

Page 3: IEEDlnG RATE: IT·' EffECT On DIIEA/E AnD WEED EnCROACHmEnTsturf.lib.msu.edu/page/1989feb51-60.pdf · 2009-06-04 · IEEDlnG RATE: IT·' EffECT On DIIEA/E AnD WEED EnCROACHmEnT By

PACIFIC SOD TOUGH!

Golf courses, sportsfields, and school-yards are child'splay when you'vemade the grade withthe pros.Durable, dense,resilient, PacificSod's sandy soilTifgreen and SantaAna are the choiceof most SouthernCalifornia golfcourses and athleticstadiums. They arealso a favorite ofparks, playgrounds,and active people!That's because thesefine textured hybridbermudas knowhow to play roughand keep on comingback.

So go ahead ...bring on yourgolfers, your altheticteams, your pets,your barbeques andyour heat wave. OurTifgreen and SantaAna are toughenough to take it.

Main Offices:Southern California305 W. Hueneme Rd., Camarillo, CA 93010 • (800) 762-3027

Northern California600 N. 2nd St., Suite 3, Patterson, CA 95363 • (800) 692·8690

Las Vegas, Nevada (702) 876-6252

"Pacific SodCircle 160 on Postage Free Card

Page 4: IEEDlnG RATE: IT·' EffECT On DIIEA/E AnD WEED EnCROACHmEnTsturf.lib.msu.edu/page/1989feb51-60.pdf · 2009-06-04 · IEEDlnG RATE: IT·' EffECT On DIIEA/E AnD WEED EnCROACHmEnT By

JACKIE ROBINSONSTADIUM UNDERGOESTURF RENOVATIONThe infield at Jackie Robinson Stadium

on the campus of UCLA in Los Angelesrecently underwent complete renovation.The project consisted of two major phases.First, the turf portions of the infield werestripped and regraded, and then theski n ned portion of the diamond wasreplaced and conditioned..'Ten days prior to the arrival of the Sports-fields, Inc., renovation crew the turf wassprayed with Roundup by UCLA Stadiumand Grounds Director Laura Adams. The

specialists in natural turf athletic field con-struction and renovation, who are based inBlue Island, IL, stripped the dead turf andremoved it from the site.The areas to be sodded were tilled and

soil was added as required. The groundwas fine graded and prepared for sodding.The crew installed 12,750 square feet of Tif-green (Pacific sod) Bermuda, which waswatered upon completion of the installation.

Due to the poor condition of the skinnedsurfaces of the infield, Adams requestedthat the upper four inches of the existinginfield mixture be removed and replaced.Approximately 175 cubic yards of DodgerBaseball M ixtu re was del ivered and

FAIRWAYCART PATHS

• An interlocking system of 1 squarefoot pavers which protects grass from.cart traffic.

• Balls bounce straight.

• Play is speeded up.

• Income is increased.

5" numbers imbedded in a 1 sq. ft. paverwhich lies level with the fairway. Useevery 10 yards for precise club selection.Legal under USGA Rule 24-2.

GOLF 2000 P AVERS9842 Hibert St. Suite 257

San Diego, CA 92131

1-800-824-9029 Tone 753Circle 167 on Postage Free Card

PARTAC®GOLF COURSE

TOP-DRESSING

VERTI·DRAIN® .

Works like apitcJJfork, ~ ~onlY better- ~ j

.x~ .'."~~ • ~/J-4~7' "#. • ;/k"

~ t's amazing how simple the principleis and how well It restores severelycompacted turf. Greens, fairways, sportsfields-anywhere you want to promotebetter root structure.

Our deep tine aerators godeeper than any others-lO",12" up to 16" deep. And our

patented process that shattersand lifts the turf like a pitch-

fork can't be duplicated.That's why world-wide

VERTI-DRAIN is therecognized leader. See

it for yourself.Call or write for our freeliterature, Videotapeor a demonstration

near you.

VERTI-DRAIN®415washington Avenue, Scranton, PA 18503

717·961·6120Circle 168 on Postage Free Card,

BOTHAVAILABLE IN

BULK OR BAGS

CAll TOll FREE:1-800-247-BEAM

IN N.J.201-637-4191PARTAC PEAT

CORPORATIONKELSEY PARK

GREAT MEADOWS,N.J.07838

N\~~MI!NA~I~I I., vAI1!IV//fllJIJ'kX//AMERICNS PREMIUM

TOP-DRESSINGHEAT TREATED

CONTROL THATCH,PROMOTE HEALTHY TURF

& SMOOTH PLAYING SURFACES

THE PROFESSIONAL'S CHOICE... SINCE 1922

BEAM CLAY IS THEBASEBALL MIXUSED BY

PROFESSIONAL TEAMS ACROSSTHE U.s.A. AND CANADA.

SPECIAL MIXES FOR PITCHER'SMOUNDS, HOMEPLATE AREAS

& WARNING TRACKS.

54 sportsTURF Circle 169 on Postage Free Card

graded. In addition, 14 tons of Turface wasincorporated into the Dodger mix, tilledonce again, fine graded, and rolled.The entire renovation took just six days to

complete and the field was expected to beready in less than two months. The cooper-ation between Sportsfields, Inc., and themaintenance staff at UCLA, includingAdams and her supervisor, Kyle Hackett,plus the baseball coach, Gary Adams,made the project a success.

PILOT FIELD RECEIVESDESIGN AWARDPilot Field, the new AAA baseball

stadium for the Buffalo Bisons, Buffalo, NY,has won the "Excellence in Design" awardpresented by the Kansas City chapter of theAmerican Institute of Architects (AlA).The ballpark, which is located adjacent to

a historical district of downtown Buffalo, wasdesigned by the HOK Sports FacilitiesGroup, Kansas City, MO.Joseph Spear, the principal designer of

the stadium, accepted the award while not-ing that the chief design challenge involvedraising community expectations and per-ceptions about what a baseball park couldbecome."It was necessary to allude to a period

when the national pastime was played inballparks, instead of circular concrete multi-purpose complexes," Spear said.Despite its capacity of 19,500 seats and

all the modern features and amenities, thebuilding is considerate of its neighbors andhas become a communal place for theentire community.Pilot Field was designed with expansion

capabilities to 40,000 to suit Major Leagueplay.

MORRIS NAMEDHEAD GROUNDSKEEPERGary Morris has been named head

groundskeeper of Joe Robbie Stadium andthe Miami Dolphins training camp in Miami,FL. by Glenn Mon, general manager of thestadium.Morris has had 15 years' experience in

turfgrass management. After completingthe turf management course at BrowardJunior College, he trained under Superin-tendent Larry Weber at Inverary CountryClub and the PGA National Golf Club, inPalm Beach, FL.He served as golf course superintendent

for four years at Emerald Hills Country Clubin south Florida, before leaving to helporganize the sports turf program for JoeRobbie Stadium and the Dolphins practice.fields at the training camp located at St.Thomas University.

Page 5: IEEDlnG RATE: IT·' EffECT On DIIEA/E AnD WEED EnCROACHmEnTsturf.lib.msu.edu/page/1989feb51-60.pdf · 2009-06-04 · IEEDlnG RATE: IT·' EffECT On DIIEA/E AnD WEED EnCROACHmEnT By

CHALKBOARD~

TIPS FROM THE PROSTHE BLACK LAYER: ONE SYMPTOM OF OXYGEN· DEPLETED SOIL

By Dr. Houston B. Couch

Tf we are going to deal effectively withthe black layer problem that is beingreported in various parts of the U.S.

and Canada, we should be devoting ourenergy toward research into the cause .anaerobiosis, or life in the absence of air .instead of one symptom, the black layer.Anaerobiosis is a dynamic series of

events which take place in an oxygen-depleted environment. When soil becomesanaerobic, there are significant changes inboth the form and the solubility of certainnutrient elements. While these nutrients arebeneficial in their standard form under nor-mal conditions, they can become toxicunder anaerobic conditions. In a reducedstate caused by lack of oxygen, these ele-ments may be taken up by the plant morerapidly than they can be metabolized,thereby becoming toxic.In addition, the root systems of plants do-

not function properly in anaerobic soils.Their ability to absorb water and nutrientsmay be reduced significantly.Furthermore, anaerobic micro-organisms

in the soil can produce metabolites that aretoxic to plants. These can cause either out-right death of the roots or an unthriftygrowth of the overall plant.While this problem is receiving more

attention than it did in times past, anaerobi-osis of bentgrass greens is not new. Forsome 30 years, I have observed bentgrassputting greens in this condition in variousstages of severity at a wide range of loca-tions in this country. During the past year, Ihave diagnosed cases of acute anaerobio-sis in plugs from putting greens with bothpredominantly sand and predominantly soilconstruction.Turf managers should understand that

sometimes a black layer accompaniesanaerobiosis and sometimes it doesn't. Thesame is true for a strong odor of hydrogensulfide or a high population of algae on thesurface of the green.The one thing all of these situations have

in common is an anaerobic conditioncaused by water filling all of the soil's porespaces. This water accumulation can bethe result of prolonged periods of rainfall, orimpaired infiltration brought on by eitherincorrect construction or an aerification pro-gram that included topdressing with animproper type of sand.Anaerobiosis can be accelerated by an

accumulation of algae on the surface of thegreen. Algae proliferate rapidly on greenswith a high sand content. This is probablydue to a number of facts.

Black layer profile in old green topdressed with sand.

First, algae grow better on wet, light,sandy soils. Microbial competition is not asgreat as that found in mixes where soil ispredominant. Irrigation practices on high-sand-content greens are often excessive.And finally, there is a wide "swing" in theavailability of various nutrient elements insand greens.Algae produce complex carbohydrates

(polysaccharides) that have the consistencyof gelatin. This material can move down-ward into the soil profile, plugging the poresand impeding the infiltration of water. Notonly do these polysaccharides contribute tothe development of an anaerobic conditionof the soil, but they also serve as a growthmedium for anaerobic microorganisms.Algae, then, can be an important factor inthe development of anaerobically induceddecline of turfgrass.An article in the June 1987 issue of Golf

Course Management theorized that sulfur isthe primary cause of anaerobiosis. Theauthors of these articles proposed that sul-fur, not excess water, initiates an anaerobicstate in the soil, and that sulfur (in the formof hydrogen sulfide) is the cause of plantdeath. Their premise centers primarilyaround the fact that sulfur does have thepotential for developing a blackened condi-tion in the soil. They were also able toproduce black layers with very high rates ofsulfur in their tests.Their hypothesis assumed that sulfur at

presently used rates will induce an anaero-bic condition in the soil and produce blacklayers, and that all conditions of anaerobi-

Black layer profile in new green with sandyroot zone mix.

osis in soils lead to the formation of blacklayers. None of these assumptions is cor-rect. In fact, the results of their tests showedthat sulfur applications within the normalrange do not produce black layers.The experimental design for this

research consisted of applying sulfur at twoseparate rates, one pound and five poundsper 1,000 square feet. None of theexperimental units treated with one poundof sulfur developed black layers, while 75percent of those treated with five poundsdid.Where sulfur and products containing

sulfur are concerned, there is no publishedscientific evidence that either elemental sul-fur or sulfur contained in currently used turffertilizers at recommended rates will cause

continued on page 56

February, 1989 55

Page 6: IEEDlnG RATE: IT·' EffECT On DIIEA/E AnD WEED EnCROACHmEnTsturf.lib.msu.edu/page/1989feb51-60.pdf · 2009-06-04 · IEEDlnG RATE: IT·' EffECT On DIIEA/E AnD WEED EnCROACHmEnT By

Black layer in sand bunker.

Chalkboardcontinued from page 55

or contribute to the development ofanaerobiosis. This means that sulfur at therates currently recommended will notinduce anaerobiosis ... and refraini ng from

using sulfur will not reduce anaerobiosis.The impact of anaerobiosis on plant

growth can be either chronic (of long dura-tion) or acute (sudden onset). It can exist insoil long before there is strong evidence ofaffected plant growth. It can exist without

producing black layers.Prevention of the problem is accom-

plished by close monitoring of the infiltra-tion rates of the greens. When the ratebegins to drop, even though it may notappear to be significant, direct measuresshould be taken to correct the matter.When it has been determined that

anaerobiosis has developed, steps shouldbe taken to increase the oxygen levels inthe root zone. This means following a water-ing program that allows the soil moisture tobe extracted well below field capacitybetween irrigations. It means aerification-including deep aerification if drainage bar-riers exist. It may also call for installing sup-plementary drainage for the greens.Another important aspect of preventing

anaerobiosis from developing to the acutestage is the control of surface algae. At thepresent time, the only pesticide that can beused on putting greens for algae control ismancozeb (Manzate, Fore, Tersan LSR).This material is effective in the control ofHelminthosporium-incited diseases, and isalso effective in reducing the impact ofPythium blight. Its inclusion in the sprayschedule can then serve more than onepurpose.

Editor's Note: Dr. Houston B. Couch isprofessor of plant pathology at Virginia Poly-technic Institute and State University inBlacksburg, VA.

Low cost, 3-phase irrigationwith single-phase power ...

PHASE CONVERTERSRonk Rotary or Static Phase a result of excellentConverters will convert engineering and designsingle-phase power to since 1950 ... givingoperate irrigation sys- "r-".!I.~~Ronk the com-tems on economical petitive edge inthree-phase. Ronk providing the veryoffers the latest "state- best converters.of-the-art" converters ...

Put a Ronk PowerConverter to workfor you and con-vert your irrigationsystem to moreprofitability.

Sendfor details on ourcomplete line.

Outside IL Ph. 1-800-221-RONK

ZN89~~202E. State St. • Nokomis, IL 62075 • Ph, 217/563-8333, Ext. 203

56 sporfsTURF Circle 171 on Postage Free Card

Uowtomakeyour career grow.Join PGMS.GROUNDSMANAGER:The Society treats your careerwith loving care with. the Annual Conference and Trade Show• the monthly newsletter. peer review to earn you the title ofCertified Grounds Manager • surveys on practices • $5.000.00accident and dismemberment insurance • awards for achieve-ment • workshops • discounts on rental cars and publications• Estimating guide. Management Guidelines. Forms and JobDescriptions. Join today. Yourcareer will take root andgrow.

Clip and mail to PROFESSIONAL GROUNDS MANAGEMENTSOCIETY. 12 Galloway Avenue. Suite IE, Cockeysville. MD21030 or phone (301) 667-1833

:TO: PROFESSIONALIGROUNDS MANAGEMENTI SOCIETY: ] 2 Galloway Aven ueSuite IE. Cockeysville, MD 21030

YESl I want to give my career a professional edge. Please send more in-formation on what PGMScan do for me.Name _

Company _

Street _

City &: State Zip _

Area Code and Telephone Number _~-----------------------------------~

Page 7: IEEDlnG RATE: IT·' EffECT On DIIEA/E AnD WEED EnCROACHmEnTsturf.lib.msu.edu/page/1989feb51-60.pdf · 2009-06-04 · IEEDlnG RATE: IT·' EffECT On DIIEA/E AnD WEED EnCROACHmEnT By

(9.l1I1JIRsr6.,2 Fits All Tractors

The Ultimate AeratorGreenCare has combined high-tech

engineering and simple design to produce thestrongest, most versatile and efficient aerator onthe market today. Vertical aeration combinedwith variable pattern, variable depth and a varietyof tine types and sizes provide today's TurfSpecialists with the tool they need to tailoraeration to their requirements.

Core Collection System• Simply attaches to rear of CoreMaster.• Auto-reset on next aeration pass.• Removes cores as you aerate and automat-ically dumps cores at the end of each run.

The Ultimate TopdresserGreenCare engineering leads the way in Turf

Equipment Innovation again:• All hydraulic drive.• Tubular steel and zinc annealed sheet metalconstruction.

• Roller drum eliminates conveyor belt problems.• Internal rotating baffle prevents "material surge"at the start of each run.

• Independent control of brush speed, drumrotation and gate opening provide precise rateof application.

• Flared top for easy filling with front-end loader.

• One man can do the work of four.• No other expensive machines or operators required.• On golf greens, play can continue during aeration.

C1~ LYJt:dJhj/ 7 ,'@ ~~:~:::~=WNLAN~HUNTIN:::~~~~H~~-::INTERNATIONAL

For more Information and your nearest distributor, contact the pros at GREENCARE. They'll be happy to share the news.

Circle 213 on Postage Free Card

Page 8: IEEDlnG RATE: IT·' EffECT On DIIEA/E AnD WEED EnCROACHmEnTsturf.lib.msu.edu/page/1989feb51-60.pdf · 2009-06-04 · IEEDlnG RATE: IT·' EffECT On DIIEA/E AnD WEED EnCROACHmEnT By

ROOKIES

DEEP-TINED AERATORS

The Model 105.145Verti-Drain deep-tinedaerator can alleviate the most difficult soil-compaction problems.The unit is powered by the PTa of a

category I or II tractor and is capable of aer-ating up to four acres a day. The aeratorcontinuously drives solid or hollow coringtines into the soil to depths ranging fromtwo to 16 inches.The rugged design permits the tines to

pivot back and forth, creating a lifting effect.This action combines penetration throughthe soil pan for vertical drainage with theshattering of the compacted layers forthorough aeration. The overall result is agreatly improved soil environment whichallows deeper, healthier root systems.The unit works well in all types of soils

and in a wide range of applications, includ-ing golf courses, parks and playgrounds,race tracks, tennis courts and athletic fields.VERTI·DRAIN USACircle 179 on Postage Free Card

SLOW-RELEASELIQUID FERTILIZERS

Four slow-release liquid fertilizers arenow available from Growth Products. Threeof the fertilizers are complete blends ofslow-release nitrogen, phosphorus, andpotassium in 26-0-0, 15-0-2, and 18-3-6 for-mulations. The-fourth solution, Micrel, con-tains EDTA micronutrients.58 sporfsTURF

".,.PRODUCT UPDATE

The fertilizers are packaged in 21f2-galloncontainers for convenient turf, tree andornamental application.GROWTH PRODUCTSCircle 175 on Postage Free Card

LOW-GROWTH TALLFESCUEA true dwarf, turf-type fescue, Shortstop,

has been developed by Dr. Jerry Pepin, abreeder for Pickseed West, Inc. The fescueexhibited a low- and slow-growth habit whentested at the company's research station.The low-growth rate, fine-leaf texture,

dark-green color, and its ability to producea dense, uniform turf in a variety of climaticand soil conditions make the fescue idealfor athletic fields, parks, golf course roughs,and low-maintenance areas.PICK SEED WEST, INC.Circle 176 on Postage Free Card

HOSE ADAPTER

The DRHA-1 DR Hose Adapter enablesRain Bird electric valve-in-head DR rotors tooperate as quick-coupling valves on the golfcourse. The adapter may be quicklyinstalled in the field by replacing the rotor'sinternal sprinkler assembly.This conversion is done in seconds by

using a convenient snap ring alreadypresent within the rotor. Once installed, theunit will accept a one-inch swivel hose ell fit-ting and in turn may be connected to a stan-dard hose.

The golf rotor can then be used to pro-vide spot watering, to mix chemicals, and towash down cart paths. It can also be usedto quickly flush out rotors without risk ofunwanted debris being washed back intothe rotor case or irrigation lines.The adapter is constructed of corrosion-

resistant plastic and works with any of theRain Bird DR golf rotors. It features a one-inch MPT outlet, which enables it to beused with swivel-hose ells and either 3/4- orone-inch hoses.RAIN BIRO SALES, INC.Circle 1n on Postage Free Card

HIGH-CAPACITY MOWER

Responding to the turf-maintenanceneeds of professional groundskeepers, TheToro Company has introduced a productive,maneuverable large-scale mower-theGroundsmaster 580-0 high-capacity turfmower.The unit's compact 80-hp turbo-diesel

engine provides power for cutting up to 14.5acres per hour while cutting a 16-foot-wideswath. However, its 76-inch wheelbaseallows for an 18-inch uncut circle withoutbraking.The outboard cutting units feature break-

away protection, so if the operator mis-judges distance and the unit strikes anobject, the wings will pivot away from it.In addition, the user can raise one or

both outboard cutting units inside the trac-tion unit width. This allows for trimmingbetween objects less that eight feet apart.The mower's rotating hinge lowers the

outboard cutting units behind the operator,providing a clear view to the side and rear.This simplifies transport because the cut-ting units' weight is rotated to the rear forbetter balance.Other important features include a tilt

steering wheel and column; three-wayadjustable seat; easily accessible controlsand cruise control.

THE TORO COMPANYCircle 178 on Postage Free Ca~d

Page 9: IEEDlnG RATE: IT·' EffECT On DIIEA/E AnD WEED EnCROACHmEnTsturf.lib.msu.edu/page/1989feb51-60.pdf · 2009-06-04 · IEEDlnG RATE: IT·' EffECT On DIIEA/E AnD WEED EnCROACHmEnT By

DITCHERSAWTHE WORLD'S MOST DEPENDABLE, VERSATILE

AND LIGHTWEIGHT PORTABLE TRENCHER

The Ditcher Saw's ingenious in-linedesign allows you to dig in those closequarters frequently encounteredaround shrubbery or close tobuildings. Plus, its two-wheel walk-behind design includes a special antikick-back stabilizer for operatorsafety. For added versatility, theDitcher can be detached and used byhand for trenching those extra-tightspots.

FEATURES:• The model A0300 digs a 2Y2" wide by22" deep trench at up to 20 feet perminute with minimum damage tolandscape.

• Rugged all-steel dolly quickly detachesto convert to hand operation.

• Powered by 3.5 cu in. Homelite engine.

• Case hardened teeth, spring loadedhead sprocket prevents chain lock-up.

Completely automatic centrifugalclutch.

• Depth selector maintains constantdepth.

• Easily loaded, transported andoperated by one person.

The Ditcher can also be used for transplanting or digging shrubs or small trees. Andbecause it leaves the soil compact on the roots for easy balling, the Ditcher will saveyou time and effort.

*Distributor and dealer inquiries welcome.

DITCHER SAW, INC., P.O. Box68, St. Mary's, WV 26170-0068 • (304) 684-3800Circle 159 on Postage Free Card

Page 10: IEEDlnG RATE: IT·' EffECT On DIIEA/E AnD WEED EnCROACHmEnTsturf.lib.msu.edu/page/1989feb51-60.pdf · 2009-06-04 · IEEDlnG RATE: IT·' EffECT On DIIEA/E AnD WEED EnCROACHmEnT By

LET PLASTRO MAKEA STAKE IN YOURFUTUREWITN

• Can be used in an inverted position while a tree is youngthen repositioned upright as the tree matures.

• Hammer top eases Installation.• Accommodates most standard tube sizes.• AVAILABLE IN ORANGE OR BLACK.• Durable constructIon.• priced competitively.• Available as complete unit with your choiceRay..Jets or Mlni..sprinl<lerr~

TORNADOMini-Sprinklers• larger water passagesprevent blockage--even with low flow rates.

• Anti-insect device covers and protectsnozzle.

• Available In standard flow ratlS.

TORNADORay-Jet Sprayer• significantly larger water passages. NOmoving parts.

• Available in 360-, 300- and 180-degreespray patterns.

• Available in standard flow rates.-.Critical water passagesTORNADO vs. Conventional Spray Head

Flow-rate TORNADO Nozzle diameter Increase Ingph passage conventional net passage areadiameter spray head

11 0.050" 0.035" 165%

self-cleaning operation -- special vortex rnecharilsm withlarge passage design enables steady flow.The most even distribution of water available.

r;::::;I ~Iastro-c.I irrigation inc.

Circle 207 on Postage Free Card

CONTACTYOURLOCALDEALEROR: 260LinkRoad suite C,Suisun,CA94585. Tel:U.S.1-800-PLASTRO707-864-5490