A Breakthrough in Organic Turfgrass ManagementDR. WILLIAM A. TORELLO, DR. HAIM B. GUNNER AND DR. MING J. COLER, ECOORGANICS, INC.

IntegratedPest Management (IPM)programs have been developed foralmost all agricultural and ornamen-

tal crop production systems over the pasttwo decades but only recently have IPMand organic management systems beenconsidered a truly primary approach inprofessional turfgrass management. Thereasons for the dramatic increase in or-ganic approaches are centred upon publicconcern for the environment which hasresulted in legislation at both the stateand federal level in reducing or elimi-nating pesticide and synthetic fertilizerusage.

Although the industry has been 'pushed'into using IPM and organic approaches, amultitude of research reports as well ason-site experiences have shown thatswitching partially or even wholly to or-ganic management techniques has resultedin renewed and greatly increased turfgrassperformance while reducing or eliminat-ing pesticide and synthetic fertilizer us-age.

One of the more significant problemsassociated with organic turfgrass manage-ment programs, particularly in the golfcourse and sports turf industry, has beenthe inability to develop and maintain thehigh levels of overall turf quality and ag-gressiveness (recuperative potential) withnatural organic fertilizers that are nowexpected.

Natural organic fertilizers are inher-ently low in available nitrogen levels rang-ing, for the most part, between 2 and 8%with only blood meal and bat guano ap-proaching the 10-12% levels. These rela-tively low nitrogen levels (compared tosynthetic sources) make it necessary toapply inordinately high amounts of mate-rial to achieve the desired seasonal effectssince all natural organics depend upon soilmicrobial activity for nitrogen/mineralrelease.

As such, when soil temperatures arelow as in the spring and fall, release ratesare limited at a time when cool-seasonturfgrasses are at their peak of perform-

6 • DECEMBER 200 1

ance and need higher levels of nitrogen inthe development of root zones and lateralstems. This is particularly the case whenusing materials lower than 6% N having acomparatively high CIN (CarbonlNitro-gen) ratio which would result in evenslower mineral release.

To overcome this problem, the indus-try has developed 'organically based' fer-tilizers that have increasing levels ofinorganic nitrogen added to meet the highN demands. These 'bridged' products havebeen successful but cannot be considered100% natural organic and can result inincreased nitrogen loss through surfacerunoff and leaching to ground waters, de-pending on how high the percentage ofinorganic N. Inorganically 'amended'materials also do not have the same abil-ity to stimulate increases in soil microbialactivities and populations so necessary fora healthy soil under reduced or limitedpesticide programs.

It has been well documented over theyears that increased soil microbialpopulations and activities compete withand suppress the populations and activi-ties of soil-borne plant pathogens result-ing in significantly less disease occurrenceand subsequent damage (references 1,2).Aside from temperature and adequatewater levels, the amount and types of or-ganic matter and fertilizers will have anextremely profound effect upon nutrientavailability as well as disease suppression.Some types of organic amendments, par-ticularly those with comparatively low C/N ratios, have been known to greatly sup-press levels of disease incidence (3, 4).

The literature published regarding the

effects and potential use of organic ferti-lizers and amendments on professionalturf, particularly in the last 10 years, isvoluminous but can be summarized asfollows:

Disadvantages1. Nitrogen levels too low to maintain

higher performance turf requiring amore rapid response.

2. Very high levels of material need to beapplied to achieve desired results.

3. Almost all materials are applied in apelletized, solid application which caneasily be picked up during mowing andtake considerable time to breakdownand release mineral nutrients.

4. Materials having high CIN ratios haveextremely long residual times and may'bind' available nitrogen.

5. Seasonal effectiveness: organic fertiliz-ers depend upon microbial activities formineral release and, as such, on irri-gated systems, are much more effec-tive during the warm summer monthsand not adequate during the highgrowth fall and spring seasons.

6. Bulky to store and transport due to com-paratively low nitrogen analysis.

7. May have a naturally foul smell.8. Usually much more expensive com-

pared to inorganics and urea.

Advantages1. Environmentally friendly: little or no

nitrate leaching or runoff into groundor surface waters.

2. Increased soil microbial populationsand activities.

3. Decreased disease incidence due to en-hanced competitiveness by increasedsoil microbial populations.

4. Decreased thatch accumulation due toincreased soil microbial populations.

5. Increased nutrient availability due toenhanced decomposition by soil micro-bial populations.

6. Increased soil water holding capacity.7. Little to no salt index making high tem-

perature applications safe.

In view of the previously listed disad-vantages, the most desirable natural or-ganic fertilizer would have the followingproperties:A. The highest level of nitrogen available,

preferably over 12% N.B. The lowest C'N ratio possible, prefer-

ably under 20 for more rapid microbialbreakdown and nitrogen availability,particularly during the spring and fallmonths.

C. Easy application, preferably a liquidsoluble/flowable spray application toavoid particle pickup during mowingand to enhance response time.

D. High microbial populations and activi-ties after application.

Until recently, the only way to approachthe properties listed above was to blendan amended 'organically based' materialwhich would have a base level of naturalorganic component mixed with a high Nanalysis inorganic or urea fertilizer. Un-

fortunately, although these materials meetplant nitrogen demands, they fall shortwith regard to increasing soil microbialactivities/populations and decreasing dis-ease incidence and are not in compliancewith 'natural organic' standards. Theseinorganic/organic blends also have muchmore potential for eventual nitrogenmovement to ground and surface waters.The only 100% natural organic that comesclose to the above properties is blood mealwhich has up to 12% nitrogen and can besuspended in water for spray applicationsbut, unfortunately, blood meal is ex-tremely expensive to produce eliminatingany feasible commercial use. Only onerecently developed material (spring, 2001)called BioSOF Plus meets all the criteriaoutlined above. This material has the high-est level of natural organic nitrogen to datein the industry at 14.0% which is plantderived from a complex series of extrac-tions from soybeans. The material is com-posed of approximately 20% free amino

acids and 70% short chain proteins andpeptides which makes the material ex-tremely dispersible in water and, as such,very flowable allowing for liquid sprayapplications or additions to fertigationsystems. BioSOF Plus has almost unlim-ited storage capacity and transport is ac-ceptable due to the solid, powdered natureof the material and high nitrogen content.The protein content of BioSOF Plus is inexcess of 90% which gives it the extremelylow C/N ratio of 2.2 making it a powerfulsoil microbial biostimulant. In view ofthese characteristics, BioSOF Plus repre-sents a significant breakthrough in the or-ganic management of professional turf.

Objectives and MethodsThe objectives of this report are to com-

pare BioSOF Plus with a standard andcomparable inorganic source having ap-proximately the same analysis andmilorganite, a popular composted sludgeused extensively in the turf industry. Data

Contour Mowing Flexibility.FIVE INDIVIDUAL FLOATING MOWER DECKS.Produces a superior cut while conforming to undulations, bumps

and hollows. Ideal for any grounds maintenance applicationdemanding superlative results.

Tn-Deck Rotaryinishing Mowers.

QUALITY PLUS!Progressive Mowers: Designed with quality andvalue to exceed all requirements for any finishmowing application.

LlTLRFCARE200 Pony Drive, Newmarket, ON L3Y 7B6Tel: 905-836-0988 • Fax: 905-836-6442Visit us online at www.turfcare.ca.

Contact your Turf Care salesrepresentative for more details.

SPORTS TURF MANAGER • 7

were taken on overall turf quality everytwo weeks from experimental field plotsof 'Providence' and 'PennCross' creepingbentgrass throughout the growing seasonof 2000. Microbial activity and popula-tion analysis for these materials was ob-tained by sampling of the soil profile 3, 7and 10 days after each application of allmaterials followed immediately by astandard plate count method of quantify-ing soil microorganisms. Rates of appli-cation were 0.1, 0.2 and 0.31b N/I000 sq.ft. applied monthly on native soil sites and0.3 lb N/lOOO sq. ft. weekly on standardUSGA sand greens and modified USGAsand greens mixed with 30% native soil.

ResultsTurfgrass quality ratings between

BioSOF Plus and inorganic treatmentswere surprisingly similar for all three soiltypes tested. Application rates between 0.1and 0.3 lbs N/I000/month on native soilresulted in virtually no significant differ-ences between BioSOF Plus and the inor-ganic treatments over the course of thegrowing season. A weekly application rateofO.31bs N/lOOOsq. ft. on both the USGAsand green profile and the modified sandprofile again indicate that there are noobservable differences in turfgrass qual-ity between BioSOF Plus and inorganictreatments.

Microbial population counts for allthree soil profiles showed dramatic differ-ences between BioSOF Plus, inorganicand milorganite within three days aftereach application. Applications of BioSOFPlus to the USGA pure sand profile re-sulted in explosive growth of microbialpopulations compared to the inorganic andmilorganite treatments. BioSOF Plus ap-plications for the modified sand and na-tive soil profiles were similar yielding upto 600% more microbial activity com-pared to the other treatments within 72hours.

ConclusionsTurf Quality Ratings

Turf quality ratings for all soil typesshowed no differences between BioSOFPlus and inorganic treatments indicating,for the first time, that a 100% natural or-ganic material can perform equally as well

as an inorganic during a 'spoon feeding'program, particularly to USGA sandgreens. The low CIN ratio of BioS OF Plus(2.2) and the fact that the material is com-posed of highly degraded short chain pro-tein/peptides and amino acids results inintensive soil microbial activity leading toan extremely rapid mineralization proc-ess and nitrogen availability levels ap-proaching that of immediately availableinorganic applications.

Soil Microbial ActivityApplications of BioSOF Plus result in

extremely rapid and large increases inexisting soil microbial populations com-pared to milorganite and inorganic nitro-gen treatments. This rapid response isagain due to the low CIN ratio of the ma-terial as well as the fact that the BioSOFPlus was applied as a flowable liquid spray(flowable powder) which would carry thematerial into the soil more effectively aswell as have a much larger surface areafor microbial activity.

The results obtained during the 2000growing season clearly indicate BioSOFPlus to be equally as effective as inorganicapplications with regard to overall turfquality but much more effective in stimu-lating existing soil microbial populations,even on a 100% sand profile, comparedto inorganic and milorganite treatments.Although turf response was similar to in-organic treatments, there was no observ-able 'flush' of growth with BioSOF Plusapplications and there is literally nochance of foliar burn due to the organicnature of the product. It can reasonablybe concluded that soil borne disease ac-tivity would be much less on BioSOF Plustreated turf compared to inorganic or evenmilorganite treated turf due to the explo-sive increases in soil microbialpopulations.

The most important conclusion is thefact that BioSOF Plus meets all the crite-ria listed above as the 'most desirable'organic fertilizer source having the high-est level of organic N in the industry at14.0%, flow able characteristics of thematerial allowing for more effective liq-uid applications from spray tanks orfertigation systems, an extremely low C/N ratio with rapid and significant stimu-

lating effects on soil microbialpopulations. The physical characteristicsof BioSOF Plus as well as plant and soilresponses clearly make this material abreakthrough in organic management ofturf as well as other agricultural sys-tems .•

Literature Cited1) Boland, GJ. and Kuykendall, L.D.

1998. Plant-microbe interactions andbiological control. Marcel Dekker, N.Y.

2) Deacon, J.W. 1991. Significance ofecology in the development ofbiocontrol agents against soil-borneplant pathogens. Biocontrol Scienceand Technology 1:5-20.

3) Nelson, E.B. 1997. Biological controlof turfgrass diseases. Golf CourseManagement 65(7):60-69.

4) Nelson, E.B. and Craft, C.M. 2000.Microbial strategies for the biologicalcontrol of turfgrass diseases. In: lM.Clark and M.P. Kenna, (eds) Fate andManagement of Turfgrass Chemicals.American Chem. Soc., Washington, D.C. ACS Symposium Series 743:342-352.

Dr. William A. Torello is Associate Professorof Plant and Soil Sciences at the Universityof Massachusetts as well as Executive VicePresident for EcoOrganics, Inc.

Dr. Haim B. Gunner is an Emeritus Profes-sor of Environmental Microbiology at the Uni-versity of Massachusetts as well as Presidentand CEO of EcoOrganics, Inc.

Dr. Ming Coler is an Environmental Micro-biologist with extensive research experiencein soil and aquatic ecosystems. Dr. Coler isCFO and Co-Director of Research forEcoOrganics, Inc.

Editor's Note: Dr. Brian Hall will be address-ing the topic of Organic Amendments, followedby a Panel Discussion on Organics at theupcoming Ontario Turfgrass Symposium.January 22-24, 2002.

Publication of this article does not imply theendorsement of BioSOF Plus by the SportsTurf Association. Availability in Canada willdepend on the supplier obtaining registrationof the product under the Fertilizer Act.

SPORTS TURF MANAGER • 9