could a residential wood ash recycling …...as wood ash can be used as a restorative additive to...

COULD A RESIDENTIAL WOOD ASH RECYCLING PROGRAMME HELP SOLVE THE CALCIUM DECLINE PROBLEM: INSIGHTS FROM A MUSKOKA WOOD BURNER’S QUESTIONNAIRE

Shakira Azan, PhD

ii

We gratefully acknowledge the financial support for this research provided by

Copyright © 2017 Friends of the Muskoka Watershed

This work is licensed under the Creative Commons Attribution-ShareAlike 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by-sa/4.0/ or send a letter to Creative Commons, PO Box 1866, Mountain View, CA 94042, USA.

Report # 2017-10-HATSEO-1

Please direct all questions and comments to: friends@fotmw.org

i

ACKNOWLEDGEMENTS

Wethankthe53Muskokaresidentswhocompletedthequestionnaireontheirwoodash

generation and use, Joel Yan for pointing us to the biennial survey on primary heating

systems in Canadian households conducted by Statistics Canada, and Norman Yan for

commentsondraftsofthisreport.

ii

TABLEOFCONTENTS

ACKNOWLEDGEMENTS...........................................................................................................................................................i

TABLEOFCONTENTS..............................................................................................................................................................ii

LISTOFFIGURES......................................................................................................................................................................iii

LISTOFAPPENDICES..............................................................................................................................................................iii

1.0 INTRODUCTION...........................................................................................................................................................1

2.0 SURVEYRATIONALE.................................................................................................................................................2

3.0 METHODOLOGY...........................................................................................................................................................3

4.0 FINDINGSOFTHEWOODASHSURVEY............................................................................................................3

4.1 Woodasaheatingsource....................................................................................................................................3

4.2 Mainsourceofwood..............................................................................................................................................3

4.3 Partsoftreeusedtoproducewoodash..........................................................................................................4

4.4 Treespeciesusedtoproducewoodash..........................................................................................................5

4.5 Currentusesofwoodash.....................................................................................................................................6

4.6 Seasonalashproduction.......................................................................................................................................7

4.7 Participationinresidentialwoodashprogramme....................................................................................7

4.8 Bucketsofashproducedduringheatingseason.........................................................................................9

4.9 Numberoffacecordsburntduringheatingseason...................................................................................9

5.0 GAPSANDRECOMMENDATIONS.....................................................................................................................11

6.0 ISTHEREENOUGHWOODASHTOHELPSOLVETHECADECLINEPROBLEM?.........................11

7.0 REFERENCES.............................................................................................................................................................15

APPENDIX..................................................................................................................................................................................17

iii

LISTOFFIGURES

Figure1:Piechartshowingpercentageofwoodorwoodfueltypesusedbyrespondents.....................4

Figure2:Piechartshowingpercentageofmainpartsoftreesusedbyrespondentsinwoodash

production....................................................................................................................................................................................5

Figure3:Piechartshowingpercentageoftreespeciesusedbyrespondentsinwoodashproduction

............................................................................................................................................................................................................6

Figure4:Piechartshowingpercentageuseofwoodashproducedbyrespondents..................................7

Figure5:Piechartshowingwillingnessofrespondentstoparticipateinaresidentialwoodash

recyclingprogramme...............................................................................................................................................................8

Figure6:Piechartshowinghowmanybucketsofashareproducedbyrespondentsduringthe

heatingseason..........................................................................................................................................................................10

Figure7:Piechartshowingthedistributionoftheamountofwood(infacecords)burntperyear10

LISTOFAPPENDICES

Appendix1:SurveyofwoodashusersinMuskoka................................................................................................18

1

1.0 INTRODUCTION

Overthepastseveraldecades,calcium(Ca)concentrationshavebeendeclininginMuskoka

lakes and forests. In 2014,TheMuskokaWatershed Council’s Report Cardhighlighted Ca

declineasanewenvironmentalstressoraffectinglakehealthinthearea.Thedamagecaused

bydecliningCaconcentrationisallaroundus.Inforests,lossofCahasresultedinslowed

growth,seedproduction,seedlingregenerationanddiebackofsugarmaplethatcanimpact

maplesyrupproduction.Inlakes,crayfishthathavehighCa-demandsaredisappearing.Last,

in offshore waters, a jelly-clad water flea, Holopedium, is replacing its more Ca-rich

competitors,andcreatingthepotentialtoclogwaterfiltersforresidentsdrawingtheirwater

fromlakes.

One possible solution to combatting Ca decline is active local engagement, ifMuskokans

become“gardenersoftheforest”.Asgardeners,wecanusewoodash-theresidueremaining

afterthecombustionofwood–toreturnCatoforestsoilswhereitoriginated.Woodash

containsmanyelements–bothmajorandminor–thatarerequiredfortreegrowth(e.g.,

calcium,potassium,nitrogen,phosphorus).Oftheelementspresent,Caisthemostabundant

withcalciumcompoundsformingbetween15%1and50%2oftotalashweight,followedby

potassium(K),magnesium(Mg),aluminium(Al),iron(Fe)andphosphorus(P).3Duetoits

highCacontent–mainlyascalciumcarbonate(CaCO3)-woodashisrelativelyalkalineand

canbeusedasagardenfertilizer.Inaddition,woodashcanbeusedforpestcontrol,tomake

soap, tomelt iceandsnow,absorbodours, removeoil stainsondrivewayorgarage,and

polishsilver.

2

Theuseofwoodashasaforestorsoilamendmentisnotunusual.Innorth-eastUnitedStates

ofAmerica,80%ofwoodashproducedisusedinlandapplication1.InEurope(e.g.,Sweden,

Finland,andUnitedKingdom),woodashisoftenaddedtoforestsoilstoenhancebiomass

production. In Canada,wood ash ismainly used for liming and/or fertilizing in Alberta,

British Columbia, NewBrunswick, Nova Scotia, andQuebec. In Ontario,wood ash is not

regularlyusedasasoilamendmentonagriculturalorforestsoils,andtherearecurrentlyno

guidelinesforsuchuses.4

2.0 SURVEYRATIONALE

Aswoodash canbeusedas a restorativeadditive to gardenand forest soils, andas ash

recycling programmes have worked in other countries (e.g., Sweden and Finland), the

FriendsoftheMuskokaWatershed(FMW)decidedtogainanunderstandingofwoodash

productionanduseintheMuskoka.Ourprimaryobjectivesweretodetermine:1)themain

sourcesofwoodusedduringtheheatingseason;2)ifandhowMuskokanswerewillingto

participateinaresidentialwoodashrecyclingprogramme;and3)howmanybucketsofash

areproducedduringtheheatingseason.Thissurveyfallsundertheumbrellaofthe“Hauling

Ash to Solve Ecological Osteoporosis” or “HATSEO” project that is funded by anOntario

TrilliumFoundationSeedGrantandaimstoturnawasteproduct–woodash–intoauseful

fertilizerthatcombatsCadecline.

3

3.0 METHODOLOGY

TheSurveyofWoodAshUsersinMuskokawaspreparedanddistributedtoFMWmembers

andpostedontheFMWwebsite1onMarch7,2017.Electroniccopiesofthesurveywerealso

senttoLakeofBaysAssociation,KawagamaLakeCottagersAssociation,andthelocalbranch

oftheOntarioMapleSyrupAssociation(SweetwaterMapleSyrupSuppliesandSugarbush).

The survey was also promoted via individual Twitter and/or Facebook pages, and

distributionlists.AcopyofthequestionnaireisattachedasAppendix1.

4.0 FINDINGSOFTHEWOODASHSURVEY

4.1 Woodasaheatingsource

Intotal,53completedquestionnaireswerereceivedandallrespondentsusedwoodorwood

productsasaheatingsource.Therewasnoindicationthatresidentsusedthewoodforother

purposessuchasmaplesyrupproduction,bonfires,eliminationofgardenoryardwaste,or

woodfiredcooking.

4.2 Mainsourceofwood

ThemainsourceofwoodashproducedinMuskokawasfromhardwood,whichwasusedby

57%oftherespondents.Twenty-sixpercentoftherespondentsused ‘mixed’wood, i.e.,a

mixture of hardwood tree pieces purchased froma supplier. Softwood andwoodpellets

werenotaswidelyusedashardwoodtreespecies,andaccountedfor14%and3%ofthe

respondents,respectively(Figure1).Biocharwasnotusedbyanyoftherespondents.

1http://friendsofthemuskokawatershed.org/hatseo-survey/

4

Figure1:Piechartshowingpercentageofwoodorwoodfueltypesusedbyrespondents

4.3 Partsoftreeusedtoproducewoodash

Themajorityoftherespondentsusedthestemortrunkoftreesasaheatingsource(44%).

Otherrespondentsusedthebark(30%)orbranches(26%)(Figure2).Treerootsorfoliage

werenotusedbyanyoftherespondentstoproducewoodash.

26%

57%

14% 3%

Mixed

Hardwood

Softwood

Woodpellet

5

Figure2:Piechartshowingpercentageofmainpartsoftreesusedbyrespondentsinwoodash

production

4.4 Treespeciesusedtoproducewoodash

Manytreespecieswereusedasfuel,andthustoproduceashinMuskoka.Themajorityof

therespondentsusedthehardwoodtreespeciesmaple(29%)toproducewoodash.Other

hardwoodspeciesusedwerebeech(19%),oak(17%),birch(14%),ash(4%),andcherry

(2%). Aspen, basswood, elm, moose-maple, and poplar, each accounted for 1% of the

responses(Figure3).

Softwood treespecieswerealsoused toproducewoodash,but in smalleramounts.The

softwoodspecieshemlockandpine,bothaccountedfor2%oftherespondents.Spruce,cedar

andbalsamwerealsoused,buteachaccountedfor1%oftheresponses.Fourpercentofthe

respondentshadnoknowledgeofthetreespeciestheyused(Figure3).

30%

26%

44% Bark

Branch

Stem/Trunk

6

Figure3:Piechartshowingpercentageoftreespeciesusedbyrespondentsinwoodashproduction

4.5 Currentusesofwoodash

ThemajorityofwoodashproducedinMuskokaisusedasfertilizeringardens(39%)(Figure

4).Otherprimaryuses includedcompost(24%),andmelting iceandsnowondriveways

(19%).Fewrespondentsusedwoodashintheirhomes(3%)(e.g.,cleaningglassonthewood

stove) and for pest control (3%). In contrast, some respondents did not use wood ash

produced,butdisposedof it in themunicipal landfill (4%),or ina forestedareaon their

property(6%)(Figure4).

19%

29%

17%

14%

4%

2% 2%

2% 1%

1% 1% 1% 1% 1% 1% 1% 4%

Beech

Maple

Oak

Birch

Ash

Cherry

Hemlock

Pine

Elm

Poplar

Cedar

Aspen

Spruce

7

Figure4:Piechartshowingpercentageuseofwoodashproducedbyrespondents

4.6 Seasonalashproduction

Ofthe53respondentsthatsubmittedacompletedquestionnaire,35(66%)usedwoodasa

heating source only in thewinter. The remaining 18 respondents usedwood during the

winterinconjunctionwithfallandspring(50%),fall,springandsummer(44%)orfallalone

(6%).

4.7 Participationinresidentialwoodashprogramme

Ofthe53respondentsthatsubmittedacompletedquestionnaire,only3personswerenot

interested in participating in a wood ash recycling programme. Most of the willing

participantspreferredtotransporttheirwoodashtothemunicipal landfill(29%)ortoa

centralizedlocationclosertohome(23%)(Figure5).Eighteenpercentoftherespondents

24%

39%

19%

3%

3% 4%

6% 2%

Compost

Fertilizer

Driveway

Pest

Inthehome

Disposal- landfill

Disposal- woods

Other

8

werewillingtoseparatewoodashfromorganicwasteforcurbsidepickup.However,this

activity is likelynot feasibleas theDistrictofMuskokaMunicipalityhas indicated that it

wouldbeanexpensiveundertaking.

Muskokanswere alsowilling to participate in the distribution ofwood ash to the forest

(15%),tohelppromoteandparticipateinan“ashdrive”gearedtowardscollectingwoodash

inandaroundMuskoka(8%),ortoserveonawoodashrecyclingprogramme’sadvisory

committee(4%).Threepercentoftherespondentspreferredtocontinuedisposingofwood

ashinaforestedareaontheirownproperties(Figure5).

Figure5:Piechartshowingwillingnessofrespondentstoparticipateinaresidentialwoodash

recyclingprogramme

29%

23% 18%

15%

8% 4% 3%

Landfill

Closetohome

Curb

Ashdistributn

Ashdrive

Advisory

Other

9

4.8 Bucketsofashproducedduringheatingseason

Duringtheheatingseason,30%oftherespondentsproducedeithermorethan20buckets

ofwoodashor5to10buckets,whereas28%producedeither10to20buckets(Figure6).

Incontrast,fewrespondentsproducedsmallernumbersofbucketsofash.Forexample,3to

5buckets(10%)and1to2buckets(2%)(Figure6).

IfweassumethataMuskokanusesanashbucketthathasavolumeof17.7L(3.9gal)5,the

mostcommonsize,thenthe53respondentswouldproduceabout12151L(~3210gal)of

woodash.Giventhatthedensityofwoodflyashis548kgpercubicmetre6,thenthese53

Muskokanswould produce, on average, 125.6 kg ofwood ash per individual during the

heatingseason.

4.9 Numberoffacecordsburntduringheatingseason

Theamountofwood(infacecords)burntduringtheheatingseasonvaries.Themajorityof

therespondentsburntmorethan5facecords(38%)duringtheheatingseason(Figure7).

Otherrespondentsburntbetween1and2facecords(22%),2to3facecords(16%),4to5

facecords(12%)or3to4facecords(10%)(Figure7).Fewrespondentsburntlessthan1

facecord(2%).

Overall,the53respondentsburnt176.5facecordsduringtheheatingseason.Asafacecord

is1/4afullcord(weighsapproximately2tons)7,thenonaverage,about1500kgofwoodis

burntperindividualduringtheheatingseason.

10

Figure6:Piechartshowinghowmanybucketsofashareproducedbyrespondentsduringthe

heatingseason

Figure7:Piechartshowingthedistributionoftheamountofwood(infacecords)burntperyear

2% 10%

30%

28%

30%

1to2

3to5

5to10

10to20

>20

2%

22%

16%

10% 12%

38% 0to1

1to2

2to3

3to4

4to5

>5

11

5.0 GAPSANDRECOMMENDATIONS

ThepurposeoftheSurveyofWoodAshUserswastogatherinformationonwooduseand

wood ash production inMuskoka. The surveywas distributed tomembers of the FMW,

cottageassociations,andmaplesyrupproducerswhowerethoughttousewoodasaheating

source.WithinMuskoka,thereare60,599permanentand85,163seasonalresidents8.If3%

ofthepopulationheatswithwood9,thenthenumberofsurveyresponsesreceived(<1%of

the number that heatwithwood)may not be a representative sample. A larger sample

shouldbesought,asitislikelymoreinformationwillbeneededtodeterminethefeasibility

ofestablishingaresidentialwoodashrecyclingprogrammeinMuskokathathasthepurpose

ofhelpingtosolvetheenvironmentalCadeclineproblem.Inaddition,moreinformationon

woodashproductionwouldassist indetermining if enoughwoodashcouldbecollected

fromresidencesand/orcommercialbusinessesfordistributiontothenorth-easternportion

ofthe2EBWatershed,i.e.,theHollowRiverQuaternaryWatershed,where>50%ofthelakes

haveCalevelsbelow1.5mgCa/L,alevelatwhichCa-richbiotasufferpopulationdamage.

6.0 ISTHEREENOUGHWOODASHTOHELPSOLVETHECADECLINEPROBLEM?

Scenario1

Thereare60,599permanentresidentsinMuskoka,ofwhich3%heatwood.Assumingour

surveyprovidedaccurateestimates,themajorityofMuskokansthatheatwithwoodproduce

about20bucketsofashperheatingseason,whichequatestoapproximately36,359buckets

ofwoodashinthewatershed.Assuminganashpailholds17.7L,permanentresidentswould

12

generateabout643,561L(644m3)ofwoodash.Asthedensityofwoodashaveragesabout

548kgper cubicmetre6 (it varieswithwood species), approximately352,672kg (~353

tonnes)ofashwouldbeproduced.Asoursurveyindicated2/3oftherespondentswouldbe

willingtotransportwoodashtothedumporlandfill,oranearbytransferstation,theycould

provideabout235,000kg(235tonnes)ofashperyeartoawoodashrecyclingprogram.

ThisamountofashwouldbeenoughtotreattheCadeclineprobleminroughly58hectares

ofMuskokaforestatanapplicationrateof4tonnesperhectareperyear.Storageofthismuch

woodashforannualdistributionrequiresa500m3building,andthesearereadilyavailable

forsaltstorage.

Scenario2

Thereareanestimated145,762residents(permanentandseasonalcombined)inMuskoka,

especiallyduringthesummer.If3%heatwithwoodandgenerate20bucketsofash,87,457

bucketsofwoodashwouldbeproduced.A17.7Lpailwouldgenerateabout1,547,992L

(~1548m3)ofash.If2/3oftheresidentsarewillingtotransportwoodashtothelandfill,

thenFMWwouldhave~566,000kg(566tonnes)ofashavailableperyear.Withthisamount

ofash,approximately140hectaresofMuskokaforestcouldbetreatedatanapplicationrate

of4tonnesperhectareperyear.

Conclusion

Witheitherscenario,theamountofwoodashgeneratedfortheapplicationof1tonneper

hectare,iscertainlyadequateforalargescalepilotprojectorfeasibilitystudyonwoodash

13

collectionandapplication;however,notenoughtosolvetheproblemacrossMuskoka,given

thewidespreadnatureofCadecline.

TosolvetheCaproblem,i.e.,eliminateCalimitationoftreegrowth,andprovideexcessCa

that couldenter lakewaters, aminimumofabout4000kg (4 tonnes)perhectareofash

wouldlikelyneedtobeapplied(CarolynReid,TrentUniversity,pers.comm.).TheHollow

RiverWatershedisapproximately40,000hectares.If53residentsproduceabout12,151L

ofashthatwouldweighroughly6659kg(~7tonnes),thenFMWwouldrequirewoodash

fromabout41,000peopletotreattheentirewatershed.Therearecertainlyenoughpeople

intheprovincethatheatwithwoodtoprovidethismuchash,butnotinMuskokaalone.

Asof2016,Ontario’spopulationwas13.9M.Ofthese,1%usewoodorwoodpelletsastheir

primaryheatingsystem.Assumingeachofthesepersonsgenerate20bucketsofash,then

about2.8Mbucketsofashwouldbeproduced.Assuming17.7Lpails,Ontariowoodburners

wouldgenerateabout49.5ML(~50,000m3)ofash.Assuming2/3ofresidentsinOntario

arewillingtotransportwoodashtothelandfill,thenFMWwouldhave~18.1Mkg(about

18000tonnes)ofashavailableperyear.Therefore,FMWcouldtreatapproximately4,500

hectaresperyearwithwoodashtohelpalleviatetheCadeclineproblem.AstheHollowRiver

Watershed is40,000hectares, aprovincewidewoodashrecyclingprogrammemaywell

solve the current Ca decline problem in 9 to 10 years with available ash supplies. A

permanentwoodashrecyclingprogrammecould thencontinue tosupport forestgrowth

andlakehealthinthefuture.Basedontheseestimates,a largerscalewoodashrecycling

programmeisjustified,assumingtherearenootherproblemsthattheuseofwoodashmight

14

cause.Wewilladdressthesepotentialproblems(metallevelsandaquatictoxicity)inour

nexttechnicalreport

15

7.0 REFERENCES

1. Risse,L.M.&J.W.Gaskin.(2002).Bestmanagementpracticesforwoodashasagriculturalsoil

amendment. Bulletin 1141. The University of Georgia Cooperative Extension. Available at

http://extension.uga.edu/publications/detail.html?number=B1142 (Accessed September 28,

2017)

2. Perry,E. (n.d.).Woodashesasagarden fertilizer.UniversityofCalifornia,Cooperative

Extension,DivisionofAgriculturalSciences-VegetableResearchandInformationCenter.

Leaflet 21305. Available at http://vric.ucdavis.edu/pdf/fertilization_Woodashes.pdf

(AccessedJuly7,2017)

3. Reid, C. & S. A. Watmough. (2014). Evaluating the effects of liming and wood-ash

treatmenton forestecosystems throughsystematicmeta-analysis.Canadian Journalof

ForestryResearch44:867-885.

4. Hannam,K.D.,C.Deschamps,M.Kwiaton,L.Venier,&P.W.Hazlett.(2016).Regulations

andguidelinesfortheuseofwoodashasasoilamendmentinCanadianforests.Natural

ResourcesCanada,CanadianForestryService,Ontario,Canada.

5. CanadianTire.(n.d.).BlackCoalHod.Availableathttp://www.canadiantire.ca/en/

pdp/black-coal-hod-0642749p.html#srp(AccessedOctober4,2017).

16

6. Naik,T.R.,R.N.Kraus,&R.Kumar.(2001).Woodash:anewsourceofpozzolanicmaterial.

ReportNo.CBU-2001-10.Availableathttps://www4.uwm.edu/cbu/Papers

/2001%20CBU%20Reports/CBU%202001-10.pdf(AccessedOctober4,2017).

7.NorthernHardwood.(2007).Wood-informed.

Availableathttp://www.northernhardwood.ca.informed-firewood-ontario.htm

(AccessedOctober9,2017).

8.TheDistrictMunicipalityofMuskoka.(2015-2016).Population:permanentandseasonal

populations.Availableathttps://www.muskoka.on.ca/

en/work-and-invest/Population.aspx(AccessedOctober5,2017).

9. Statistics Canada. (n.d.). Table 153-0145: Households and the environment survey,

primaryheatingsystem,Canada,provincesandcensusmetropolitanareas(CMA),every

2years(percent),CANSIM(database).Availableathttp://www5.statcan.gc.ca/cansim/

a26?lang=eng&retrLang=eng&id=1530145&pattern=&csid=(AccessedOctober9,

2017).

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APPENDIX

18

Appendix1:SurveyofwoodashusersinMuskoka

SURVEYOFWOODASHUSERSINMUSKOKA

Name:________________________________________________________________Address/Tele/Email:_______________________________________________________________________________________________________________________________________________________________________________________Pleaseindicatewithatickorticks(Ö)youranswer(s).1. Doyouusewoodorwoodproductsasaheatingsource?

� Yes � No

2. Ifyouarenotusingwood/woodproductsforheat,howareyouusingit?� Forbonfires� Foreliminationofyardorgardenwaste� Forwoodfiredcooking(e.g.,anoutdoorpizzaoven)� Topreparemaplesyrup� Other(pleasespecify)________________________________________________________________________

3. Whatis/arethemainsource(s)ofwoodyouuse?

� Biochar� Mixedwood� Hardwood� Softwood� Woodpellets� Other(pleasespecify)___________________________________________________________________________

4. Whatpartsofthetreesdoyouusuallyuse(tickallthatapply)?� Bark� Branches� Foliage� Roots� Stem/trunk� Other(pleasespecify)_______________________________________________________________________

5. Whattreespeciesprovideyourwood?� Beech� Maple� Oak� Other(pleasespecify)________________________________________________________________________

19

6. Howdoyouusetheashyouproduce?� Compost� Fertilizeronyourproperty� Pestcontrol(e.g.,deterslugsandsnails)� Melticeandsnowondriveway� Makingsoap� Aroundthehouse(e.g.,absorbodours,polishsilver)� Other(pleasespecify)________________________________________________________________________

7. Doyouproducewoodashonlyinthewinter?� Yes � No

8. Ifyoudonotproducewoodashonlyinthewinter,whenelsedoyoudoso?� Autumn� Spring� Summer

9. AreyouwillingtoparticipateinawoodashrecyclingprogrammeintheMuskoka?� Yes � No

10. Ifyes,howareyouwillingtoparticipate?� Transportwoodashtolandfill,i.e.thedump� Transportwoodashtoacentralizedlocationclosertohome� Separateashfromorganicwasteforcurbsidepickup� Participateinateamthatdistributesashintheforest� Helppromoteandparticipateinan“ashdrive”� Serveonawoodashrecyclingprogram’sadvisorycommittee� Other(pleasespecify)________________________________________________________________________

11. Howmanybucketsofashdoyouproduceduringtheheatingseason?� 1-2� 3-5� 5-10� >10

20

� Other(pleasespecify)_______________________________________________________________________

12. Howmanyfacecords(4’Hx8’Lx16”D)ofwooddoyouburnduringtheheating?� 1-2� 2-3� 3-4� >5� Other(pleasespecify)_______________________________________________________________________

THANKYOUFORYOURPARTICIPATION